KR101677791B1 - Resin blend - Google Patents

Abstract

The present invention relates to a resin mixture, a pellet, a method for producing a resin molded article using the same, and a resin molded article. An exemplary resin mixture of the present application can provide a resin molded article whose surface has improved mechanical properties and surface hardness. In addition, when the resin mixture is used, the additional surface coating step can be omitted on the surface of the resin molded article, and the above-mentioned effect can be exhibited, so that the production time and cost can be reduced and the productivity can be increased.

Description

Resin mixture {RESIN BLEND}

The present invention relates to a resin mixture, a pellet, a method for producing a resin molded article using the same, and a resin molded article.

Plastic resins are easy to process, have excellent properties such as tensile strength, elastic modulus and heat resistance, and are used for various purposes such as automobile parts, helmets, electric device parts, spinning machine parts, toys and pipes.

In particular, resins used for household appliances, automobile parts and toys should have excellent surface hardness (Patent Documents 1 to 4).
(Patent Document 1) KR10-2010-0076154 A
(Patent Document 2) KR10-2011-0029515 A
(Patent Document 3) KR10-2011-0078783 A
(Patent Document 4) KR10-2012-0015030A

The present application provides resin mixtures and pellets.

One embodiment of the present application relates to a composition comprising a first resin; And a second resin which is a reactant of an acrylic polymer having a functional group and a reactive polyolefin resin having a reactive group capable of reacting with the functional group, wherein the second resin has a difference in surface energy, melt viscosity or solubility parameter Resin mixture.

Another embodiment of the present application includes a core formed of a first resin; And a reaction product of a polyolefin resin having a reactive group capable of reacting with an acrylic polymer having a functional group and a second resin having a difference in surface energy, melt viscosity or solubility parameter from the first resin The pellet is provided.

Hereinafter, a resin mixture, a pellet, a method for producing a resin molded article using the resin mixture, and a resin molded product according to a specific embodiment will be described in detail.

As used herein, a "mixture" may be a mixture of two or more different resins. The type of the mixture is not particularly limited, but may include a case where two or more resins are mixed in one matrix, or a case where two or more kinds of pellets are mixed. The resins may each have different physical properties, for example, the physical properties may be surface energy, melt viscosity or solubility parameter.

"Melt processing" means the process of melting a resin mixture at a temperature above the melting temperature (Tm) to form a melt blend and forming the desired molded article using the melt mixture, Molding, extrusion molding, blow molding, transfer molding, film blowing, fiber spinning, car-rendering thermoforming or foam molding.

The term "resin molded product" means a product or a pellet formed from a resin mixture. The resin molded product is not particularly limited, and examples thereof include automobile parts, electronic device parts, machine parts, functional films, have.

"Layer separation" may mean that the layer formed by substantially one resin is located or arranged on a layer formed by substantially different resins. A layer formed by substantially one resin may mean that one kind of resin does not form a sea-island structure but exists continuously over one layer. This solution structure means that the phase separated resin is partially distributed in the whole resin mixture. In addition, "substantially formed" may mean that there is only one resin in one layer or that one resin is rich.

In one example, the resin mixture can be layered by melt processing. Thus, it is possible to produce a resin molded article whose surface has a specific function, for example, a high hardness function, without a separate process such as coating and plating. Therefore, the resin molded article can have improved mechanical properties and surface characteristics, and when the resin mixture is used, the production cost and time of the resin molded article can be reduced.

The layer separation of the resin mixture may be caused by a difference in physical properties between the first resin and the second resin and / or a molecular weight distribution of the second resin. Here, the physical properties may be, for example, surface energy, melt viscosity or solubility parameter. Although a mixture of resins containing two kinds of resins is described in this specification, it will be apparent to those skilled in the art that three or more kinds of resins having different physical properties may be mixed and subjected to melt processing.

According to one embodiment, the resin mixture may comprise a first resin and a second resin having a surface energy difference from 0.1 to 35 mN / m at 25 占 폚 with said first resin.

The surface energy difference between the first resin and the second resin is 0.1 to 35 mN / m, 0.1 to 30 mN / m, 0.1 to 20 mN / m, 0.1 to 15 mN / m, 0.1 to 7 mN / , 1 to 35 mN / m, 1 to 30 mN / m, 2 to 20 mN / m, 3 to 15. When the first and second resins having a surface energy difference in this range are used, the first resin and the second resin can not easily peel off, and the second resin can easily move to the surface, and the layer separation phenomenon can easily occur.

The resin mixture of the first resin and the second resin having a surface energy difference of 0.1 to 35 mN / m at 25 DEG C can be layered by melt processing. As an example, when the resin mixture of the first resin and the second resin is melt-processed and exposed to the air, the first resin and the second resin can be separated by a difference in hydrophobicity. In particular, since the second resin having a lower surface energy than the first resin has a high hydrophobicity, it can move in contact with air to form a second resin layer positioned on the air side. In addition, the first resin can be placed on the opposite side of the air while contacting the second resin. Thus, layer separation occurs between the first resin and the second resin of the resin mixture.

