[go: up one dir, main page]
More Web Proxy on the site http://driver.im/

MXPA99004317A - Tpo blends containing multimodal elastomers - Google Patents

Tpo blends containing multimodal elastomers

Info

Publication number
MXPA99004317A
MXPA99004317A MXPA/A/1999/004317A MX9904317A MXPA99004317A MX PA99004317 A MXPA99004317 A MX PA99004317A MX 9904317 A MX9904317 A MX 9904317A MX PA99004317 A MXPA99004317 A MX PA99004317A
Authority
MX
Mexico
Prior art keywords
mixture
molecular weight
weight
mode
elastomer
Prior art date
Application number
MXPA/A/1999/004317A
Other languages
Spanish (es)
Inventor
K Laughner Michael
Srinivasan Satchit
Szczepaniak Edward
Her Jhyyuan
P Karjala Teresa
Original Assignee
Dupont Dow Elastomers Llc
Solvay Engineered Polymers
The Dow Chemical Company
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Dupont Dow Elastomers Llc, Solvay Engineered Polymers, The Dow Chemical Company filed Critical Dupont Dow Elastomers Llc
Publication of MXPA99004317A publication Critical patent/MXPA99004317A/en

Links

Abstract

Thermoplastic polyolefin blends having improved resistance to fluids such as petroleum fuels after being painted with flexible coatings such as polyurethanes paints and the like are disclosed. These blends include a crystalline or semi-crystalline polyolefin such as polyethylene, polypropylene, or a copolymer of ethylene and a C3 to C10 olefin, and a multimodal elastomer of sequentially polymerized ethylene-&agr;-olefin monomers. The substantially crystalline polyolefin is present in an amount of 30 to 98 weight percent, while the multimodal elastomer, which is substantially amorphous, is present in an amount of about 2 to 70 weight percent. The blends may contain additional polymeric components, fillers and the like. In addition to increased paint adherence, higher weld-line strength, low temperature ductility and processability can be achieved.

Description

TPO MIXES CONTAINING MULTIMODAL ELASTOMERALS TECHNICAL FIELD The present invention relates to thermoplastic polyolefin ("TPO") blends that include a crystalline or crystalline polyolefin and a multimodal elastomer, preferably a sequentially polymerized ethylene-alpha-olefin copolymer. which has a multimodal distribution of at least one of the molecular weight, density or alpha-olefin comonomers. BACKGROUND OF THE INVENTION Various mixtures of TPO are molded into lightweight and durable articles that are useful as auto parts, equipment racks, toys and the like. Frequently, it is desired to paint these components for aesthetic or functional purposes. When these mixtures contain combinations of crystalline and semicrystalline polymers and elastomers, however, the surface of the molded article must generally be treated in such a way that the paint can adhere in a durable manner to the article. The adhesion of the paint is a particular concern in articles molded from mixtures of TPO as described in US Patents 4,480,065, 4,439,573 and 4,412,016. One way to obtain a good adhesion of the paint is to treat the surface of the article with a coating between layers to promote or increase the adhesion. When the article is to be used in environments that include high humidity conditions, or is exposed to petroleum fuels or solvents, however, interlayer coatings may be adversely affected with reduced paint adhesion as a result. Thus, the paintings will come off during the use of the article. An example of this is the use of a painted molded TPO car fender. Such articles will not be approved for use in automobiles unless the paint retains its proper adhesion properties in the presence of such fluids and moisture. U.S. Patent No. 5,498,671 presents a solution to this problem by using a combination of ethylene / propylene / diene monomers of high and low molecular weights (EPDM) with crystalline or semi-crystalline polyolefins. The resulting TPO mixtures have excellent adhesion to the paints, with superior resistance to oil fluids and moisture. A minor drawback of the system is the use of low molecular weight EPDM which is a viscous, sticky liquid at room temperature. Thus, it is necessary to carefully handle this viscous fluid, for example by keeping it in plastic bags or by pumping it to facilitate its introduction in an external mixer that mixes the components together.
