KR20200057167A - Polypropylene resin composition and method for preparing the same - Google Patents

Abstract

The present invention provides a polypropylene resin composition having a reduced amount of TVOC generated and high impact strength; and a method for preparing the same.

Description

Polypropylene resin composition and manufacturing method therefor {POLYPROPYLENE RESIN COMPOSITION AND METHOD FOR PREPARING THE SAME}

The present invention relates to a polypropylene resin composition showing a high impact strength and a method for manufacturing the same.

Olefin polymerization catalyst systems can be classified into Ziegler-Natta and metallocene catalyst systems, and these two highly active catalyst systems have been developed to suit each characteristic. The Ziegler Natta catalyst has been widely applied to existing commercial processes since it was invented in the 50s, but because it is a multi-site catalyst with multiple active sites, the molecular weight distribution of the polymer is characterized by a wide range of comonomers. There is a problem that there is a limit to securing the desired physical properties because the composition distribution of the is not uniform.

On the other hand, the metallocene catalyst is composed of a combination of a main catalyst having a transition metal compound as a main component and a cocatalyst having an organometallic compound having aluminum as a main component. Such a catalyst is a homogeneous complex catalyst, and is a single site catalyst. Is, the molecular weight distribution is narrow according to the properties of a single active point, a polymer having a uniform composition distribution of the comonomer is obtained, and the stereoregularity of the polymer, copolymerization characteristics, molecular weight, It has properties that can change the crystallinity, etc.

Recently, due to changes in environmental awareness, many products are pursuing a reduction in the generation of volatile organic compounds (VOC). However, in the case of the Ziegler-Natta catalyst (Z / N) used in the production of the conventional impact polypropylene (Impact PP), there was a problem of generating high TVOC.

In addition, although a method of manufacturing Impact PP using a metallocene catalyst has been proposed to solve this problem, it exhibits a low total volatile organic compound (TVOC) compared to Z / N, but has low impact strength, making it difficult to apply realistically.

Accordingly, an object of the present invention is to provide a polypropylene resin composition exhibiting high impact strength and a method for manufacturing the same.

According to one embodiment of the invention, the homo polypropylene; And ethylene-propylene rubber, wherein the homo polypropylene has a melting temperature (Tm) of 145 ° C or less, a molecular weight distribution (MWD) of 2.7 or less, and the ethylene-propylene rubber has an ethylene content of 50 based on the total weight of the rubber. To 60% by weight, and a polypropylene resin having a melt index of 10 g / 10min or less (measured under a load of 2.16 kg at 230 ° C. according to ASTM D1238), which is included in 12 to 20% by weight based on the total weight of the polypropylene resin composition. Provides the composition:

According to another embodiment of the present invention, hydrogen is added in the presence of a catalyst composition comprising a transition metal compound represented by the following Chemical Formula 1 to polymerize the propylene monomer, the melting temperature (Tm) is 145 ° C. or less, and molecular weight distribution (MWD) producing a homo polypropylene having a 2.7 or less; And introducing a propylene monomer and an ethylene monomer to the homo polypropylene and polymerizing the mixture for a period of time greater than 30 minutes and less than 60 minutes, and the hydrogen is 50 based on the total weight of the propylene monomer used in preparing the polypropylene resin composition. Provided is a method for preparing the above-described polypropylene resin composition, which is added in an amount of ppm to less than 300 ppm:

[Formula 1]

In Chemical Formula 1,

A is carbon or silicon,

M is a group 14 element,

R ¹ is C _1-20 alkyl; Or C _6-20 aryl which is unsubstituted or substituted with C _1-20 alkyl,

R ² is C _6-20 aryl substituted with C _1-20 alkyl,

R ³ and R ⁴ are each independently C _1-20 alkyl,

X ¹ and X ² are each independently halogen.

According to another embodiment of the invention, there is provided an injection molded article manufactured using the polypropylene resin composition.

According to the present invention, the TVOC generated in the manufacturing process is small, and a polypropylene resin composition having high impact strength is provided.

The terminology used herein is only used to describe exemplary embodiments, and is not intended to limit the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, the terms "include", "have" or "have" are intended to indicate that an implemented feature, step, component or combination thereof exists, one or more other features or steps, It should be understood that the possibility of the presence or addition of components, or combinations thereof, is not excluded in advance.

The present invention can be variously modified and may have various forms, and specific embodiments will be illustrated and described in detail below. However, this is not intended to limit the invention to a specific disclosure form, and it should be understood that it includes all modifications, equivalents, and substitutes included in the spirit and scope of the invention.

Hereinafter, a polypropylene resin composition and a method of manufacturing the same according to specific embodiments of the present invention will be described.

The present inventors, as a result of repeated research for the production of a high-impact polypropylene resin composition, produced a novel transition metal compound having excellent C2 copolymerization due to the characteristic structure of Pseudo C2-Symmetric, which is a polymerization catalyst for polypropylene production When used as a furnace, it was confirmed that the impact strength characteristics of the polypropylene produced by controlling the hydrogen input amount can be greatly improved. Furthermore, a polypropylene resin composition exhibiting high impact strength was prepared by controlling the polymerization time during rubber polymerization together with the polypropylene to control the rubber content in the resin composition.

Thus, the polypropylene resin composition according to an embodiment of the invention,

(a) homo polypropylene having a melting temperature (Tm) of 145 ° C or less and a molecular weight distribution (MWD) of 2.7 or less; And

(b) ethylene-propylene rubber having an ethylene content of 50 to 60% by weight based on the total weight of the rubber, wherein the ethylene-propylene rubber comprises 12 to 20% by weight based on the total weight of the polypropylene resin composition,

A melt index of 10 g / 10 min or less (measured under a load of 2.16 kg at 230 ° C. according to ASTM D1238).

Hereinafter, each component will be described in detail.

(a) Homo polypropylene

Homo polypropylene in the resin composition according to one embodiment of the present invention is prepared by polymerization reaction of a propylene monomer while introducing hydrogen in the presence of a catalyst composition comprising a transition metal compound having a structure of Pseudo C2-Symmetric , As described above, the melt temperature (Tm) and the molecular weight distribution (MDW) realize the optimized physical properties, and as a result, excellent processability and strength characteristics can be exhibited.

Specifically, the homo polypropylene can exhibit excellent meltability by exhibiting a low melting temperature of 145 ° C. or less, and accordingly, it is possible to lower the processing temperature during the processing process using the homo polypropylene, thereby obtaining an energy saving effect. In addition, blending is easy. More specifically, it is 130 ° C or higher, or 140 ° C or higher, and has a melting temperature of 145 ° C or lower.

Meanwhile, in the present invention, the melting temperature may be measured using a differential scanning calorimeter (DSC). Specifically, after increasing the temperature of the homo polypropylene to 200 ° C., maintaining at that temperature for 5 minutes, and then lowering to 30 ° C., increasing the temperature again to increase the temperature of the DSC (Differential Scanning Calorimeter, manufactured by TA) curve It can be measured by setting the top of the melt temperature. At this time, the rate of temperature rise and fall is 10 ° C / min, respectively, and the melting temperature is the result measured in the section where the second temperature rises.

In addition, the homo polypropylene exhibits a narrow molecular weight distribution of 2.7 or less together with the above melting temperature. As a result, excellent stiffness and impact strength characteristics can be exhibited. More specifically, it may be 2.0 or more, or 2.5 or more or 2.6 or more, and may have a molecular weight distribution of 2.7 or less or 2.69 or less.

Furthermore, the homo polypropylene has a high weight average molecular weight (Mw) of 250,000 g / mol or more in an input condition of 50 ppm or more and less than 300 ppm of hydrogen gas through control of the amount of hydrogen gas during polymerization reaction for the production thereof. And a melting index of 7 g / 10 min or less (MI, measured by a load of 2.16 kg at 230 ° C. according to ASTM D1238). As it exhibits such a high weight average molecular weight and a low melting index, it can be controlled through control of the amount of hydrogen gas during polymerization reaction, so that a wide range of grade production is possible. More specifically, it is 260,000 g / mol or more, or 270,000 g / mol or more, and can have a weight average molecular weight of 500,000 g / mol or less, or 400,000 g / mol or less, and 5 g / 10min or more, or 6 g / 10min Or higher, and may have a melt index of 7 g / 10 min or less, or 6.9 g / 10 min or less.