The resin mixture may be separated into two or more layers. As one example, the resin mixture comprising the first resin and the second resin may have three layers, for example, a second resin layer and a second resin layer, when two opposing faces of the melt- / First resin layer / second resin layer. On the other hand, when only one side of the melt-processed resin mixture is exposed to air, the resin mixture can be layered into two layers, for example, a second resin layer / first resin layer. Further, when the resin mixture comprising the first resin, the second resin and the third resin having the difference in surface energy is melt-processed, the melt-processed resin mixture has five layers, for example, the third resin layer / 2 resin layer / first resin layer / second resin layer / third resin layer. Further, when all surfaces of the melt-processed resin mixture are exposed to air, the resin mixture may be layered in all directions to form a core-shell structure.

According to another embodiment, the resin mixture comprises a first resin; And a second resin having a melt viscosity difference of 0.1 to 3000 pa * s with the first resin at a shear rate of 100 to 1000 s < ^-1 > and a processing temperature of the resin mixture.

The difference between the melt viscosity of the first resin and the second resin is from 100 to 1000 s ^-1 shear rate and the processing temperature of the resin mixture of from 0.1 to 3000 pa * s, 1 to 2000 pa * s, 1 to 1000 pa * s, 1 to 500 pa * s, 50 to 500 pa * s, 100 to 500 pa * s, 200 to 500 pa * s, or 250 to 500 pa * s. In the case of using the first and second resins having a difference in melt viscosity in this range, the first resin and the second resin can not easily peel off, and the second resin can easily move to the surface and the layer separation phenomenon can easily occur.

The resin mixture of the first resin and the second resin having a melt viscosity difference of 0.1 to 3000 pa * s at a shear rate of 100 to 1000 s < ^-1 > and a processing temperature of the resin mixture is melt- Can be separated. As one example, when the resin mixture of the first resin and the second resin is melt-processed and exposed to the air, the first resin and the second resin can be separated by the fluidity difference. In particular, since the second resin having a lower melt viscosity than the first resin has high fluidity, it can move in contact with air to form a second resin layer located on the air side. In addition, the first resin can be placed on the opposite side of the air while contacting the second resin. Thus, layer separation occurs between the first resin and the second resin of the resin mixture.

The melt viscosity can be measured by capillary flow, which means the shear viscosity (pa * s) according to the specific processing temperature and shear rate (/ s).

The 'shear rate' refers to the shear rate applied when the resin mixture is processed, and the shear rate can be controlled between 100 and 1000 s ^-1 , depending on the processing method. Control of the shear rate according to the processing method will be apparent to those skilled in the art.

The 'processing temperature' means a temperature at which the resin mixture is processed. For example, when the resin mixture is used for melt processing such as extrusion or injection, it means a temperature applied to the melt processing step. The processing temperature can be controlled according to the resin used for melt processing such as extrusion or injection molding. For example, in the case of a resin mixture comprising a first resin of ABS resin and a second resin obtained from an acrylic monomer, the processing temperature may be 210 to 270 캜.

According to another embodiment of the present invention, there is provided a resin composition comprising: a first resin; And a second resin having a solubility parameter difference of 0.001 to 10.0 (J / cm ³ ) ^1/2 with the first resin at 25 ° C.

The first resin and the solubility parameter of the second resin (Solubility Parameter) is a difference in the 25 ℃ 0.001 to ^{10.0 (J / cm 3) 1/2} , 0.01 to ^{5.0 (J / cm 3) 1/2} , 0.01 to 3.0 ( J / cm ^{3) 1/2,} 0.01 to ^{2.0 (J / cm 3) 1/2} , 0.1 to ^{1.0 (J / cm 3) 1/2} , 0.1 to ^{10.0 (J / cm 3) 1/2} , 3.0 to 10.0 (J / cm ³⁾ may be ^one-half, from 5.0 to 10.0 (J / cm ^{3) 1/2,} or from 3.0 to ^{8.0 (J / cm 3) 1/2} . These solubility parameters are inherent characteristics of the resin showing the dissolution possibility according to the polarity of each resin molecule, and the solubility parameter for each resin is generally known. When the solubility parameter difference is ^less than 0.001 (J / cm ³ ) ^1/2 , the first resin and the second resin are easily miscible and the layer separation phenomenon is difficult to occur easily. When the solubility parameter difference is 10.0 (J / cm < ³ >) ^1/2 , the first resin and the second resin can not be bonded and can be peeled off.

The upper limit and / or lower limit of the solubility parameter difference may be any value within a range of 0.001 to 10.0 (J / cm < ³ &^gt;) ^1/2 and may depend on the physical properties of the first resin. In particular, when the first resin is used as a base resin and the second resin is used as a functional resin for improving the surface characteristics of the first resin, the second resin has a solubility parameter difference between the first resin and the second resin of 25 DEG C (J / cm < ³ >)< ^1/2 > As an example, the difference in solubility parameter can be selected in consideration of the miscibility of the second resin in the molten mixture of the first resin and the second resin.

At 25 캜, the resin mixture of the first resin and the second resin having a solubility parameter difference of 0.001 to 10.0 (J / cm ³ ) ^1/2 can be layered due to the difference in solubility parameter after melt processing. As one example, when the resin mixture of the first resin and the second resin is melt-processed and exposed to the air, the first resin and the second resin can be separated by the degree of miscibility. In particular, the second resin having a solubility parameter difference of from 0.001 to 10 (J / cm ³ ) ^1/2 at 25 ° C relative to the first resin may not be miscible with the first resin. Therefore, if the second resin additionally has a lower surface tension or lower melt viscosity than the first resin, the second resin can move to contact the air to form a second resin layer located on the air side. In addition, the first resin can be placed on the opposite side of the air while contacting the second resin. Thus, layer separation occurs between the first resin and the second resin of the resin mixture.