It would be desirable to preserve the good adhesion of the paint of such materials, while improving the ease of handling of the components during the manufacture of the mixture. COMPENDIUM OF THE INVENTION The present invention relates to a thermoplastic polyolefin blend that includes a polyolefin component of a substantially crystalline polymer in an amount of about 30 to 98% by weight of the mixture; and an elastomer of a sequentially polymerized ethylene-alpha-olfephine copolymer having a multimodal distribution of at least one of the molecular weight, density, or alpha-olefin monomers, and which is present in an amount of about 2 to 70. % by weight of the mixture. The polyolefin is preferably present in an amount of about 40 to 96, more preferably 50 to 95% by weight of the mixture, and is a crystalline or semi-crystalline polyethylene polymer, polypropylene polymer, or ethylene copolymer and an alpha-olefin C3 to CIQ- The multimodal elastomer is substantially amorphous and preferably present in an amount of about 4 to 60 and more preferably about 5 to 50% by weight. Advantageously, a bimodal elastomer with the different modes present in a ratio of between about 75:25 and 25:75 is employed. In a modality, at least two modes are present that have weight average molecular weight modes that differ by at least about 25,000 and preferably by about 50,000, 100,000 or more. Alternatively one mode may have a molecular weight that is a multiple of at least about 1.5 and preferably 5 and 50 times higher than the molecular weight of the other mode. In a mode known as a "high-low" ratio, one mode has a lower molecular weight of about 30,000 or less and the other mode has a higher molecular weight of at least about 150,000 to provide a non-liquid polymer that can be handled as a solid at room temperature. In another embodiment, known as the "high-high" ratio one mode has a molecular weight of at least about 50,000 and the other has a molecular weight of at least about 100,000. In the "high-high" ratio it is advantageous if one of the molecular weights is about 75,000 and the other molecular weight is about at about 150,000. In another embodiment of the invention, at least two modes having densities differing by at least about 0.005 grams per cubic centimeter (g / cc) are employed. Preferably, one mode has a density greater than 0.85 g / cc, and the other mode has a density less than about 0.96 g / cc, and the difference between the density of the modes is less than about 0.1, preferably less than about 0.05 and more preferably less than 0.03 g / cc. In another embodiment of the invention, at least two modes are used that contain comonomers that differ in length by at least one carbon atom. Preferably, the comonomers of the modes differ in length by at least 2 carbon atoms, and one of them is propene, butene, hexene or octene. The blends of the invention may also include at least one additional polymer component in an amount comprised between about 1 and 20% by weight of the total mixture. At least two different additional polymer components may be present but in a total amount of about 3 and 35% by weight of the mixture. A suitable polymer component is a copolymer of ethylene and a C3 to C0 olefin alpha (from three to ten carbon atoms) or a terpolymer of this copolymer and a diene monomer. Another suitable polymeric component is a copolymer of ethylene and an alpha-olefin made with a Kaminsky or metallocene catalyst. If desired, the mixture may include a filler in an amount of about 1 to 30% by weight of the mixture. Preferred fillers may be used, such as, for example, talc, mica, glass or calcium carbonate. Other conventional additives such as for example nucleation agents, oils and the like may be included, if desired.
The blends can be formed into molded articles having one or more external surfaces, with at least one of the external surfaces including a coating for aesthetic or functional reasons, if desired. While any coating may be employed, it is preferred to use a coating of two-component polyurethane material. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a graphic illustration of the molecular weight distribution (MWD) of a useful bimodal elastomer representing one embodiment of the TPO blends of the invention. DETAILED DESCRIPTION OF THE INVENTION The polyolefin component of the TPO blends of this invention is a polymer or copolymer of crystalline or semi-crystalline polyethylene or polypropylene, either a copolymer of ethylene or an alpha-olefin C3 to Ci 0 • The copolymer may be a random copolymer, a block copolymer or a graft copolymer. The crystallinity of this component can be located within a range of mainly crystalline (above 50%) to fully crystalline (ie, 100%), ie, the crystallinity of a highly crystalline material, or by a sufficient degree of crystallinity to exhibit a partially crystalline or semicrystalline behavior, that is, with a crystallinity comprised between 30% and 70%. When polypropylene is used as this component, it has a crystallinity of about 30 to 98% and preferably about 50 to 80%, as measured by X-ray analysis or solvent extraction. The term "substantially crystalline" is used herein to refer to polymers or copolymers that are crystalline or semi-crystalline. The polyolefin component can be used in an amount between about 30 and 98% by weight of the mixture, preferably in an amount between about 40 and 96% and more preferably in an amount between about 50 and 95%. When mixtures of substantially crystalline polyolefin polymers or polymers are used, the. Total amount will be within these ranges even when the individual amounts of each may vary as desired. The elastomer component is a substantially amorphous copolymer of ethylene and at least one alpha-olefin having between 3 and 18 carbon atoms. The term "substantially amorphous" indicates that the copolymer has a crystallinity of less than 20% by weight. Although any alpha-olefin containing from 3 to 18 carbon atoms can be employed, propene, butene, hexane and particularly