Meanwhile, in the present invention, the weight average molecular weight (Mw) and molecular weight distribution (MWD) of the homo polypropylene can be measured using gel permeation chromatography (GPC), and MWD is the weight average molecular weight (Mw) and number. After measuring the average molecular weight (Mn), it can be determined by the ratio of the weight average molecular weight to the number average molecular weight (Mw / Mn). Specifically, it can be measured using a Waters PL-GPC220 instrument using a Polymer Laboratories PLgel MIX-B 300mm length column. At this time, the evaluation temperature is 160 ° C, 1,2,4-trichlorobenzene is used as a solvent, and the flow rate is 1 mL / min. In addition, samples were prepared at a concentration of 10 mg / 10 mL, and then supplied in an amount of 200 μL. The values of Mw and Mn are derived using an assay curve formed using polystyrene standards. At this time, the molecular weight (g / mol) of the polystyrene standard product was 9 species of 2,000 / 10,000 / 30,000 / 70,000 / 200,000 / 700,000 / 2,000,000 / 4,000,000 / 10,000,000.

As described above, the homo polypropylene according to an embodiment of the present invention can exhibit excellent melt processability when molding into various products such as various molded articles as it has a low melting temperature and a melt index, and a narrow molecular weight distribution and a high weight average molecular weight. In addition, it is possible to exhibit mechanical properties such as high strength.

(b) Propylene-ethylene rubber

The propylene-ethylene rubber in the resin composition according to one embodiment of the present invention serves to further increase the impact strength of the polypropylene resin composition, and this effect is increased through control of the ethylene content in the propylene-ethylene rubber Can be. Specifically, the ethylene content in the propylene-ethylene rubber may be 50 to 60% by weight. If the ethylene content is less than 50% by weight, it is difficult to obtain a sufficient strength property improvement effect, and if it exceeds 60% by weight, the compatibility with homo polypropylene decreases, and the rubber properties decrease due to the formation of propylene and ethylene into blocks, resulting in a resin composition. The strength characteristics of can be rather degraded. Accordingly, when it is within the above content range, it is possible to exhibit a better effect of improving strength characteristics. More specifically, the ethylene content in the propylene-ethylene rubber is 52% by weight or more, and may be 55% by weight or less.

In the present invention, the content of ethylene in the propylene-ethylene rubber, the resin composition containing the propylene-ethylene rubber is prepared as a film or a specimen in the form of a film, fixed in a magnetic holder of an FT-IR device, and in the IR absorption spectrum. The height (H) of the 4560-3580 cm ^-1 peak reflecting the thickness of the specimen and the area (A) of the 760-680 cm ^-1 peak showing the ethylene component were measured, and measured in accordance with the method of ASTM D 5576. Calibration formula obtained by plotting the value (A / H) obtained by dividing the area (A) of the 760 to 680 cm ^-1 peak of the standard sample by the peak height (H) of 4560 to 3580 cm ^-1. The ethylene content is calculated by substituting in. Ethylene content in the rubber may be obtained by substituting the rubber content secured in the ethylene content in the resin composition calculated in Equation 1 below.

[Equation 1]

Ethylene content (% by weight) in propylene-ethylene rubber = (ethylene (C2) content in polypropylene resin composition / rubber content in polypropylene resin composition) X 100

On the other hand, the resin composition according to an embodiment of the present invention, after the production of the homo polypropylene, and then continuously propylene monomer and ethylene monomer is reacted to prepare a propylene-ethylene rubber. Accordingly, compared to the conventional polypropylene resin composition prepared by mixing propylene-ethylene copolymer with polypropylene, high impact strength can be maintained by including propylene-ethylene rubber.

In addition, it is possible to control the content of ethylene-propylene rubber in the resin composition by controlling the polymerization time (or residence time) during polymerization of the propylene-ethylene rubber, improving the impact strength and reducing the amount of TVOC caused by the inclusion of propylene-ethylene rubber In order to sufficiently express the effect, the propylene-ethylene rubber based on the total weight of the resin composition may be included in a content range of 12 to 20% by weight. If the content of rubber is less than 12% by weight, the effect of rubber inclusion cannot be sufficiently obtained, and when it exceeds 20% by weight, the properties of homo propylene, especially the melting temperature and the weight average molecular weight, are greatly reduced, making it difficult to maintain rigidity. More specifically, the propylene-ethylene rubber is 15% by weight or more based on the total weight of the resin composition, and may be included in an amount of 20% by weight or less or 18% by weight or less.

In addition, the polypropylene resin composition according to an embodiment of the present invention, in addition to the above-mentioned homo polypropylene and propylene-ethylene rubber, additives for improving physical properties required according to the use of the resin composition, specifically synthetic rubber resin (for example For example, styrene-ethylene-butylene-styrene rubber, ethylene-butylene rubber, ethylene-octene rubber, etc.); Inorganic fillers (eg, talc, clay, calcium carbonate, mica, whisker, silica, carbon fiber, glass fiber, etc.); Nucleating agents (e.g., benzylidene sorbitol, methylbenzylidene sorbitol, ethyl benzylidene sorbitol, etc.), antioxidants (tetrakis (methylene (3,5-di-t-butyl-4-hydroxy) hydrosilylnate), Tris (2,4-di-t-butylphenol) phosphite, etc., catalyst neutralizers (calcium stearate, hydrotalcite, etc.), pigments, dispersants, weathering agents, antistatic agents, UV stabilizers, slip agents, anti-blocking agents , Or an additive such as an MI synergist (eg, bis (t-butylperoxyisopropyl) benzene)).

The content of the additive may be appropriately adjusted within a range that does not impair the object of the present invention, and specifically, may be included in an amount of 0.01 to 5% by weight based on the total weight of the polypropylene resin composition.

The polypropylene resin composition having the above-described composition, by introducing hydrogen in the presence of a catalyst composition comprising a transition metal compound represented by the following formula (1) to polymerize the propylene monomer, to produce a homo polypropylene meeting the above conditions (Step 1); And introducing a propylene monomer and an ethylene monomer to the homo polypropylene to perform a polymerization reaction for a time of more than 30 minutes and less than 60 minutes (step 2), wherein the hydrogen is a propylene monomer used in the preparation of the polypropylene resin composition. It can be produced by a manufacturing method, which is added in an amount of 50 ppm or more and less than 300 ppm based on the total weight. Accordingly, according to another embodiment of the present invention, a method for preparing the polypropylene resin composition is provided:

[Formula 1]

In Chemical Formula 1,

A is carbon or silicon,

M is a group 14 element,

R ¹ is C _1-20 alkyl; Or C _6-20 aryl which is unsubstituted or substituted with C _1-20 alkyl,

R ² is C _6-20 aryl substituted with C _1-20 alkyl,

R ³ and R ⁴ are each independently C _1-20 alkyl,

X ¹ and X ² are each independently halogen.

In the present specification, unless otherwise specified, the following terms may be defined as follows.

Halogen may be fluorine (F), chlorine (Cl), bromine (Br) or iodine (I).

The C _1-20 alkyl group may be a straight chain, branched or cyclic alkyl group. Specifically, the C _1-20 alkyl group is a C _1-15 straight chain alkyl group; C _1-10 straight chain alkyl group; C _1-5 straight chain alkyl group; C _3-20 branched or cyclic alkyl group; C _3-15 branched or cyclic alkyl group; Or a C _3-10 branched or cyclic alkyl group. More specifically, the alkyl group of C1-20 is methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, tert-butyl group, n-pentyl group, iso-pentyl group, neo -It may be a pentyl group or a cyclohexyl group.

The C _2-20 alkenyl group may be a straight chain, branched or cyclic alkenyl group. Specifically, the C _2-20 alkenyl group is a C _2-20 straight chain alkenyl group, a C _2-10 straight chain alkenyl group, a C _2-5 straight chain alkenyl group, a C _3-20 branched alkenyl group, and a C _3-15 branched alkenyl group. It may be a nil group, a C _3-10 branched alkenyl group, a C _5-20 cyclic alkenyl group or a C _5-10 cyclic alkenyl group. More specifically, it may be a C _{2- 20} alkenyl group is ethenyl group, propenyl group, butenyl group, pentenyl group or cyclohexenyl group.

C _6-30 aryl can mean a monocyclic, bicyclic or tricyclic aromatic hydrocarbon. Specifically, C _6-30 aryl may be a phenyl group, a naphthyl group or anthracenyl group.

C _7-30 alkylaryl may mean a substituent in which one or more hydrogens of aryl are substituted by alkyl. Specifically, C _7-30 alkylaryl may be methylphenyl, ethylphenyl, n-propylphenyl, iso-propylphenyl, n-butylphenyl, iso-butylphenyl, tert-butylphenyl or cyclohexylphenyl.