In the resin mixture, the first resin is a resin which mainly determines the physical properties of a desired molded article, and may be selected according to the type of the desired molded article and the process conditions to be used. As the first resin, a general synthetic resin can be used without any particular limitation.

Examples of the first resin include styrene resins such as ABS (acrylonitrile butadiene styrene) resin, polystyrene resin, acrylonitrile styrene acrylate (ASA) resin and styrene-butadiene-styrene block copolymer; A polyolefin-based resin such as a high-density polyethylene-based resin, a low-density polyethylene-based resin, or a polypropylene-based resin; A thermoplastic elastomer such as an ester-based thermoplastic elastomer or an olefin-based thermoplastic elastomer; Polyoxyalkylene resins such as polyoxymethylene resins and polyoxyethylene resins; Polyester resins such as polyethylene terephthalate resin or polybutylene terephthalate resin; Polyvinyl chloride resins; Polycarbonate resin; Polyphenylene sulfide type resin; Vinyl alcohol type resin; Polyamide based resin; Acrylate resins; Engineering plastics; Copolymers thereof, and mixtures thereof. As the engineering plastics, plastics exhibiting excellent mechanical and thermal properties can be used. For example, polyether ketone, polysulfone, and polyimide may be used as engineering plastics. In one example, the first resin may be a copolymer obtained by polymerizing acrylonitrile, butadiene, styrene, and acrylic monomers.

The second resin in the resin mixture may be a reaction product of an acrylic polymer having a functional group and a polyolefin resin having a reactive group capable of reacting with the functional group.

In one example, the second resin may be prepared by a method of reactively extruding an acrylic polymer having a functional group and a polyolefin resin having a reactive group capable of reacting with the functional group. A functional group is present in the acrylic polymer, and a polyolefin resin exists in the reactor capable of reacting with the functional group. By properly controlling the reactive functional groups of the acrylic polymer and the inorganic particles and subjecting the resultant to a reactive extrusion process, a composite resin having a structure in which the polyolefin resin is bonded to an acrylic polymer can be provided.

The functional groups present in the acrylic polymer and the reactors present in the polyolefin can be present in pairs that can react with each other in a reactive extrusion process. The functional groups and the reactive groups present in the acrylic polymer and the polyolefin may be, for example, any of a carboxyl group, a hydroxyl group, an amino group and an anhydride group, and may exist in a pair capable of reacting with each other. That is, the functional group may be at least one selected from the group consisting of a carboxyl group, a hydroxyl group, an amino group and an anhydride group, and the reactor may be an organic group capable of reacting with the functional group. In one example, when the reactive functional group present in the acrylic polymer is a carboxyl group, the reactive functional group present in the polyolefin may be an amino group. Further, in another example, when the reactive functional group present in the acrylic polymer is a hydroxyl group, the reactive functional group present in the polyolefin may be an anhydride group.

If a reactor of a functional group and a polyolefin an acrylic polymer combined in a reaction extrusion process the acrylic polymer and the polyolefin containing the divalent organic linker, for _{example, -CONH-, -CONR a -, -COOCO-} , -OCONH-, -OCONR a -, -COO-, -NH-, or -NR _a - bonds. Wherein R < _a > may be an alkyl group having 1 to 16 carbon atoms.

In the above, the reactive extrusion process may mean, for example, a process in which a reaction takes place inside an extruder during an extrusion process. This reaction extrusion process can be carried out using a commonly used extruder.

In the reactive extrusion process, the temperature condition of the process can be adjusted according to the kind of the linear polymer used. In one example, a reactive extrusion process may be performed at a temperature of at least about 150 degrees, at least about 200 degrees, or at least about 220 degrees.

In the reactive extrusion process, the shear rate can also be controlled depending on the kind of acrylic polymer and polyolefin used, and the shear rate required for sufficient reaction and mixing can be selected and controlled. If sufficient mixing is required, a twin screw compressor can be used.

The content of the acrylic polymer having a functional group and the polyolefin having a reactive group can be appropriately adjusted in consideration of the purpose of use and the like. In one example, the weight ratio of the acrylic polymer to the polyolefin may be in the range of 60 to 99: 1 to 40, 65 to 97: 3 to 35 in order to exhibit a hardness suitable for use as the surface layer of the molded resin article.

In one example, as the acrylic polymer, those prepared by polymerizing a monomer mixture containing an acrylic monomer having a functional group and an alkyl (meth) acrylate can be used. Polymers prepared in this way may have reactive functional groups capable of bonding with reactive polyolefins, that is, reactive polyolefins along the main chain.

The acrylic monomer having a functional group is a monomer for introducing a functional group for bonding the reactive polyolefin into the acrylic polymer. Examples of the acrylic monomer having such a functional group include an acrylic monomer having a carboxyl group, an acrylic monomer having a hydroxyl group, an acrylic monomer having an amino group, or an acrylic monomer having an anhydride group.