octene are preferred. This elastomer component is present in an amount of about 2 to 70, preferably about 4 to 60 and more preferably about 5 to 50% by weight of the mixture. If desired, an additional monomer such as diene can be added. This elastomer component has a multimodal distribution of at least one of the molecular weight, density, or alpha-olefin monomers. There is no theoretical limit to the number of modes that could be present in this component, even when a finite number of 10 modes or less is used in most applications. For the purposes of the preferred embodiments of the present invention, a bimodal distribution will be illustrated. A person with certain skill in the art will know how to produce any desired number of modes in the elastomer by varying the relative amounts of proportions of each mode, and the invention will not be limited to bimodal elastomers for this reason. When a bimodal distribution of elastomers of different molecular weights is provided, one MWD of the elastomer would be of the type illustrated in Figure 1. An experimental product having this distribution is available from The Dow Chemical Company, and is known as C01R02. As shown in figure 1, this product includes a mode having a weight average molecular weight of about 250,000 and another mode having a weight average molecular weight of about 15,000. The multimodal elastomers of the present invention are formed in situ by interpolymerization using multiple reactors or reactor systems and a restriction geometry catalyst system, or a single reactor having multiple steps. Two reactors are conveniently used, even when multiple reactors (ie, more than two) can be used in any type of series or parallel configuration. Suitable configurations of multiple reactors include a loop reactor, spherical reactor, stirred tank reactor, plug-flow tube reactor, or a reaction extruder. If desired, different catalyst systems may be employed in each reactor. For example, a first reactor may employ a restriction geometry catalyst, as described in U.S. Patent No. 5,064,802 while a second reactor may employ a heterogeneous Ziegler catalyst system, in accordance with that described in U.S. Patent 4,314,912. An exemplary in situ interpolymerization system is presented in WO 94/17112. The content of each of these documents is expressly incorporated herein by reference to the extent necessary for a person to understand the methods for making these multimodal elastomers. The present invention relates to the use of these multimodal elastomers in a TPO mixture instead of referring to the various methods for manufacturing these elastomers. Any of a wide range of different properties would be useful for the multimodal elastomeric component of the present TPO blends. In a first embodiment for a multimodal molecular weight elastomer, for example, the lowest molecular weight could be from 3000 to 7000 (specifically 5000), but would generally be between about 10,000 and 20,000 (typically 15,000) or more. The highest molecular weight can reach up to about 350,000 with the existing technology, but is generally above about 150,000, more particularly, above about 160,000 to 180,000. The difference between the lowest and highest molecular weights at least must be significant or measurable. In many cases, the molecular weight will be at least about 1.5 times to between 5 and 50 times higher than the molecular weight of the other. A weight average molecular weight difference of about 25,000 to 50,000 is generally sufficient to offer the advantages of the present elastomer component for most blends. In a second embodiment, suitable multimodal elastomers include those having a lower molecular weight mode of at least 75,000, preferably 85,000, and most preferably 100,000 with a higher molecular weight mode of at least 115,000, preferably 25,000 and more preferably 150,000 highly beneficial multimodal elastomers have lower average weight-average molecular weight mode of more than 100,000 and a more "high" weight average molecular weight mode of more than 200,000.The overall weight average molecular weight of the elastomer is it is therefore within the range of about 85,000 to 350,000 and preferably between about 105,000 to 250,000.The molecular weights can be measured using the method described in US Pat. No. 5,272,236, the content of which is expressly incorporated herein by reference. Multimodal elastomers is providing segments of relatively high densities and low in the elastomer. This is done by providing different types of concentration of alpha-olefin monomers for a sequential reaction with ethylene in the manner previously explained. For example, a low density monomer could be used to provide a global density of a level as low as about 0.85 g / cc when polymerized with ethylene while a high molecular weight component could provide a density of up to about 0.96 g / cc when polymerizes with ethylene. Small deviations between the low and high densities can provide significant differences in the resulting bimodal elastomer. If desired, a difference of at least about 0.003 g / cc is acceptable, even though values of 0.005 g / cc up to 0.1 g / cc can be used. The overall density of the elastomer may vary, but will preferably be less than about 0.95, preferably less than about 0.9, and more preferably less than about 0.87 g / cc. The relative proportion between high density components and low density components in the elastomer can vary within wide ranges. When two different modes are employed, relative amounts of 5:95 to 95: 5 provide measurable differences in values of molecular weights or high and low densities. When more than 95 parts of a component are used, the effect of the other component becomes relatively insignificant. Furthermore, the use of a high amount of one component in comparison with the other is an inefficient use of the second reactor due to the small relative amounts of the second component that must react. Thus, it is typical to employ relative amounts between 75: 25- and 25:75 for bimodal elastomers.