C _7-30 arylalkyl may mean a substituent in which one or more hydrogens of alkyl are substituted by aryl. Specifically, C _7-30 arylalkyl may be a benzyl group, phenylpropyl or phenylhexyl.

Specifically, in the manufacturing method according to an embodiment of the present invention, step 1 is a step of manufacturing a homo polypropylene having a melting temperature (Tm) of 145 ° C or less and a molecular weight distribution (MWD) of 2.7 or less, as described above.

Homo polypropylene that implements the above properties, after pre-polymerization for a propylene monomer in the presence of a catalyst composition comprising a transition metal compound represented by the formula (1), through the polymerization process of polymerizing the propylene monomer by introducing hydrogen Can be manufactured.

The catalyst composition for the production of the homo polypropylene includes the transition metal compound of Formula 1, wherein the transition metal compound of Formula 1 has a structure of C2-Symmetric for maintaining isotacticity in the polymerization of polypropylene. It has a structure of Pseudo C2-Symmetric that can implement each characteristic of both indens. Accordingly, since it has various characteristics of two different indens or can take selective advantages, it can exhibit better catalytic activity.

Specifically, the transition metal compound of Formula 1 is a bridge group that connects two ligands including an indenyl group, and includes a divalent functional group A substituted with alkyl groups (R ³ and R ⁴ ) having 1 or more carbon atoms, thereby having an atomic size. As it increases and the available angle increases, it is easy to access the monomers and thus can exhibit better catalytic activity.

In addition, one of the two indenyl groups, which are ligands, is substituted only at position 3 (R ¹ ), and the other indenyl group has an asymmetric structure by replacing positions 2 and 4 with methyl groups and R ² , respectively. Accordingly, it is possible to exhibit an effect of lowering the melting temperature by controlling the tacticity in the molecular structure of polypropylene.

In addition, in the case of the indenyl ligand in which only the 3 position is substituted, compared to the case where the other position is substituted, the polymer to be produced may exhibit a narrower molecular weight distribution. C _1-20 alkyl as the substituent at position 3; Or C _6-20 aryl substituted or unsubstituted with C _1-20 alkyl, and more specifically, C _3-10 linear alkyl such as n-propyl, n-butyl, and the like; C _3-10 pulverized alkyl such as isopropyl; Phenyl; Or phenyl substituted with C _3-6 branched alkyl such as t-butylphenyl. When substituted with these substituents, higher catalytic activity can be exhibited.

In addition, in the case of an indenyl ligand in which positions 2 and 4 are respectively substituted, position 2 may include methyl, and position 4 (R ² ) may include C _6-20 aryl substituted with C _1-20 alkyl. have. In this way, by replacing each position, excellent catalytic activity can be exhibited by an inductive effect capable of supplying sufficient electrons.

More specifically, R ² in Chemical Formula 1 may be a phenyl group substituted with a C _3-6 branched alkyl group such as tert-butyl phenyl. In addition, the substitution position of the alkyl group with respect to the phenyl group may be the 4th position corresponding to the R ² position and the para position bonded to the indenyl group.

In addition, the compound of Formula 1 may include a group 14 metal such as zirconium (Zr) or hafnium (Hf) as the center metal (M), and when it includes zirconium (Zr), other 14 such as Hf It has more orbitals capable of accepting electrons compared to when containing a group element, so it can be easily combined with a monomer with a higher affinity, and as a result, it can exhibit a better catalytic activity improvement effect.

In addition, in Formula 1, X ¹ and X ² may be each independently chloro.

In addition, in Formula 1, A may be silicon (Si), and the substituents R ³ and R ⁴ of A are the same as each other in terms of improving solubility and increasing loading efficiency, and may be C _1-10 alkyl. And more specifically C _1-4 straight-chain alkyl, and more specifically, each may be a methyl group. Thus, by having the same alkyl group as each other as a substituent for A of the bridge group, when preparing a supported catalyst, solubility is excellent, and thus improved supported reactivity can be exhibited.

Representative examples of the compound represented by Chemical Formula 1 include compounds having the following structure:

The compound of Formula 1 may be prepared by reacting a ligand compound of Formula 2 with a halide containing a Group 14 element:

[Formula 2]

In Formula 2, R ¹ to R ⁴ and A are as defined above.

Reaction Scheme 1 below shows a ligand compound used in the preparation of the transition metal compound according to an embodiment of the present invention, and a process for preparing the transition metal compound using the ligand compound. Scheme 1 below is only an example for illustrating the present invention, but the present invention is not limited thereto.

* Hereinafter, with reference to Reaction Scheme 1, the transition metal compound according to an embodiment of the present invention is substituted with an indene compound (I) in which position 3 is substituted with a functional group of R ¹ , such as butyl lithium (n-BuLi). Reacting with a bridge group providing compound (II) such as halogenated dimethyldichlorosilane in the presence of lithium to prepare an indene compound (III) having a bridge group attached thereto; The indene compound (III) in which the bridge group is bonded is an indene compound (IV) in which positions 2 and 4 are substituted with substituents of methyl and R ² in the presence of alkyllithium such as butyllithium (n-BuLi) and CuCN, respectively. ) To react to prepare the ligand compound (2) of Formula 2; And reacting the ligand compound (2) with a halide containing a Group 14 element such as ZrCl ₄ to prepare the transition metal compound (1) of Formula 1; .

[Scheme 1]

In Reaction Scheme 1, A, M, R ¹ to R ⁴ , X ¹ and X ² are as defined above, and X is a halogen group.

The reaction in each step can be carried out by applying known reactions, and a more detailed synthesis method can refer to a preparation example described later.

The above-described transition metal compound may generate stereoregular polypropylene due to a pseudo C2-Symmetric structure, and may exhibit characteristics of narrowing a molecular weight distribution. As a result, when used as a catalyst for the production of polypropylene, TVOC generation is reduced, and the impact strength of the produced polypropylene can be increased.

In addition, the catalyst composition for the production of the homo polypropylene contains the transition metal compound of Formula 1 as a single catalyst. Accordingly, the molecular weight distribution may be significantly narrower than that of the homo polypropylene produced compared to the case where two or more types of catalysts are mixed and used, and as a result, excellent strength characteristics may be exhibited.

In addition, the transition metal compound of Formula 1 may be used as a single component or may be used as a supported catalyst supported on a carrier. When used as a supported catalyst, the morphology and physical properties of the polypropylene to be produced are excellent, and can be suitably used in a conventional slurry polymerization, bulk polymerization, or gas phase polymerization process.

Specifically, as the carrier, a carrier having a hydroxy group, a silanol group, or a siloxane group having high reactivity on the surface may be used, and for this purpose, the surface is modified by calcination or moisture is removed from the surface by drying. Can be used. For example, silica prepared by calcining silica gel, silica dried at high temperature, silica-alumina, and silica-magnesia may be used, and these are usually Na ₂ O, K ₂ CO ₃ , BaSO ₄ , and Mg (NO ₃ ) Oxides such as ₂ , carbonates, sulfates, and nitrate components.

When calcining or drying the carrier, the temperature may be 200 to 600 ° C, and may be 250 to 600 ° C. When the calcination or drying temperature for the carrier is lower than 200 ° C, there is a possibility that the moisture remaining on the carrier is too large to react with the surface moisture and the co-catalyst, and the co-catalyst is retained due to the hydroxyl groups present in excess. Although the percentage can be relatively high, this requires a large amount of co-catalyst. In addition, when the drying or calcination temperature exceeds 600 ° C., the surface area decreases as the pores on the surface of the carrier are combined, the surface of the carrier decreases, and there are many hydroxy groups or silanol groups on the surface, leaving only siloxane groups. May decrease.

In one example, the amount of hydroxy groups on the surface of the carrier may be 0.1 to 10 mmol / g or 0.5 to 5 mmol / g. The amount of hydroxy groups on the surface of the carrier can be controlled by the method and conditions of the carrier or drying conditions, such as temperature, time, vacuum or spray drying. If the amount of the hydroxy group is too low, there are few reaction sites with the co-catalyst, and if it is too large, it may be due to moisture other than the hydroxy group present on the surface of the carrier particle.

Among the above-mentioned carriers, in the case of silica prepared by calcining silica, especially silica gel, since the functional group of the silica carrier and the compound of Chemical Formula 1 is chemically supported, the catalyst liberated from the carrier surface in the propylene polymerization process is almost As a result, when producing polypropylene by slurry or gas phase polymerization, fouling between the walls of the reactor or polymer particles can be minimized.