Specific examples of the acrylic monomer having a reactive functional group include (meth) acrylic acid, 2- (meth) acryloyloxyacetic acid, 3- (meth) acryloyloxypropyl acid, 4- (meth) acryloyloxybutyl Acrylic monomers having a carboxyl group such as an acid, (meth) acrylic acid dimer, itaconic acid or maleic acid; (Meth) acrylamide or N-substituted (meth) acrylamide; Hydroxy-C _{1 - 14} alkyl (meth) acrylate monomer having a hydroxyl group such as acrylate; Or an acrylic monomer having an anhydride group such as maleic anhydride.

The content of the acrylic monomer having a functional group can be controlled according to the content of the reactive polyolefin to be introduced into the resin. For example, in order to apply the polyolefin resin to the surface layer of the resin molded article to exhibit excellent scratch resistance, the acrylic monomer having a reactive functional group is added in an amount of 3 to 50 parts by weight, preferably 5 to 50 parts by weight, based on 100 parts by weight of the total monomers contained in the monomer mixture, 40 parts by weight, and 10 parts by weight to 35 parts by weight.

The alkyl (meth) acrylate may be a monomer that forms the predominant polymerization unit of the acrylic polymer. Examples of such alkyl (meth) acrylates include alkyl of 1 to 40 carbon atoms, alkyl of 1 to 30 carbon atoms, alkyl of 1 to 20 carbon atoms, alkyl of 1 to 10 carbon atoms, alkyl of 1 to 5 carbon atoms, Alkyl of 1 to 3 carbon atoms or alkyl (meth) acrylate of 1 to 2 carbon atoms can be used. The content of the alkyl (meth) acrylate forming the main polymerization unit of the acrylic polymer can be appropriately controlled depending on the use of the inorganic particle-containing resin. For example, the content of the alkyl (meth) acrylate may be in the range of 50 to 97 parts by weight, 60 to 95 parts by weight, 65 to 90 parts by weight, 50 to 80 parts by weight, 50 to 80 parts by weight based on 100 parts by weight of the total monomers contained in the monomer mixture 50 to 70 parts by weight, 55 to 80 parts by weight, 60 to 80 parts by weight, 55 to 75 parts by weight or 60 to 70 parts by weight.

In one example, the monomer mixture for polymerizing the acrylic polymer may further comprise a monomer having a bulky functional group. A linear polymer formed from a monomer mixture comprising monomers having bulky functional groups may increase the hydrodynamic volume to provide a second resin having a lower melt viscosity.

In one example, the monomer having a bulky functional group may be an alkyl (meth) acrylate. The monomer mixture may thus be, for example, an alkyl (meth) acrylate forming the predominant polymerization unit of the acrylic polymer described above; And (meth) acrylates having a bulky alkyl group. Examples of the (meth) acrylate having a bulky alkyl group include a vinyl group having 3 to 20 carbon atoms, 3 to 12 carbon atoms, 3 to 6 carbon atoms, 5 to 20 carbon atoms, 7 to 20 carbon atoms, 10 to 20 carbon atoms, Alkyl (meth) acrylate of 20 to 20 carbon atoms; Or an alicyclic (meth) acrylate having 5 to 40 carbon atoms, 5 to 25 carbon atoms, 5 to 16 carbon atoms, 6 to 40 carbon atoms, 10 to 40 carbon atoms, 12 to 40 carbon atoms or 16 to 40 carbon atoms, And the like. Specific examples of the alkyl (meth) acrylate having 3 to 20 carbon atoms include isopropyl (meth) acrylate, isobutyl (meth) acrylate, tertiary butyl (meth) Examples of the alicyclic (meth) acrylate having 5 to 40 carbon atoms include cyclohexyl (meth) acrylate or isobornyl (meth) acrylate, And the like.

The content of the (meth) acrylate having a bulky alkyl group can be appropriately controlled depending on the melt viscosity and purpose of use of the polyolefin resin. For example, the content of the (meth) acrylate having a bulky alkyl group may be 10 to 40 parts by weight, 15 to 40 parts by weight, 20 to 40 parts by weight, 10 to 35 parts by weight based on 100 parts by weight of the total monomers contained in the monomer mixture, 10 to 30 parts by weight, 15 to 35 parts by weight or 20 to 30 parts by weight.

In another example, aromatic (meth) acrylate may be used as the monomer having a bulky functional group. Examples of the aromatic (meth) acrylate include aromatic (meth) acrylates having 6 to 40 carbon atoms, 6 to 25 carbon atoms, and 6 to 16 carbon atoms. Examples of the aromatic (meth) acrylate having 6 to 40 carbon atoms include naphthyl (meth) acrylate, phenyl (meth) acrylate, anthracenyl (meth) Acrylate or benzyl (meth) acrylate can be used.

The content of such aromatic (meth) acrylates can be suitably controlled in accordance with the intended use of the polyolefin resin, such as (meth) acrylate having the aforementioned bulky alkyl group. For example, the content of the aromatic (meth) acrylate may be 10 to 40 parts by weight, 15 to 40 parts by weight, 20 to 40 parts by weight, 10 to 35 parts by weight 10 to 10 parts by weight based on 100 parts by weight of the total monomers contained in the monomer mixture, 30 parts by weight, 15 to 35 parts by weight or 20 to 30 parts by weight.