For certain embodiments, relative amounts between 2: 1 and 1: 2 are conveniently formulated and provide beneficial bimodal properties. Thus, a preferred range of about 70:30 to 30:70 is employed. When other multimodal distributions are desired, the relative quantities of each mode vary appropriately. For 5 modes, for example, each component can vary between 10 and 35 parts, provided that the overall proportion reaches 100. As a specific example, a ratio of 10: 15: 20: 20: 35 is possible, but if desired a wide range of other proportions can be employed. It is also possible to use different alpha-olefin monomers to achieve multimodal properties. When this is carried out the alpha-olefin monomers may differ by a carbon atom and preferably by 2.3 or more carbon atoms. Particularly beneficial bimodal elastomers can be made with propene and octene, although other combinations can be used. One way to prepare these elastomers is by adding each monomer in a separate reactor. In the case of a bimodal elastomer, one monomer is added in the first reactor and the second monomer in another reactor. When this has been done, the relative proportions mentioned above can be used to define the relevant amounts of each monomer. Also, a mixture of the monomers can be added to each reactor, with a larger amount of a monomer supplied in the mixture that is directed to the first reactor and a larger amount of the other monomer provided in the mixture that is directed to the second reactor . Advantageously, about 2: 1 to 4: 1 of the monomers are used in the feed to the first reactor and about 1: 2 to 1: 4 of the monomers in the feed for the second reactor. Other proportions may be employed when larger numbers of monomers are employed. As noted above, the amount of multimodal elastomer to be incorporated into the TPO blends of the present invention may vary from about 2 to 70% by weight of the mixture. When the final mixture includes only the polyolefin component and the multimodal elastomer, relative amounts of about 4: 6 to 5: 1 (ie, 40:60 to 80:20) would typically be employed. The polyolefin is generally present in equal or greater amounts compared to the elastomer. Minor amounts of the multimodal elastomer, ie, less than about 35 to 50% by weight, are employed when other polymer additives are included in the mixture. The addition of the multimodal elastomer provides blends that exhibit superior performance after molding and applying paint with typical flexible automotive coatings or other types of coating.
In particular, increased resistance to gasoline or other petroleum fuels has been observed. Prior to applying the paint, the molded TPO blend surfaces are pretreated with a conventional pressure wash, and a conventional chlorinated polyolefin adhesion promoter coating is employed for greater paint adhesion. Paints of all types can be used, including one-pack or two-component polyurethane coatings, which are then baked at temperatures of about 80 ° C. When superior coated performance is required after application of paint over molded TPO blends, it is advantageous to include a multimodal elastomer having a high / low molecular weight distribution. Thus, the high weight average molecular weight component will be at least about 150,000 to about 175,000 while the low weight average molecular weight component will be less than about 15,000 to 35,000. Preferably, the lowest molecular weight mode will have a density of less than 0.88, more preferably less than 0.875., and preferably even greater than 0.87 g / cc. This product preferably has a ratio between weight average molecular weight / number average molecular weight (Mw / Mn) greater than 6, more preferably greater than 8, and with special preference higher than 10 with a melt flow index § lOkg and 2 kg at 190 ° C (110/12) which is greater than 10. The ratio Mw / Mn must be greater than the difference of (110/12) - 6.63, with greater preference (110/12) - 5.63 and with special preference (110/12) - 4.63 for an optimum enhanced paint application capacity. Also, the ratio between the high molecular weight material and the low molecular weight material should be between 75:25 and 25:75 and preferably should be about 50:50. For additional advantages in terms of the strength of the welding line, impact resistance at low temperature and for an improved injection molding process capability, it is preferable to employ a multimodal elastomer, which has a high / high molecular weight distribution. . In this embodiment, a