In addition, when supported on a carrier, the compound of Formula 1 may be supported in a content range of 5 μmol or more, or 7 μmol or more, 100 μmol or less, or 80 μmol or less based on 1 g of silica, for example, by weight of the carrier. have. When supported in the above content range, it shows an appropriate supported catalytic activity, which can be advantageous in terms of maintaining the activity and economical efficiency of the catalyst.

In addition, the catalyst composition may further include a cocatalyst in addition to the compound of Formula 1 and a carrier, in terms of improving high activity and process stability. The cocatalyst may include one or more of the compounds represented by the following Chemical Formula 3, Chemical Formula 4 or Chemical Formula 5.

[Formula 3]

-[Al (R ₁₁ ) -O] _m-

In Chemical Formula 3,

R ₁₁ may be the same or different from each other, and each independently halogen; C _1-20 hydrocarbons; Or a C _1-20 hydrocarbon substituted with halogen;

m is an integer of 2 or more;

[Formula 4]

J (R ₁₂ ) ₃

In Chemical Formula 4,

R ₁₂ may be the same as or different from each other, and each independently halogen; C _1-20 hydrocarbons; Or a C _1-20 hydrocarbon substituted with halogen;

J is aluminum or boron;

[Formula 5]

_{^{[EH] + [ZQ 4]}} - or _{^{[E] + [ZQ 4]}} -

In Chemical Formula 5,

E is a neutral or cationic Lewis base;

H is a hydrogen atom;

Z is a group 13 element;

Q may be the same or different from each other, and each independently one or more hydrogen atoms are substituted or unsubstituted with halogen, C _1-20 hydrocarbon, alkoxy or phenoxy, C _6-20 aryl group or C _1-20 It is an alkyl group.

Examples of the compound represented by Chemical Formula 3 include aluminoxane-based compounds such as methylaluminoxane, ethylaluminoxane, isobutylaluminoxane, or butylaluminoxane, and any one or a mixture of two or more thereof can be used. .

Examples of the compound represented by Chemical Formula 4 include trimethyl aluminum, triethyl aluminum, triisobutyl aluminum, tripropyl aluminum, tributyl aluminum, dimethylchloro aluminum, triisopropyl aluminum, tri-s-butyl aluminum, and tricyclopentyl aluminum. , Tripentyl aluminum, triisopentyl aluminum, trihexyl aluminum, trioctyl aluminum, ethyl dimethyl aluminum, methyl diethyl aluminum, triphenyl aluminum, tri-p-tolyl aluminum, dimethyl aluminum methoxide, dimethyl aluminum ethoxide, trimethyl Boron, triethylboron, triisobutylboron, tripropylboron, tributylboron, and the like, and more specifically, may be one selected from trimethylaluminum, triethylaluminum, and triisobutylaluminum.

In addition, examples of the compound represented by Chemical Formula 5 include triethylammoniumtetraphenylboron, tributylammoniumtetraphenylboron, trimethylammoniumtetraphenylboron, tripropylammoniumtetraphenylboron, and trimethylammoniumtetra (p- Tolyl) boron, trimethylammoniumtetra (o, p-dimethylphenyl) boron, tributylammoniumtetra (p-trifluoromethylphenyl) boron, trimethylammoniumtetra (p-trifluoromethylphenyl) boron, tributylammonium Umtetrapentafluorophenylboron, N, N-diethylanilinium tetraphenylboron, N, N-diethylanilinium tetrapentafluorophenylboron, diethylammonium tetrapentafluorophenylboron, triphenyl Phosphoniumtetraphenylboron, trimethylphosphoniumtetraphenylboron, triethylammoniumtetraphenylaluminum, tributylammoniumtetraphenylaluminum, trimethylammoniumtetraphenylaluminum, tripropylammoniumtetraphenylaluminum, trimethylammoniumtetra (p -Tolyl) aluminum, tripropylammoniumtetra (p-tolyl) aluminum, triethylammoniumtetra (o, p-dimethylphenyl) aluminum, tributylammoniumtetra (p-trifluoromethylphenyl) aluminum, trimethylammonium Tetra (p-trifluoromethylphenyl) aluminum, tributylammoniumtetrapentafluorophenylaluminum, N, N-diethylaniliniumtetraphenylaluminum, N, N-diethylanilinium tetrapentafluorophenylaluminum , Diethylammoniumtetrapentatetraphenylaluminum, triphenylphosphoniumtetraphenylaluminum, trimethylphosphoniumtetraphenylaluminum, tripropylammoniumtetra (p-tolyl) boron, triethylammoniumtetra (o, p-dimethylphenyl ) Boron, tributylammoniumtetra (p-trifluoromethylphenyl) boron, triphenylcarboniumtetra (p-trifluoromethylphenyl) boron, or triphenylcarboniumtetrapentafluorophenylboron. And any one or a mixture of two or more of them can be used.

Considering that among the above-described cocatalysts, it is possible to exhibit better catalytic activity when used with the compound of Formula 1, the cocatalyst is a compound of Formula 3, more specifically, alkyl aluminoxane such as methylaluminoxane. Can be. The alkylaluminoxane-based cocatalyst acts as a scavenger of hydroxyl groups present on the surface of the carrier to improve activity, and converts the halogen group of the catalyst precursor to a methyl group to promote the growth of the polypropylene chain.

The co-catalyst is, for example, 8 mmol or more, or 10 mmol or more, based on 1 g of silica, and may be supported in an amount of 25 mmol or less, or 20 mmol or less. When included in the above-mentioned content range, it is possible to sufficiently obtain the effect of reducing the generation of fine powder together with the effect of improving the catalyst activity according to the use of the cocatalyst.

In addition, the catalyst composition in the form of a supported catalyst may further include an antistatic agent. As such an antistatic agent, for example, an ethoxylated alkylamine represented by the following Chemical Formula 6 may be used, and in addition, any component known as an antistatic agent may be used without limitation. By using such an antistatic agent, generation of static electricity is suppressed during polymerization / production of homo polypropylene, so that homo polypropylene with superior physical properties including the above-described physical properties can be manufactured.

[Formula 6]

R ⁷ N- (CH ₂ CH ₂ OH) ₂

In Chemical Formula 6, R ⁷ may be C _8-30 alkyl, and when R ⁷ includes an alkyl group having a carbon number in the above range, it may exhibit a fine powder reducing effect through excellent antistatic action without causing unpleasant odor. .

More specifically, the ethoxylated alkylamine may be a compound in which R ⁷ in C 6 is C _8-22 straight alkyl, or C _12-18 straight alkyl, or C _13-15 straight alkyl. And one or a mixture of two or more of these compounds can be used. In addition, commercially available Atmer 163 ™ (manufactured by CRODA) may be used.

In addition, when an antistatic agent is further included, it may be included in 1 to 10 g, more specifically 1 to 5 g, based on 100 g of the carrier.

When the catalyst composition includes all of the above-described carrier, cocatalyst, and antistatic agent, the catalyst composition is supported on the carrier by supporting a cocatalyst compound, and supporting the compound represented by Formula 1 on the carrier; And it may be prepared by a manufacturing method comprising the step of injecting an antistatic agent in a slurry state and heat-treating the carrier in which the cocatalyst and the transition metal compound of Formula 1 are supported. The supported catalyst having a structure determined according to the supporting / processing order can realize excellent process stability together with high catalytic activity in the production process of polypropylene.

The catalyst composition, depending on the polymerization method, may be used as a slurry in a solvent, or may be used in a diluted state, or may be used in the form of a mud catalyst mixed with a mixture of oil and grease.

When used in a slurry or in a diluted state in a solvent, the solvent is an aliphatic hydrocarbon solvent having 5 to 12 carbon atoms suitable for the polymerization process of propylene monomers, such as pentane, hexane, heptane, nonane, decane, and these And isomers of aromatic hydrocarbon solvents such as toluene and benzene, or hydrocarbon solvents substituted with chlorine atoms such as dichloromethane and chlorobenzene, and any one or a mixture of two or more thereof may be used. In this case, the catalyst composition may further include the above-described solvent, and a small amount of water or air, which may act as a catalyst poison, may be removed by treating a small amount of alkyl aluminum with respect to the solvent before use.

In addition, when a polymerization method such as continuous bulk polymerization is used, the catalyst composition may be used in the form of a mud catalyst mixed with a mixture of oil and grease. In this case, the amount of the volatile organic compound contained in the homo polypropylene to be produced can be further reduced compared to the case where it is dissolved or diluted in a solvent, and as a result, the odor resulting from the volatile organic compound is also reduced. I can do it.