The monomer mixture comprising the above-described monomers can generally provide an acrylic polymer in a manner that produces a resin through polymerization of the monomers. For example, the monomer mixture may be polymerized by a method such as bulk polymerization, solution polymerization, suspension polymerization, or emulsion polymerization to provide a linear polymer.

In one example, a method of making an acrylic polymer includes dispersing a dispersant in a solvent; Dispersing the above-mentioned monomer mixture in the solvent; Adding an additive such as a chain transfer agent and / or an initiator to the solvent and mixing them; And a polymerization step of reacting at a temperature of 40 DEG C or higher. Herein, the order of each step can be changed arbitrarily, and it is also possible to carry out two or more steps to one step.

The solvent can be used without limitation as long as it is a medium known to be routinely usable for preparing polymers. As such a solvent, for example, methyl ethyl ketone, ethanol, methyl isobutyl ketone, or distilled water may be used, or two or more kinds thereof may be mixed and used.

Examples of the dispersing agent that can be added to the solvent include organic dispersing agents such as polyvinyl alcohol, polyolin-maleic acid or cellulose; Or an inorganic dispersant such as tricalcium phosphate.

Examples of the chain transfer agent include alkyl mercaptans such as n-butylmercaptan, n-dodecylmercaptan, tertiary dodecylmercaptan or isopropylmercaptan; Arylmercaptan such as phenylmercaptan, naphthylmercaptan or benzylmercaptan; Halogen compounds such as carbon tetrachloride; Alpha-methylstyrene dimer, and alpha-ethyl styrene dimer.

Examples of the initiator include peroxides such as octanoyl peroxide, decanoyl peroxide and lauroyl peroxide; azo compounds such as azobisisobutyronitrile and azobis- (2,4-dimethyl) -valeronitrile; Azo compounds and the like.

In addition, an additive conventionally used in the polymer industry may be used in the production of the acrylic polymer, and a conventionally performed process may be further performed.

The polyolefin to be introduced into the acrylic polymer includes, but is not limited to, an acid-modified polyolefin or an amino-modified polyolefin.

In one embodiment, the acid-modified polyolefin is prepared by reacting an unsaturated carboxylic acid, such as maleic acid, maleic anhydride, acrylic acid, methacrylic acid, citraconic acid, citraconic anhydride, itaconic acid, or itaconic anhydride, or an anhydride thereof with olefins and grafts ) Copolymerization reaction.

In one example, the weight average molecular weight (Mw) of the second resin can be from about 5,000 to about 200,000. In another example, the weight average molecular weight of the inorganic particle-containing resin is from 10,000 to 200,000, from 150,000 to 200,000, from 20,000 to 200,000, from 0.5 million to 180,000, from 0.5 million to 150,000, from 0.5 million to 120,000, From about 1 million to about 180,000, from about 150,000 to about 150,000, or from about 20,000 to about 120,000. When a second resin having a weight average molecular weight in this range is applied to, for example, a resin mixture for melt processing, the second resin has an appropriate fluidity so that layer separation can easily occur.

Further, in one example, the molecular weight distribution (PDI) of the second resin can be controlled in the range of 1 to 2.5, 1 to 2.2, 1.5 to 2.5, or 1.5 to 2.2. When the second resin having a molecular weight distribution in this range is applied to, for example, a resin mixture for melt processing, the content of the low molecular weight compound and / or the high molecular weight material which impedes the occurrence of layer separation in the second resin is reduced, Can happen.

In one example, the resin mixture may comprise 0.1 to 50 parts by weight of the second resin based on 100 parts by weight of the first resin. Further, in another example, the resin mixture may include 1 to 30 parts by weight, 1 to 20 parts by weight or 1 to 15 parts by weight based on 100 parts by weight of the first resin. When the first resin and the second resin are included in such a content, the layer separation phenomenon can be induced, and the content of the second resin, which is relatively high compared to the first resin, can be appropriately controlled to provide an economical resin mixture.

The resin mixture described above can be made into pellets by extrusion. In the pellet produced using the resin mixture, the first resin forms a core and the second resin separates from the first resin to form a shell.

According to one embodiment, the pellet comprises a core formed of a first resin; And a reaction product of a polyolefin resin having a reactive group capable of reacting with an acrylic polymer having a functional group and a second resin having a difference in surface energy, melt viscosity or solubility parameter from the first resin The pellet is provided.

In addition, as described above, the first resin and the second resin may have different surface energy, melt viscosity, or solubility parameters. For example, the first resin and the second resin may have a surface energy difference of from 0.1 to 35 mN / m at 25 占 폚; Or a melt viscosity difference of from 0.1 to 3000 pa * s at a shear rate of from 100 to 1000 s < ^-1 > and a processing temperature of the pellet.

The types and physical properties of the first resin and the second resin have already been described in detail, and the detailed description thereof will be omitted.

On the other hand, the above-mentioned resin mixture or pellet can be melt-processed to provide a resin molded article having a layer separation structure.

According to one embodiment, there is provided a method for producing a melt blend, comprising: melting a resin mixture to form a melt blend; And a step of processing the molten mixture to form a layered structure.

As described above, due to the difference in physical properties between the first resin and the second resin, a layer separation phenomenon may occur during the melt-processing of the resin mixture. Due to such layer separation phenomenon, The effect of selectively coating the surface of the molded article can be obtained.