molecular weight is at least about 50,000 while the other is at least about 75,000. Preferably, a molecular weight is at least about 100,000 while the other is at least about 150,000 to 200,000. The examples illustrate the most preferred TPO mixtures of this invention. Likewise, all molecular weights are presented in weight average molecular weight unless otherwise indicated. A wide variety of additional polymer components can be added to the TPO blends of the present invention. A further polymeric component is a substantially amorphous copolymer of ethylene with a C3-C10 alpha-olefin or a terpolymer of the ethylene-alpha-olefin and a diene compound. At least two of these additional components can be used, if desired, each having a different molecular weight. Such polymeric components must have a molecular weight distribution Mw / Mn of less than about 5. Also, a substantially amorphous ethylene copolymer and an alpha-olefin, preferably propene, butene, hexene or octene, polymerized using catalysts can be employed. of metallocenes or Kaminsky and with a relatively narrow molecular weight distribution of less than about 1.8. These additional polymeric components can each be added individually in an amount of about 1 to 20% by weight. When two or more is added, the total amount of these additional components will generally be between 3 and 35% by weight. When desired, fillers can be added to the TPO blends of the present invention. Preferred fillers include inorganic materials such as talc, mica, glass, calcium carbonate or the like. The amount of filler will generally be within the range of about 2 to 30 and preferably about 3 to 15% by weight of the mixture. The TPO blends of the present invention have excellent paint application capabilities, a wide range of stiffness values, as well as high impact and tensile strengths that make these blends suitable for automotive applications. Some blends also show superior weld line strength, low temperature resistance and improved process capability during injection molding. The TPO blends of the present invention can be molded or otherwise formed to produce lightweight, durable articles, and having suitable surfaces for receiving paint. The articles can be treated with an adhesion promoter and then painted, and the paint can be cured at temperatures above 80 ° C in order to produce a durable and attractive finish. Any of the conventional adhesion producers can be used with good results. The polymer blends of the present invention can be coated with paints, particularly with paints such as commercially available two-component polyurethanes, to offer products with superior resistance to fluids and oil. The mixtures of the present invention may also be coated with paints having active functional groups such as epoxy resins, polyesters, acrylics, carbodiimides, urea resins, menamine-formaldehyde resins, enamines, keto-imines, amines, and isocyanates for offer products with improved resistance to fluids. These types of paints are well known in the paints and coatings industry. Various additives can be incorporated into the polymer blends of the present invention in order to vary the physical properties of the blends of the present invention while maintaining good paint adhesion. These additives may include pigments, colorants, processing aids, antistatic additives, surfactants, and stabilizers such as those generally employed in polymer compositions. Other conventional additives, such as for example nucleating agents, oils, lubricants, antioxidants, UV stabilizers, fungicides, bacteriocides, and the like may be included if desired. Particularly useful additives may influence styrene-maleic anhydride copolymers and cationic surfactants to improve moisture resistance, as well as well-known copolymers such as ethylene-acrylic acid copolymers ("EAA") and ethylene-methacrylic acid copolymers ("EMAA"). »), Or mixtures thereof. The resistance to fluids of preformed objects of the polymer blends of the present invention carrying a single commercially available 2-component polyurethane coating is evaluated by placing the coated preformed objects in a gasoline bath. The fuel bath can be mixtures of any of the following: 90% unleaded gasoline and 10% ethanol; 90% unleaded gasoline and 10% methanol; or 100% unleaded gasoline. The preformed objects used are 2.5-inch squares or possibly one-inch by three-inch bars. The coated preformed objects remain immersed in the gasoline bath until the failure, that is, until