The catalyst composition having the above-described configuration includes the transition metal compound of Chemical Formula 1, thereby reducing the total amount of volatile organic compounds (TVOC) generated during the production of homo polypropylene and increasing the impact strength.

On the other hand, the polymerization process for the production of homo polypropylene can be carried out by injecting hydrogen in the presence of the catalyst composition and polymerizing the propylene monomer, wherein hydrogen is 50 ppm or more relative to the total weight of propylene used in the preparation of the resin composition. It is injected in an amount of less than 300 ppm.

More specifically, the polymerization reaction may be carried out through a process of prepolymerization by first contacting a propylene monomer with a catalyst composition comprising the compound represented by Chemical Formula 1, and then introducing a propylene monomer together with hydrogen gas. At this time, the pre-polymerization and the main polymerization process are performed as a continuous process.

The pre-polymerization may be performed for 10% or less, specifically 5 to 10% of the total polymerization process time for the production of homo polypropylene. When carried out in such a range, it is possible to produce homo polypropylene with better polymerization efficiency.

In addition, the hydrogen gas in the present polymerization process, the total weight of propylene monomers for the production of homo polypropylene, that is, the total amount of propylene monomers in the system including the propylene monomers injected during pre-polymerization can be added in an amount of 50ppm or more and less than 300ppm have. By introducing hydrogen gas into the above-described range, the molecular weight distribution and fluidity of the homo polypropylene composition produced while exhibiting sufficient catalytic activity can be adjusted within a desired range, thereby producing a homo propylene polymer having appropriate physical properties according to the application. Can be. If the hydrogen input amount is less than 50ppm or 300ppm or more, it is difficult to realize the properties of the above-mentioned homo polypropylene and resin composition, and in particular, when the hydrogen input amount is 300ppm or more, the melt index of the resin composition is greatly increased to decrease injection moldability. . More specifically, the hydrogen gas is 70 ppm or more, or 100 ppm or more, and may be introduced in a content of 250 ppm or less, or 200 ppm or less.

The polymerization process including the preliminary polymerization and the main polymerization may be performed by a continuous polymerization process, for example, a continuous solution polymerization process, a bulk polymerization process, a suspension polymerization process, a slurry polymerization process, or an emulsion polymerization process. Various polymerization processes known as polymerization reactions can be employed. In particular, a continuous bulk-slurry polymerization process may be preferable in terms of obtaining a uniform molecular weight distribution and commercial production of the product.

In addition, the polymerization process including the preliminary polymerization and the main polymerization is 40 ° C or higher, or 60 ° C or higher, and may be performed at a temperature of 110 ° C or lower or 100 ° C or lower, and further control pressure conditions, 1 kgf / cm ² or more, or 30 kgf / cm ² or more, and 100 kgf / cm ² It may be performed under a pressure of 50 kgf / cm ² or less.

Further, during the polymerization reaction, trialkyl aluminum such as triethyl aluminum may be selectively further added.

When moisture or impurities are present in the polymerization reactor, a part of the catalyst is decomposed. Since the above-described trialkyl aluminum serves as a scavenger that pre-captures moisture or impurities contained in the reactor or moisture contained in monomers, The activity of the catalyst used for production can be maximized, and as a result, homo polypropylene having excellent physical properties, particularly a narrow molecular weight distribution, can be more efficiently produced. Specifically, in the trialkyl aluminum, alkyl is as defined above, specifically C _1-20 alkyl, and more specifically C _1-6 linear or branched alkyl alkyl such as methyl, ethyl, isobutyl, and the like. Can be.

In addition, the trialkyl aluminum (based on 1M) may be added in an amount of 300 ppm or more, or 400 ppm or more, 600 ppm or less, or 450 ppm or less based on the total weight of the propylene monomer, and the presence of trialkyl aluminum in this content range Under the polymerization reaction, homo polypropylene production of desired physical properties may be easier.

Homo polypropylene according to an embodiment of the invention prepared by the above-described manufacturing method, by having the optimum combination properties as described above can improve the impact strength of the resin composition.

Next, the manufacturing method according to an embodiment of the present invention includes the steps of preparing propylene-ethylene rubber in the resin composition by continuously polymerizing and reacting propylene and ethylene with respect to the homo polypropylene prepared in the above step.

The propylene and ethylene may be added at an appropriate mixing ratio in consideration of each content in the propylene-ethylene rubber to be prepared, and more specifically, may be added at a weight ratio of 1: 1 to 1: 1.2.

In addition, the reaction of the propylene and ethylene may be carried out in a gas phase polymerization method, 50 ℃ or more, or more than 70 ℃ and 60 ℃ or less temperature and 5 bar or more, or 10 bar or more and 25 bar or less, or 20 bar or less pressure It can be carried out under.

In addition, the reaction time between propylene and ethylene affects the content of propylene-ethylene rubber produced in the resin composition. Accordingly, the reaction time may be specifically 30 minutes or more and 60 minutes or less. When performed within the above range, propylene-ethylene rubber may be formed in an amount of 12 to 20% by weight based on the total weight of the resin composition. More specifically, it may be performed for 40 minutes to 60 minutes.

The polypropylene resin composition according to one embodiment of the invention manufactured according to the above-described manufacturing method shows a low melt index compared to a conventional impact resin composition, and the melt index measured by a load of 2.16 kg at 230 ° C. according to ASTM D1238. It has a low melt index of 10 g / 10 min or less, and as a result, it can exhibit more improved impact strength characteristics along with excellent workability.

Specifically, the polypropylene resin composition is 9 g / 10min or less, or 8.5 g / mol or less, and may have a melt index of 5 g / 10min or more, or 8 g / 10min or more.

In addition, the polypropylene resin composition is Izod impact strength measured in accordance with ASTM D256 method is 5 to 10 kg.f.cm/cm, or 8 to 10 kg.f.cm/cm at a normal temperature of 23 ° C, -20 It is 2 to 5 kg.f.cm/cm and 3.5 to 5 kg.f.cm/cm at a low temperature condition of ℃.

In addition, the amount of TVOC generated during the production of the polypropylene resin composition may be reduced, and in particular, the amount of generation of TVOC may be greatly reduced as compared with the impact resin composition containing homo polypropylene produced using a Ziegler-Natta catalyst. Specifically, the polypropylene resin composition has a TVOC content of 60 ppm or less, more specifically 52 ppm or less or 50 ppm or less, measured according to VDA277.

Accordingly, according to another embodiment of the present invention, a molded article manufactured using the polypropylene resin composition is provided.

The molded article may be manufactured according to a conventional method known in the art of the present invention, except for using the resin composition of one embodiment described above, and may be an injection molded article manufactured through an extrusion process and an injection process. More specifically, it may be an automotive exterior material component such as a bumper or side seal molding.

Hereinafter, preferred embodiments are presented to help understanding of the present invention. However, the following examples are only for illustrating the present invention, and the contents of the present invention are not limited by the following examples.

<Preparation of supported catalyst>

Preparation Example 1-1

Step 1: Dimethylsilanediyl (3-phenyl-1H-inden-1-yl) (2- methyl -4- (4- tert - Butylphenyl ) -1H- inden)

After dissolving 3-phenyl-1H-indene equivalent (1eq) in a mixed solution of toluene / THF (10/1 volume ratio, 0.5M), n-BuLi (1.05) at -25 ° C eq) was slowly added dropwise, followed by stirring at room temperature for 3 hours. Dichloro dimethyl silane (1.05 eq) was added to the resulting reactant at -10 ° C, followed by stirring overnight at room temperature to prepare a mono-Si solution.

To another reactor, 2-methyl-4- (4-tert-butylphenyl) indene (2-Me-4- (4-tBuPh) Indene) (1 eq) was mixed with a toluene / THF solution (5/1 volume ratio, 0.7 After dissolving in M), n-BuLi (1.05 eq) was slowly added dropwise at -25 ° C, followed by stirring at room temperature for 3 hours. CuCN (2 mol%) was added to the resulting reaction mixture, and after stirring for 30 minutes, the mono-Si solution was added thereto. Thereafter, the mixture was stirred overnight at room temperature, worked-up with water, and dried to obtain a ligand.

Step 2: Dimethylsilanediyl (3-phenyl-1H-inden-1-yl) (2- methyl -4- (4- tert - Butylphenyl ) -1H-Inden-1-yl) Preparation of zirconium dichloride

The ligand prepared above was dissolved in a mixed solution of toluene / diethyl ether (2/1 volume ratio, 0.53M) and n-BuLi (2.05eq) was added at -25 ° C and then stirred at room temperature for 5 hours. Did. For the resulting reaction, a slurry prepared by mixing ZrCl ₄ (1 eq) in toluene (0.17 M) in a separate flask was added at −25 ° C., followed by stirring overnight at room temperature.