Particularly, when the reactant of the acrylic polymer and the polyolefin resin is used as the second resin, the reaction product of the acrylic polymer and the polyolefin resin having a relatively low surface energy or melt viscosity during the melt processing step is located on the surface of the resin molded article, A resin molded article having improved surface characteristics can be provided.

The step of melt-working the resin mixture can be carried out under shear stress. For example, the step of melt-working can be carried out by an extrusion and / or an injection-molding method.

Further, in the step of melt-processing the resin mixture, the applied temperature may be different depending on the kind of the first resin and the second resin used. For example, when a styrene resin is used as the first resin and an acrylic resin is used as the second resin, the melt processing temperature can be controlled to about 210 to 270 degrees.

The method may further include the step of curing the resulting product obtained by melt-processing the resin mixture, that is, the melt-processed product of the resin mixture. The curing may be, for example, thermal curing or UV curing. The resin molded article may further be subjected to chemical or physical treatment.

In one example, the manufacturing method of the resin molded article may further include the step of producing the second resin before the step of melting the resin mixture to form the molten mixture. The second resin can impart a specific function, for example, high hardness, to the surface layer of the resin molded article. The contents related to the production of the second resin have already been described, and a detailed description thereof will be omitted.

According to another embodiment, a method of manufacturing a resin molded article includes melting a pellet to form a molten mixture; And processing the molten mixture to form a layered structure.

In one example, the pellets may be prepared by melt-processing the above-mentioned resin mixture, such as extrusion. For example, when a resin mixture comprising the first resin and the second resin is extruded, a second resin having a higher hydrophobicity than the first resin moves to contact with the air to form a shell of the pellet, 1 < / RTI > resin may be located at the center of the pellet to form a core. The pellets thus produced can be made into a resin molded article by melt processing such as injection molding. However, the present invention is not limited thereto. In another example, the resin mixture may be directly molded into a resin molded product by melt processing such as injection molding or the like.

On the other hand, according to another embodiment, the resin molded article has a first resin layer, a second resin layer formed on the first resin layer, and an interface layer formed between the first resin layer and the second resin layer . ≪ / RTI > The interfacial layer may comprise first and second resins and the second resin may comprise a reactant of a polyolefin resin having an acrylic polymer having a functional group and a reactor capable of reacting with the functional group have.

A resin molded product produced from a resin mixture comprising a specific first resin and the second resin having a difference in physical properties from the first resin is obtained by, for example, a method in which a first resin layer is located inside and a second resin layer is a resin Or may be a layered structure formed on the surface of the molded article.

Particularly, when the reactant of the acrylic polymer and the polyolefin resin is used as the second resin, the molded article can further improve the surface hardness.

The 'first resin layer' mainly includes the first resin, determines the physical properties of the molded article, and can be located inside the resin molded article. The 'second resin layer' mainly contains the second resin, and can be positioned outside the resin molded product to give a certain function to the surface of the molded product.

The details of the first resin and the second resin have already been described above, and a description of the related contents will be omitted.

The resin molded article may include an interface layer formed between the first resin layer and the second resin layer and including a mixture of the first resin and the second resin. The interface layer may be formed between the layered first resin layer and the second resin layer to serve as an interface, and may include a mixture of the first resin and the second resin. The first resin and the second resin may be physically or chemically bonded to each other, and the first resin layer and the second resin layer may be bonded to each other through the mixture.

The resin molded article may be formed in such a structure that the first resin layer and the second resin layer are separated by the interface layer and the second resin layer is exposed to the outside. For example, the molded article may include the first resin layer; Interfacial layer; And the second resin layer may be sequentially stacked, and may be a structure in which the interface and the second resin are laminated on the upper and lower ends of the first resin. The resin molded article may include a structure in which the interface and the second resin layer sequentially surround a first resin layer having various shapes, for example, spherical, circular, polyhedral, sheet, or the like.

Layer separation phenomenon appearing in the resin molded article appears to be due to the production of resin molded articles by applying specific first and second resins having different physical properties. Examples of such different physical properties include surface energy or melt viscosity. The details of the difference in physical properties are as described above.

In one example, the first resin layer, the interface layer and the second resin layer can be confirmed by SEM after etching the specimen using a THF vapor after the low-temperature impact test. To measure the thickness of each layer, the specimen is cut with a diamond knife using a microtoming machine to obtain a smooth cross-section, and then a smooth cross-section is etched using a solution that can selectively melt the second resin compared to the first resin. The cross-sectional area of the etched section differs depending on the content of the first resin and the second resin. When the cross section is observed at 45 degrees from the surface using SEM, the first resin layer, the second resin layer, The interface layer and the surface can be observed, and the thickness of each layer can be measured. In one example, a 1,2-dichloroethane solution (10 vol%, in EtOH) was used as a solution for selectively dissolving the second resin, but this is illustrative only and is not intended to limit the solubility of the second resin Solution is not particularly limited, and those skilled in the art can appropriately select and apply the solution according to the type and composition of the second resin.