the paint on the edges of the preformed objects detaches from the preformed objects. The coated preformed object is then removed from the bath and the time to failure is recorded. The resistance to fluids of the coated preformed objects is shown in the examples. The percentage of area that presents a detachment of the paint from the preformed object is a measure also of the ability of the preformed object to preserve the paint against the action of petroleum fluids such as gasoline. The preformed painted object is removed from the gas bath after a 30 minute immersion period and the area eventually free of paint is measured. The percentage of area exhibiting paint detachment is determined by dividing the area of the preformed object without paint between the original painted area of the preformed object. It is desired to obtain a percentage area with low paint detachment. EXAMPLES The present invention will be described below with reference to the following non-limiting examples. The mixtures of the examples are formed by mixing the components in the indicated amounts. The mixture of the components is carried out by well-known methods and devices such as Banbury mixers and extrusion equipment. Polymer blends can be molded into preformed objects by known methods such as extrusion, injection molding, blow molding, or thermoforming. The preformed articles of the polymer blends are coated with a single layer of two-component polyurethane paint according to well-known methods, such as spray application. Polymer blends can also be formed into pellets for storage and shipping prior to molding in the articles formed. Generally, the processing of the polymer blends of the present invention can be carried out using Banbury mixers or twin screw extruders. When a Banbury mixer is used to prepare these mixtures, a single screw extruder can be used to form the pellet component mixture. The resulting pellets are then supplied to an injection molding machine for the manufacture of molded articles. During the preparation of these mixes with a Banbury mixer, the tamping pressure in the Banbury mixer is approximately 30 to 35 psi. The mixing continues until the melting temperature is reached, ie the temperature at which the viscosity of the mixture drops strongly. When the melting temperature is reached, the mixture ends and the resulting batch of material is removed from the Banbury mixer. The batch is then ground into flakes and / or pelletized in a single screw extruder. The pellets of the mixtures formed of components are supplied to an injection molding machine to form the products through injection molding. The processing conditions are presented below in Table 1. Table 1 PROCESSING CONDITIONS Banbury Mixing Rotor Speed (RPM) 185 Tamping Pressure (PSI) 32 Time to Melt (SEC) 95 Melting Temperature (° F) 360 Temperature batch (° F) 410 UNIQUE SCREW EXTRUDER FOR PELLET FORMATION Extreme zone temperature (° F) 360 Central zone temperature (° F) 380 Screw speed (RPM) 95 Fusing temperature (° F) 375 TEMPERATURE MOLDING End area 1 340 Center area 2 360 Center area 3 360 End area 4 340 Screw speed (RPM) 90 Mold temperature (° F) 80 Injection time (SEC) 10 Cooling time (SEC) 25 Pressure Injection (PSI) 550 Filling time (PSI) 10 Retention pressure (PSI) 430 Retention time (SEC) 15 Contra pressure (PSI) 50 The bimodal elastomers are manufactured in accordance with the above described, with the information offered in the examples as an accurate formulation of these materials. Examples 1 to 8 Table 2 shows useful mixtures together with properties such as for example gasoline resistance, melt flow rate and density. In these examples, the surfaces of the articles to be painted are conventionally pressure washed and treated with a conventional chlorinated polyolefin adhesion promoter. A 2-component polyurethane coating is then applied and cured by baking at a temperature of about 80 ° C. Table 2 Type of material Form Class Cl C-2 C-3 C-4 Ejl 20mfr PP Flakes 65 65 65 65 65 EPDM I Paca 14 14 14 14 EO 1 Pellets 21 EO 2 Pellas 35 21 T-56-DCPD liquid EPDM 300 -1 Pellets EOBM 21 C01R02 Pellets EOBM 21 C01R02A Pellets EOBM C01R03 Pellets EOBM C01R05 Pellets EOBM C18R3 Pellets EOBM B225 Pellets AO 0.3 0.3 0.3 0.3 0.3 Property Units E-10 x. Min. 10 26 10 20 > 120 WB130CDI / R784 / R788 dg / min. 9.4 9.4 10.2 16.2 13.9 MFR, 23 ° C / 2.16Kg Type of material Form Class Ej5 Ex6 Ex7 Ex8 20mfr PP Flakes 65 65 65 65 EPDM I PPaaccaa 19.1 19.1 EO 1 PPeellllaass 154.4 EO 2 Pellas