When the reaction was completed, the solvent was vacuum dried, dichloromethane (DCM) was re-injected, LiCl was removed through a filter, the filtrate was dried in vacuo, and DCM / hexane was added to recrystallize at room temperature. The resulting solid was then filtered and dried in vacuo to give the titled transition metal compound in the solid phase.

Pseudo-rac: 7.72 (dd, 2H), 7.56 (d, 2H), 7.5-6.7 (m, 12H), 6.61 (s, 1H), 6.07 (s, 1H), 2.15 (s, 3H), 1.46 ( s, 3H), 1.3 (s, 9H), 1.07 (s, 3H) ppm

Step 3: Preparation of supported catalyst

Silica gel (SYLOPOL 952X ™, calcinated under 250 ° C, 100g) was placed in a 2L reactor under Ar, and 766 mL of 10% by weight methylaluminoxane (MAO) toluene solution (corresponding to 10 mmol per 1 g of silica) was slowly injected at room temperature. Stir at 90 ° C. for 15 hours. After completion of the reaction, the mixture was cooled to room temperature and left for 15 minutes to decant the solvent using cannula. 400 mL of toluene was added, stirred for 1 minute, left for 15 minutes, and the solvent was decant using cannula. 700 μmol of the transition metal compound prepared above was dissolved in 400 mL of toluene, and then transferred to a reactor using cannula. After stirring at 50 ° C for 5 hours, the mixture was cooled to room temperature and left for 15 minutes to decant the solvent using cannula. 400 mL of toluene was added, stirred for 1 minute, left for 15 minutes, and decant of the solvent using cannula was performed twice. In the same manner, 400 mL of hexane was added, stirred for 1 minute and left for 15 minutes to decant the solvent using cannula, and an antistatic agent (Atmer 163 ™, 3 g manufactured by CRODA) was dissolved in 400 mL of hexane and transferred using cannula to the reactor. Did. After stirring at room temperature for 20 minutes, the solvent was removed by transfer to a glass filter. The mixture was first dried under vacuum at room temperature for 5 hours, and second dried under vacuum at 45 ° C. for 4 hours to obtain a supported catalyst.

Preparation Example 1-2

Steps 1 and 2: Preparation of transition metal compounds

In step 1 of Preparation Example 1-1, except for using 3-n-butyl-1H-indene instead of 3-phenyl-1H-indene, it was carried out in the same manner as in Steps 1 and 2, Dimethylsilanediyl (3-n-butyl-1H-inden-1-yl) (2-methyl-4- (4-tert-butylphenyl) -1H-inden-1-yl) zirconium dichloride was prepared.

Pseudo-rac: 7.57 (d, 1H), 7.4-6.8 (m, 10H), 6.61 (s, 1H), 5.67 (s, 1H), 2.86 (t, 2H), 2.16 (s, 3H), 1.58 ( m, 2H), 1.42 (s, 3H), 1.33 (s, 9H), 1.4-1.2 (m, 2H), 1.03 (s, 3H), 0.92 (t, 3H) ppm

Step 2: Preparation of supported catalyst

A supported catalyst was prepared in the same manner as in Step 3 of Preparation Example 1-1, except that the compound of the following structure was used as the transition metal compound in Step 3 of Preparation Example 1-1.

Preparation Example 1-3

Steps 1 and 2: Preparation of transition metal compounds

Dimethyl of the above structure was carried out in the same manner as in steps 1 and 2, except that 3-isopropyl-1H-indene was used instead of 3-phenyl-1H-indene in step 1 of Preparation Example 1-1. Silanediyl (3-isopropyl-1H-inden-1-yl) (2-methyl-4- (4-tert-butylphenyl) -1H-inden-1-yl) zirconium dichloride was prepared.

Pseudo-rac: 8.29 (d, 1H), 7.49-7.30 (m, 9H), 7.16 (d, 1H), 6.36 (s, 1H), 6.17 (s, 1H), 2.38 (q, 2H), 2.08 ( s, 3H), 1.33 (s, 9H), 0.86 (d, 6H), 0.72 (s, 6H) ppm

Step 3: Preparation of supported catalyst

A supported catalyst was prepared in the same manner as in Step 3 of Preparation Example 1-1, except that the compound of the following structure was used as the transition metal compound in Step 3 of Preparation Example 1-1.

Comparative Production Example 1-1

Ziegler Natta catalyst (ZN127VS ™, manufactured by Lyondellbasell) was used.

Comparative Production Examples 1-2 to 1-5

A supported catalyst was prepared in the same manner as in Step 3 of Preparation Example 1, except that the transition metal compound having the structure shown in Table 1 was used.

Comparative Production Example 1-2 Comparative Production Example 1-3 Comparative Production Example 1-4 Comparative Production Example 1-5

Test Example 1: Evaluation of physical properties of homo polypropylene The homo polypropylene was prepared by using the catalysts prepared in Production Examples 1-1 to 1-3, and Comparative Production Examples 1-1 to 1-5, and in the following manner. Physical property evaluation was performed. The results are shown in Table 2 below.

Preparation of homo polypropylene

The 2 L stainless reactor was dried under vacuum at 65 ° C., cooled, 3 mmol of triethyl aluminum was added at room temperature, 100 ppm of hydrogen gas was added, and 770 g of propylene (C3) was added. After stirring for 5 minutes, 30 mg of the metallocene supported catalysts prepared in Preparation Examples 1-1 to 1-3, and Comparative Preparation Examples 1-1 to 1-5 were introduced into the reactor under nitrogen pressure. After the temperature of the reactor was gradually raised to 70 ° C., a polymerization process was performed for 1 hour (polymerization conditions: 70 ° C., 1 h, C 3 = 770 g, bulk polymerization). After the reaction was completed, unreacted propylene was vented.

Melt temperature of homo polypropylene (Tm, ℃)

The temperature of the homo polypropylene was increased to 200 ° C., maintained at that temperature for 5 minutes, and then lowered to 30 ° C., and the temperature was increased again to melt the top of the DSC (Differential Scanning Calorimeter, manufactured by TA) curve. Was made. At this time, the rate of temperature rise and fall was 10 ° C / min, and the melting temperature was used as the result measured in the second temperature rise section.

Melt Index (MI, g / 10min)

Measured under a load of 2.16 kg at 230 ° C according to ASTM D1238, and expressed as the weight (g) of the polymer melted for 10 minutes.

Weight average molecular weight (Mw, g / mol) and molecular weight distribution (MWD, polydispersity index)

After measuring the weight average molecular weight (Mw) and the number average molecular weight (Mn) using gel permeation chromatography (GPC), molecular weight distribution was calculated by the ratio of Mw / Mn. Specifically, it was measured using a Waters PL-GPC220 instrument using a Polymer Laboratories PLgel MIX-B 300 mm length column. At this time, the evaluation temperature was 160 ° C, 1,2,4-trichlorobenzene was used as a solvent, and the flow rate was 1 mL / min. Samples were prepared at a concentration of 10 mg / 10 mL, and then supplied in an amount of 200 μL. The values of Mw and Mn were derived using an assay curve formed using polystyrene standards. As for the molecular weight (g / mol) of the polystyrene standard, 9 species of 2,000 / 10,000 / 30,000 / 70,000 / 200,000 / 700,000 / 2,000,000 / 4,000,000 / 10,000,000 were used.

Catalyst type Homo polypropylene property evaluation Melt temperature
(℃) Melt Index (MI)
(g / 10min) Mw
(g / mol) MWD Comparative Production Example 1-1 160 - - - Comparative Production Example 1-2 152 1.7 449,000 2.87 Comparative Production Example 1-3 155 15.7 248,000 2.40 Comparative Production Example 1-4 152 3.8 411,000 2.81 Comparative Production Example 1-5 148 9.1 261,000 5.04 Preparation Example 1-1 145 6.5 354,000 2.60 Preparation Example 1-2 144 6.2 375,000 2.69 Preparation Example 1-3 143 6.9 270,000 2.66

As a result of the experiment, the homo polypropylene produced using the catalysts of Preparation Examples 1-1 to 1-3 was lower than that of the homo polypropylene produced using the catalysts of Comparative Production Examples 1-1 to 1-5. The melting temperature and narrow molecular weight distribution were shown.