The interfacial layer may comprise from 1 to 95%, from 10 to 95%, from 20 to 95%, from 30 to 95%, from 40 to 95%, from 50 to 95%, from 60 to 95% of the total thickness of the second resin layer and interfacial layer And may have a thickness of 60 to 90%. If the interface layer has a thickness of 0.01 to 95% of the total thickness of the second resin layer and the interface layer, the interfacial bonding force between the first resin layer and the second resin layer is excellent so that the peeling of both layers does not occur, Can be greatly improved. On the other hand, if the interface layer is too thin as compared with the second resin layer, the bonding force between the first resin layer and the second resin layer is low, so that peeling of both layers may occur. If the interface layer is too thick, The effect of improving the characteristics may be insignificant.

The second resin layer may have a thickness of 0.01 to 30%, 0.01 to 20%, 0.01 to 10%, 0.01 to 5%, 0.01 to 3%, 0.01 to 1%, or 0.01 to 0.1% . When the thickness of the second resin layer is too small, the surface properties of the molded article can be sufficiently improved. [0051] [52] If the thickness of the second resin layer is too large, the mechanical properties of the functional resin itself may be reflected in the resin molded article, and the mechanical properties of the first resin may be changed.

In the resin molded article having the above-described structure, the component of the first resin layer can be detected by the infrared ray spectroscope (IR) at the surface of the second resin layer.

In this case, the surface of the second resin layer means a surface exposed to the outside (for example, air) rather than to the first resin layer.

The details of the first resin, the second resin, and the difference in physical properties between the first resin and the second resin have already been described above, and a description of the relevant contents will be omitted. In this specification, a difference in physical properties between the first resin and the second resin may mean a difference in physical properties between the first resin and the second resin or a difference in physical properties between the first resin layer and the second resin layer.

In one example, the resin molded article can be used for providing automobile parts, helmets, electric appliance parts, spinning machine parts, toys, pipes, and the like.

An exemplary resin mixture of the present application can provide a resin molded article whose surface has improved mechanical properties and surface hardness. In addition, when the resin mixture is used, the additional surface coating step can be omitted on the surface of the resin molded article, and the above-mentioned effect can be exhibited, so that the production time and cost can be reduced and the productivity can be increased.

Fig. 1 is a SEM photograph showing a layered sectional shape of the resin molded article produced in Example 1. Fig.

Hereinafter, the resin mixture will be described in detail by way of examples and comparative examples, but the range of the resin mixture is not limited by the examples given below.

The physical properties in the following examples and comparative examples were evaluated in the following manner.

1. Measurement of surface energy

Based on the Owens-Wendt-Rabel-Kaelble method, the surface energy was measured using a Drop Shape Analyzer (DSA100 from KRUSS).

Specifically, the resin obtained in Example or Comparative Example was dissolved in methyl ethyl ketone solvent in a concentration of 15% by weight, the precipitate was removed using a centrifugal separator, and bar coating was performed on LCD glass ). The coated LCD glass was preliminarily dried in an oven at 60 DEG C for 2 minutes and dried in an oven at 90 DEG C for 1 minute.

After the drying (or curing), deionized water and diiodomethane were dropped 10 times on the coated surface to obtain the average value of the contact angle, and the surface energy was obtained by substituting the values into the Owens-Wendt-Rabel-Kaelble method.

2. Pencil hardness measurement experiment

The surface pencil hardness of the specimens obtained in the Examples and Comparative Examples was measured under a constant load of 500 g by using a pencil hardness tester (degree test machine, Korea). A standard pencil (manufactured by Mitsubishi) was changed from 6B to 9H while maintaining an angle of 45 degrees, and scratches were applied to observe the rate of change of the surface (ASTM 3363-74). The measurement result is the average value of the results of five repeated experiments.

3. Observing cross-sectional shape

After the samples of Examples and Comparative Examples were subjected to a low-temperature impact test, the fractured surfaces were etched by using THF vapor and the sectional shapes separated by SEM (manufacturer: Hitachi, model: S-4800) were observed. The observed cross-sectional shape is shown in Fig.

Manufacturing example  One

1500 g of distilled water and 4 g of a 2% aqueous solution of polyvinyl alcohol as a dispersant were added and dissolved in a 3-liter reactor. Subsequently, 240 g of methyl methacrylate, 560 g of hydroxyethyl methacrylate, 2.4 g of n-dodecylmercaptan, which is a chain transfer agent, and 2.4 g of azobisdimethylvaleronitrile as an initiator were further charged into the reactor, and the mixture was stirred at 400 rpm And dispersed in water. The mixture was reacted at 60 캜 for 3 hours to polymerize, and cooled to 30 캜 to obtain resin (A) in bead form. Subsequently, the resin (A) was washed three times with distilled water, dehydrated and then dried in an oven.

Manufacturing example  2

10 parts by weight of maleic anhydride grafted polyethylene resin (Dupont Fusabond E588) and 90 parts by weight of the resin prepared in Preparation Example 1 were mixed and extruded at a temperature of 240 DEG C using a twin-screw extruder of Leistritz, ≪ / RTI >

Example  One

90 parts by weight of a first resin (a thermoplastic resin consisting of 60 parts by weight of methyl methacrylate, 7 parts by weight of acrylonitrile, 10 parts by weight of butadiene and 23 parts by weight of styrene) and 10 parts by weight of the second resin prepared in Preparation Example 2 And then extruded at a temperature of 240 DEG C in a twin-screw extruder (Leistritz) to obtain a pellet. Then, these pellets were injected at an extrusion temperature of 240 DEG C in an EC100P0 extruder (manufactured by ENGEL) to produce a specimen of molded resin having a thickness of 3200 mu m.