T-56-DCPD liquid EPDM 300-1 Pellets EOBM C01R02 Pellas EOBM C01R02A Pellets EOBM C01R03 Pellets EOBM C01R04 Pellets EOBM 15.9 C01R05 Pellets EOBM 15.9 C18R3 Pellets EEOOBBMM 3355 19.6 B225 Pellas A AOO 00..33 00..33 00..33 0.3 Property Uni Lddaaddeess E-10 x. M Miinn .. > > 112200 > > 112200 > > 6600 41 WB130CDI / R784 / R788 MFR, 23 ° C / 2.16Kg dg / min. 12.1 13.9 17.1 15.3 NOTES: 20mfr PP: Polypropylene, Melt flow rate = 20 dg / min @ 230 ° C / 2.61 Kg available in EPDM I: 4% ethylidene norbornene, C2 / C3 = 58/42, Mooney = ML (l + 4) §100 ° C available in EO 1: Ethylene-octene copolymer, 0.5 MI @ 190 ° C / 2.61 kg; Mw / Mv = 2.0 110/12 = 8.1 available in EO 2: Ethylene-octene copolymer, 0.5 MI @ 190 ° C / 2.61Kg; Mw / Mn = 2.1 110/12 = 7.3 available in T-56-DCPD: 9.5% EPDM Dicyclopentadiene, C2 / C3 = 48/52, Mv = 5,500, available in 300-1: approximately 36% by weight of 4K Mw 0.886 g / cc, approximately 645 by weight of 158K Mw 0.862 g / cc, Overall Mw = 102K, 0.868 g / cc; Mw / Mn = 23 C01R02: approximately 51% by weight of 12.7K Mw 0.87 g / cc, approximately 49 by weight of 227K Mw 0.857 g / cc, Overall Mw = 118K, 0.863 g / cc; Mw / Mn = ll C01R02A: approximately 56% by weight of 14.5K Mw 0.87 g / cc, approximately 44 by weight of 247K Mw 0.858 g / cc, Overall Mw = 116K, 0.864 g / cc; Mw / Mn = ll C01R03: approximately 50% by weight of 9K Mw 0.877 g / cc, approximately 50 by weight of 215K Mw 0.861 g / cc, Global Mw = lllK, 0.867 g / cc; Mw / Global Mn = 14, 110/12 = 17 C01R04: approximately 44% by weight of 7.1K Mw 0.877 g / cc, approximately 56 by weight of 217K Mw 0.865 g / cc, Overall Mw = 125K, 0.871 g / cc; Mw / Global Mn = 21, 110/12 = 12 C01R05: approximately 44% by weight of 5.7K Mw 0.874 g / cc, approximately 56 by weight of 214K Mw 0.865 g / cc, Overall Mw = 122K, 0.87 g / cc; Mw / Global Mn = 21, 110/12 = 14 As can be seen from the comparison of controls 1 to 4 with examples 1 and 2, the use of bimodal elastomer according to the present invention offers flow rates of higher melting of the Tpo blend, as well as a significant increase in gasoline resistance of up to 5 times what is seen with comparison examples for painted molded articles of such blends. Control 4 shows that the low molecular weight mode should have a density less than 0.88 g / cc to achieve good paint adhesion. A comparison of control 5 with examples 1 to 6 illustrates the excellent paint adhesion that can be obtained without having to use a low molecular weight, liquid EPDM. Examples 3 to 6 illustrate the example on the melt viscosity by varying the relative amounts of high molecular weight EPDM and bimodal elastomer. These examples also show that the use of different molecular weight distributions in the bimodal elastomer within the ranges illustrated does not significantly affect the performance of the blend of its beneficial paint adhesion properties. Examples 9 and 10 These examples illustrate the comparative properties and performance of TPO blends containing a high / high bimodal elastomer with different conventional formulations containing poly (ethylene-alpha-butene or co-octene) elastomers, the formulations and properties are illustrated in Table 3. A comparison of Control 7 and Example 9 shows that the use of the bimodal elastomer offers much better weld line strength than the use of the poly (ethylene-octene) elastomer. Example 10 compared to controls 8 to 11 shows that the use of the bimodal elastomer offers much better weld line strengths and better properties of low temperature impact resistance compared to blends containing poly (ethylene) elastomers. -buteno or -octeno). further, the gloss of the painted article of example 10 which included the bimodal elastomer, improved significantly compared to the brightness of control 8, which included a mixture of poly (ethylene-butene and -octene) elastomers. TABLE 3 Material Type C-7 Ej9 C-8 C-9 20 MFR PP 60 60 35 MFR HIPP 62 62 EBR 22 E0R1 11 E0R2 40 EOR3 33 EOR Bimodal 40 Filler Property Izod § Temperature Environment PB PB (feet-pound / inch ) Izod §-10 ° C 1.26 PB (feet-pounds / inch) Izod @ -30 ° C 1.44 1.43 (feet-pounds / inch) WL peak strength at 2854 3169 3567 3919 Friction (psi) WL In from flex to break 2.85 3.01 0.74 1.08 (inch-pound) WL tensile strength 1930 2042 2349 2019 To break (psi) WL elongation to break 8 11.1 3.2 2.7 By tension (%) WL In to break by. 15.4 22.9 6.3 4.4 Tension (inch-pound) Brightness 68.8 Type of Material C-10 C-ll EjlO 20 MFR PP 35 MFR HIPP 62 62 62 EBR EOR1 EOR2 