Test Example 2: C2 copolymerization evaluation of the catalyst

In order to evaluate C2 copolymerizability of the catalysts prepared in Preparation Examples 1-1 to 1-3, and Comparative Preparation Examples 1-1 to 1-5, random polypropylene was prepared (C2 copolymer), and the C2 content in the copolymer And C2 copolymerization of the catalyst by measuring the weight average molecular weight. Table 3 shows the results.

Preparation of propylene-ethylene copolymer

The 2 L stainless reactor was vacuum-dried at 65 ° C., cooled, 3 mmol of triethyl aluminum was added at room temperature, 331 ppm of hydrogen gas was added, and then 770 g of propylene was added. After stirring for 5 minutes, 30 mg of the metallocene-supported catalyst prepared in the above Production Examples and Comparative Examples was introduced into the reactor under nitrogen pressure. Thereafter, ethylene (C2) was added at 400 cc per minute (4% input level) using a mass flow controller (MFC), the reactor temperature was gradually raised to 70 ° C., and a polymerization process was performed for 1 hour. After the reaction was completed, unreacted propylene was vented.

C2 content

After making a film or film-type specimen with random polypropylene, fix it to the magnetic holder of the FT-IR equipment, and the height (H) and ethylene component of 4560 ~ 3580 cm ^-1 peak reflecting the specimen thickness in the IR absorption spectrum appear. The area (A) of the 760 to 680 cm ^-1 peak was measured, and according to the method of ASTM D 5576, the measured value was the area (A) of the 760 to 680 cm ^-1 peak of the Standard sample, 4560 to 3580. Ethylene content was calculated by plotting the value (A / H) divided by the cm ^-1 peak height (H) and substituting it for the obtained calibration formula.

Weight average molecular weight (Mw, g / mol)

The weight average molecular weight (Mw) was measured using gel permeation chromatography (GPC). Specifically, it was measured using a Waters PL-GPC220 instrument using a Polymer Laboratories PLgel MIX-B 300 mm length column. At this time, the evaluation temperature was 160 ° C, 1,2,4-trichlorobenzene was used as a solvent, and the flow rate was 1 mL / min. Samples were prepared at a concentration of 10 mg / 10 mL, and then supplied in an amount of 200 μL. The values of Mw and Mn were derived using an assay curve formed using polystyrene standards. As for the molecular weight (g / mol) of the polystyrene standard, 9 species of 2,000 / 10,000 / 30,000 / 70,000 / 200,000 / 700,000 / 2,000,000 / 4,000,000 / 10,000,000 were used.

Catalyst type In random polypropylene
C2 content
(weight%) Random Polypropylene Mw
(g / mol) Comparative Production Example 1-1 - - Comparative Production Example 1-2 1.85 264,000 Comparative Production Example 1-3 1.66 245,000 Comparative Production Example 1-4 1.76 268,000 Comparative Production Example 1-5 2.3 60,000 Preparation Example 1-1 2.57 310,000 Preparation Example 1-2 2.56 308,000 Preparation Example 1-3 2.52 288,000

As a result of the experiment, from the evaluation results of the random propylene produced using the catalysts of Preparation Examples 1-1 to 1-3, the catalysts of Preparation Examples 1-1 to 1-3 are compared to Preparation Examples 1-1 to 1-5 Compared to the homo polypropylene produced using the catalyst at, it can be seen that it shows better C2 copolymerizability. These results show that the transition metal compounds of Preparation Examples 1 to 3 containing a ligand of 3-substitute Indene Since there is a 3-position steric of silver, the position selectivity of the main chain increases during chain transfer, and accordingly, C2 of a size smaller than the existing C3 is easily accessible to the insertion site on the opposite side. In the case of a transition metal compound in which nothing is conventionally present in the 3-position, the position selectivity of the main chain is deteriorated, and thus the insertion of C2 or C3 by the steric is not affected, thereby degrading C2 copolymerization.

<Preparation of polypropylene resin composition>

Examples 1 to 5, and Comparative Examples 1 to 5

A polypropylene resin composition was prepared using a continuous pilot plant.

The metallocene supported catalyst or the Ziegler-Natta catalyst prepared in the above Preparation Examples and Comparative Preparation Examples were mixed with oil and grease, respectively, to prepare a 17% by weight catalyst mixture.

The prepared catalyst mixture solution was introduced into a pre-polymerization reactor, 20 kg / hr of propylene pretreated with a TEAL stock solution in a weight ratio of 50 ppm (retention time 8 minutes), and looped continuously with 100 ppm hydrogen. It was put into a reactor. At this time, hydrogen was introduced together with propylene flowing into the loop reactor, and the reactor temperature was maintained at 70 ° C to prepare homo polypropylene (HOMO PP) (retention time 2 hours).

After transferring the resulting powder to a gas phase reactor (GPR), propylene and ethylene were added together in a volume ratio of 1: 1, and maintained at 70 ° C. and 14 bar for 1 hour to obtain a polypropylene resin composition. .

Examples 2 to 3 and Comparative Examples 1 to 5

Polypropylene resin composition was performed in the same manner as in Example 1, except that the catalysts prepared in Preparation Examples 1-2 and 1-3, or Comparative Preparation Examples 1-1 to 1-5 were used, respectively. It was prepared.

Comparative Example 6

When the polymerization of the polypropylene resin composition in Example 1 when homo polypropylene polymerization was performed in a loop reactor, a polypropylene resin composition was performed in the same manner as in Example 1, except that the hydrogen input amount was increased to 300 ppm. Was prepared.

Comparative Example 7

When the rubber polymerization in the gas phase reactor (GPR) proceeds during polymerization of the polypropylene resin composition in Example 1, it is carried out in the same manner as in Example 1, except that the residence time is reduced to 30 minutes. A polypropylene resin composition was prepared.

Test Example 3: Evaluation of physical properties of the polypropylene resin composition

The properties of the polypropylene resin compositions prepared in Examples and Comparative Examples were evaluated in the following manner, and the results are shown in Table 4 below.

Melt temperature (Tm) and molecular weight distribution (MWD) of homo polypropylene (HOMO PP)

In the same manner as in Test Example 1, the melting temperature and molecular weight distribution of the homo polypropylene contained in the polypropylene resin composition were measured.

Melt Index (MI, g / 10min)

Measured under a load of 2.16 kg at 230 ° C according to ASTM D1238, and expressed as the weight (g) of the polymer melted for 10 minutes.

Rubber content

250 g of xylene was added to a 2 g polypropylene resin composition and refluxed for 20 minutes. Thereafter, the mixture was cooled to room temperature, and vacuum filtered to collect the filtrate and dried under vacuum. The collected polymer was dried in a vacuum oven at 80 ° C. and the mass was measured to confirm the content of xylene solubles (X.S.) in the polypropylene resin composition, and this was used as the rubber content occupying the low molecular region.

C2 content in rubber

The polypropylene resin composition was melted with a hot press machine to apply an appropriate pressure to prepare a film specimen having a thickness of 100 to 500 μm. At this time, 500 ppm of antioxidant was prescribed for the powder sample, and not prescribed for the pellet. After installing the sample holder for the magnetic holder in the sample chamber of the FT-IR instrument (Bio-Rad FTS 300), the program was executed, and the background spectrum was measured with an empty sample holder. Thereafter, the film specimen was cut to a suitable size, fixed with a magnetic holder, and placed in a chamber to measure the spectrum (FT-IR absorption spectrum). The ratio (A / H) of the maximum height (H) of the 4560 to 3580 cm ^-1 region and the width (A-integral value) of the 760 to 680 cm ^-1 region was calculated. Make a calibration formula by measuring the above spectrum with a standard sample (C2 content% vs A / H). The C2 content was obtained by substituting the spectral results (A / H) of the polypropylene resin composition film specimen into the calibration curve obtained through the standard sample. The C2 content in the rubber was obtained by substituting the previously obtained rubber content into the C2 content in the obtained polypropylene resin composition.

[Equation 1]

Ethylene content (weight%) in propylene-ethylene rubber = (ethylene (C2) content in polypropylene resin composition / rubber content in polypropylene resin composition) X 100

Eye illuminance impact strength (kg.f.cm/cm)

After preparing a film of a polypropylene resin composition according to the method of ASTM D256, the impact strength of the irradiance at room temperature (23 ° C) and low temperature (-20 ° C) was measured.

TVOC content (ppm)

The amount of total volatile organic compounds (TVOC) generated during the production of the polypropylene resin composition was measured according to the VDA277 method.