The surface energy difference between the first resin and the second resin was 7 mN / m. The pencil hardness of the specimen was 2H, and a layer separation phenomenon was observed in the specimen. A cross-sectional SEM photograph of the specimen is shown in Fig. The thickness of the second resin layer of the specimen was 60 占 퐉, and the thickness of the interface layer was 16 占 퐉.

Example  2

A specimen was prepared in the same manner as in Example 1, except that 30 parts by weight of maleic anhydride grafted polyethylene resin (Dupont Fusabond E588) and 70 parts by weight of the resin prepared in Preparation Example 1 were mixed.

The surface energy difference between the first resin and the second resin was 10 mN / m. The pencil hardness of the specimen was 1.5H, and a layer separation phenomenon was observed in the specimen. The thickness of the second resin layer of the specimen was 68 占 퐉, and the thickness of the interface layer was 8 占 퐉.

Example  3

A specimen was prepared in the same manner as in Example 1, except that 5 parts by weight of maleic anhydride grafted polyethylene resin (Dupont Fusabond E588) and 95 parts by weight of the resin prepared in Preparation Example 1 were mixed.

The difference in surface energy between the first resin and the second resin was 5 mN / m. The pencil hardness of the specimen was H, and the layer separation phenomenon was observed in the specimen. The thickness of the second resin layer of the specimen was 51 mu m, and the thickness of the interface layer was 20 mu m.

Comparative Example  One

100 parts by weight of the first resin used in Example 1 was dried in an oven and injected at a temperature of 240 DEG C in an EC100? 30 extruder (manufactured by ENGEL) to prepare a molded resin product specimen.

In the above specimen, no layer separation phenomenon was observed and the surface hardness was F. [

Comparative Example  2

Specimens were prepared in the same manner as in Example 1, except that 90 parts by weight of the first resin used in Example 1 and 10 parts by weight of the resin (A) prepared in Preparation Example 2 were mixed.

The difference in surface energy between the first resin and the second resin was 2 mN / m. The pencil hardness of the specimen was F, and a layer separation phenomenon was observed in the specimen. The thickness of the second resin layer of the specimen was 2 mu m, and the interface layer was not measurable.

Claims (14)

A first resin; And a second resin which is a reactant of an acrylic polymer having a hydroxyl group and a polyolefin resin having an anhydride group which is an organic group capable of reacting with the hydroxyl group,
The second resin has a difference in surface energy, melt viscosity or solubility parameter from the first resin,
Wherein the weight ratio of the acrylic polymer to the polyolefin is from 60 to 99: 1 to 40,
Wherein the acrylic polymer is a polymer of a monomer mixture comprising an acrylic monomer having a hydroxyl group and an alkyl (meth) acrylate, wherein the acrylic monomer having a hydroxy group is contained in an amount of 3 to 50 parts by weight based on 100 parts by weight of the total monomers contained in the monomer mixture ,
Wherein the polyolefin is a maleic anhydride-modified polyolefin. The resin mixture according to claim 1, wherein the second resin has a surface energy difference of 0.1 to 35 mN / m with the first resin at 25 占 폚. The resin composition according to claim 1, wherein the first resin which is an ABS resin and the second resin which is obtained from an acrylic monomer have a shear rate of 100 to 1000s < ^-1 > and a resin having a difference in melt viscosity of 0.1 to 3000 pa * mixture. The resin mixture according to claim 1, wherein the second resin has a solubility parameter difference of 0.001 to 10.0 (J / cm ³ ) ^1/2 with the first resin at 25 ° C. The resin composition according to claim 1, wherein the first resin is selected from the group consisting of a styrene resin, a polyolefin resin, a thermoplastic elastomer, a polyoxyalkylene resin, a polyester resin, a polyvinyl chloride resin, a polycarbonate resin, Vinyl alcohol resin, polyamide resin, acrylate resin, copolymer thereof, or a mixture thereof. delete delete delete delete delete The resin mixture according to claim 1, wherein the second resin has a molecular weight distribution of 1 to 2.5. The resin mixture according to claim 1, wherein the second resin has a weight average molecular weight of 5,000 to 200,000. The resin mixture according to claim 1, comprising 0.1 to 50 parts by weight of a second resin based on 100 parts by weight of the first resin. A core formed of a first resin; And a reaction product of an acrylic polymer having a hydroxyl group and a polyolefin resin having an anhydride group which is an organic group capable of reacting with the hydroxyl group, and having a surface energy, a melt viscosity or a solubility parameter different from that of the first resin, ≪ / RTI &
Wherein the weight ratio of the acrylic polymer to the polyolefin is from 60 to 99: 1 to 40,
Wherein the acrylic polymer is a polymer of a monomer mixture comprising an acrylic monomer having a hydroxyl group and an alkyl (meth) acrylate, wherein the acrylic monomer having a hydroxy group is contained in an amount of 3 to 50 parts by weight based on 100 parts by weight of the total monomers contained in the monomer mixture ,
Wherein the polyolefin is a maleic anhydride-modified polyolefin.

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