Manufacturing conditions HOMO PP evaluation Resin composition evaluation catalyst Residence time during rubber polymerization
(minute) Hydrogen input
(ppm) Tm
(℃) MWD MI (g / 10min) Rubber content
(XS weight%) C2 content in rubber
(weight%) Izod
(23 ℃)
(kg.f.cm/cm) Izod
(-20 ℃)
(kg.f.cm/cm) TVOC (ppm) Comparative Example 1 Comparative Production Example 1-1 60 100 160 7.80 7.5 16.5 38.5 10.2 4.2 310 Comparative Example 2 Comparative Production Example 1-2 60 100 153 2.87 10.0 15.5 45.1 6.5 2.1 53 Comparative Example 3 Comparative Production Example 1-3 60 100 155 2.39 8.9 16.8 39.5 6.6 2.2 51 Comparative Example 4 Comparative Production Example 1-4 60 100 152 2.81 9.5 16.5 41.5 5.4 2.0 48 Comparative Example 5 Comparative Production Example 1-5 60 100 148 5.10 28.1 15.8 49.5 6.9 2.4 61 Comparative Example 6 Preparation Example 1-1 60 300 145 2.60 40.0 15.5 53.5 7.5 3.1 48 Comparative Example 7 Preparation Example 1-1 30 100 145 2.61 8.1 10.5 53.4 6.2 2.5 50 Example 1 Preparation Example 1-1 60 100 145 2.60 8.1 15.5 53.6 8.8 3.6 50 Example 2 Preparation Example 1-2 60 100 144 2.68 8.5 16.0 51.8 8.6 3.5 51 Example 3 Preparation Example 1-3 60 100 143 2.67 8.2 15.8 52.0 8.7 3.5 49

As a result of the experiment, the resin compositions of Examples 1 to 3 prepared using the transition metal compound according to the present invention showed reduced TVOC compared to Comparative Examples, and in particular, compared with Comparative Example 1 using a conventional Ziegler-Natta catalyst. The major factors of impact strength (Izod) are the properties of homo polypropylene, the molecular weight of the rubber (higher is better), or the softness of the rubber region (i.e., the higher the C2 content in the rubber is, the better. ). The resin composition of the example prepared using the transition metal compound according to the present invention exhibited a low melt index of 10 g / 10 min or less, and a comparative example comprising homo polypropylene prepared using a metallocene-based catalyst having a different structure Compared to 2 to 5, it showed better impact strength improvement effect at room temperature and low temperature. On the other hand, in the case of Comparative Example 5, by using a catalyst excellent in C2 copolymerization, C2 conversion and content are increased to the same level as in Example, but the Mw of the homo polypropylene is low, and the molecular weight decreases during copolymerization is large, and the impact strength Decreased, and the MI of the resin composition was too high, thereby further reducing the impact strength.

In addition, in the case of Comparative Example 6, MI was excessively increased due to excessive hydrogen input during the production of homo polypropylene, and in the case of Comparative Example 7, the impact strength was lower than that of the Example as the content of the rubber in the resin composition was not satisfied. Shown.

Claims (18)

Homo polypropylene; And
Contains ethylene-propylene rubber,
The homo polypropylene has a melting temperature of 145 ° C or less, a molecular weight distribution of 2.7 or less,
The ethylene-propylene rubber has an ethylene content of 50 to 60% by weight based on the total weight of the rubber, and is included in an amount of 12 to 20% by weight based on the total weight of the polypropylene resin composition. According to the polypropylene resin composition).
According to claim 1,
The homo polypropylene is a polypropylene resin composition having a melt index of 7g / 10min or less measured at a load of 2.16 kg at 230 ° C. according to ASTM D1238.
According to claim 1,
The homo polypropylene has a weight average molecular weight of 250,000 g / mol or more, polypropylene resin composition.
According to claim 1,
The homo polypropylene has a melting temperature of 130 to 145 ° C, a molecular weight distribution of 2.0 to 2.7, a weight average molecular weight of 260,000 to 500,000 g / mol, and a melt index (measured under a load of 2.16 kg at 230 ° C according to ASTM D1238). Is 5 to 7 g / 10min, a polypropylene resin composition.
According to claim 1,
The ethylene-propylene rubber is 15 to 20% by weight based on the total weight of the resin composition, polypropylene resin composition.
According to claim 1,
The polypropylene resin composition has a melt index of 5 to 9g / 10min (measured under a load of 2.16 kg at 230 ° C according to ASTM D1238), and an Izod impact strength measured according to ASTM D256 at 5 ° C to 10 kg at a temperature of 23 ° C. .f.cm / cm, 2 to 5kg.f.cm/cm at -20 ° C low temperature condition, and the total volatile organic compound content measured according to VDA277 is 60ppm or less, polypropylene resin composition.
Injecting hydrogen in the presence of a catalyst composition comprising a transition metal compound represented by the following Chemical Formula 1 to polymerize the propylene monomer to produce a homo polypropylene having a melting temperature of 145 ° C. or less and a molecular weight distribution of 2.7 or less; And
Including the step of injecting a propylene monomer and an ethylene monomer to the homo polypropylene and polymerization reaction for more than 30 minutes and 60 minutes or less,
The hydrogen is added in an amount of 50 ppm or more and less than 300 ppm, based on the total weight of the propylene monomer used in the production of the polypropylene resin composition, the method for producing the polypropylene resin composition according to claim 1:
[Formula 1]

In Chemical Formula 1,
A is carbon or silicon,
M is a group 14 element,
R ¹ is C _1-20 alkyl; Or C _6-20 aryl which is unsubstituted or substituted with C _1-20 alkyl,
R ² is C _6-20 aryl substituted with C _1-20 alkyl,
R ³ and R ⁴ are each independently C _1-20 alkyl,
X ¹ and X ² are each independently halogen.
The method of claim 7,
R ¹ is C _3-10 straight chain alkyl; C _3-10 branched alkyl; Phenyl; Or C _3-10 is a phenyl group substituted with a branched alkyl group, a method for producing a polypropylene resin composition.
The method of claim 7,
Wherein R ² is a C _3-6 branched alkyl substituted phenyl group, a method for producing a polypropylene resin composition.
The method of claim 7,
Wherein A is silicone, M is zirconium, and R ³ and R ⁴ are methyl groups, respectively.
The method of claim 7,
The transition metal compound is selected from the group consisting of compounds of the following structure, a method for producing a polypropylene resin composition.

The method of claim 7,
The catalyst composition further comprises a silica carrier, a method for producing a polypropylene resin composition.
The method of claim 7,
The catalyst composition further comprises at least one co-catalyst selected from the group consisting of compounds of formulas 3 to 5, polypropylene resin composition.
[Formula 3]
-[Al (R ₁₁ ) -O] _m-
In Chemical Formula 3,
R ₁₁ are the same as or different from each other, and each independently halogen; C _1-20 hydrocarbons; Or a C _1-20 hydrocarbon substituted with halogen;
m is an integer of 2 or more;
[Formula 4]
J (R ₁₂ ) ₃
In Chemical Formula 4,
R ₁₂ are the same as or different from each other, and each independently halogen; C _1-20 hydrocarbons; Or a C _1-20 hydrocarbon substituted with halogen;
J is aluminum or boron;
[Formula 5]
_{^{[EH] + [ZQ 4]}} - or _{^{[E] + [ZQ 4]}} -
In Chemical Formula 5,
E is a neutral or cationic Lewis base;
H is a hydrogen atom;
Z is a group 13 element;
Q is the same or different from each other, and each independently one or more hydrogen atoms are substituted or unsubstituted with halogen, C _1-20 hydrocarbon, alkoxy or phenoxy, C _6-20 aryl group or C _1-20 alkyl group. to be.
The method of claim 7,
The catalyst composition further comprises an antistatic agent, a method for producing a polypropylene resin composition.
The method of claim 7,
The step of preparing the homo polypropylene is performed by prepolymerizing a propylene monomer in the presence of a catalyst composition comprising the transition metal compound represented by Chemical Formula 1, and then polymerizing the propylene monomer with hydrogen. Method for producing propylene resin composition.
The method of claim 7,
When the propylene monomer and ethylene monomer are added to the homo polypropylene, the propylene monomer and the ethylene monomer are introduced in a weight ratio of 1: 1 to 1: 1.5, a method for producing a polypropylene resin composition.
The method of claim 7,
The polymerization reaction after the introduction of propylene monomer and ethylene monomer to the homo polypropylene is carried out at a temperature of 50 to 70 ℃ and a pressure of 5 to 25bar, polypropylene resin composition production method.
Injection molded article comprising the polypropylene resin composition according to claim 1.