33 23 E0R3 10 EOR Bimodal 33 Filler 5 Property Izod § Temperature Ambient NB NB NB (feet-pound / inch) Izod @ -10 ° C 3.09 PB PB (ft-lbs / inch) Izod § -30 ° C 1.49 1.68 2.39 (ft-lbs / inch) WL peak strength at 3413 3774 4253 Friction (psi) WL In flex to break 0.67 0.89 3.03 ( inch-pound) WL tensile strength 1855 2059 2567 At break (psi) WL elongation at break 2.4 2.8 4.3 For tension (%) WL At breakage by 3.6 4.7 10.2 Voltage (inch-pound) Brightness 62.6 Notes: 20 MFR PP : Polypropylene, Melt flow rate = 20 dg / min @ 230 ° C / 2.16 Kg available in Solvay as 35 MFR HIPP: Polypropylene, Melt flow rate = 35 dg / min @ 230 ° C / 2.16 Kg available in Solvay as EBR: Poly (ethylene-co-butene), C2 = 80%, MFR§190 ° C, 2.16 Kg = 0.8 dg / min E0R1: Poly (ethylene-co-octene); C2 = 80%, MFR @ 190 ° C, 2.16 Kg = 5 dg / min EOR2: Poly (ethylene-co-octene); C2 = 80%, MFR §190 ° C, 2.16 Kg = l dg / min EOR3: Poly (ethylene-co-octene); C2 = 80%, MFR §190 ° C, 2.16 Kg = 0.5 dg / min Bimodal EOR: Poly (ethylene-co-octene); MW of high mode = 260,000; MW low mode = 114,000 Izod test: NB = no break; PB = partial rupture; WL = welding line When reviewing the data, it is observed that in the first mode the best results are obtained when a multimodal elastomer having high and low molecular weight components offers an increased paint bond to the molded polymer mixture. In the second embodiment, better physical properties are obtained, particularly welding line strength and impact resistance at low temperature compared to mixtures that do not contain the multimodal elastomers. Other aspects of the present invention will be apparent to those skilled in the art taking into account the specification or from the practice of the invention presented herein. For example, despite the fact that the preferred embodiment of the present invention includes a bimodal elastomer, a person with certain knowledge in the field will observe that multimodal elastomers with 3, 4, 5 or even more modes can be provided by making the elastomer in multiple reactors sequentially arranged in accordance with the principles presented here for two reactors. Such multimodal elastomers are considered part of the present invention since they contain at least two modes of compliance with what is specifically presented herein. Thus, the specification and the examples should be considered for illustrative purposes only, and the scope and spirit of the present invention are indicated in the following claims.

Claims (24)

  1. CLAIMS.
  2. A thermoplastic polyolefin blend comprising: a polyolefin component of a substantially crystalline polymer in an amount of about 30 to 98% by weight of the mixture; and a sequentially polymerized ethylene-alpha-olefin copolymer elastomer having a multimodal distribution of at least one of the alpha-olefin molecular weight, density or monomers, and is present in an amount of about 2 to 70% by weight. weight of the mixture.
  3. The mixture of claim 1, wherein the polyolefin is present in an amount of about 50 to 95% by weight of the mixture, and it is a polyethylene polymer, "polypropylene polymer or crystalline or semi-crystalline ethylene copolymer and at least one alpha-olefin c3 a cio" The mixture of claim 1, wherein the multimodal elastomer is substantially amorphous and is present in an amount of about 4 to 60% by weight.
  4. The mixture of claim 3, wherein the multimodal elastomer has at least two weight average molecular weight modes differing by at least about 25,000.
  5. The mixture of claim 4, wherein one mode has a weight average molecular weight that is a multiple of at least 1.5 to about 50 times the weight average molecular weight of the other mode.
  6. The mixture of claim 5 wherein the molecular weight of one mode is about 30,000 or less and the molecular weight of the other mode is at least about 150,000.
  7. The mixture of claim 6, wherein the lower molecular weight mode has a density less than about 0.88 g / cc.
  8. The mixture of claim 4, wherein the molecular weight of one mode is at least about 75,000 and the molecular weight of the other mode is at least about 115,000.
  9. The mixture of claim 4, wherein the molecular weight of one mode is about 100,000 and the molecular weight of the other mode is at least about 200,000.
  10. The mixture of claim 3, wherein the multimodal elastomer has at least two density modes differing by at least about 0.005 g / cc.
  11. The mixture of claim 10, wherein the multimodal elastomer has a density mode of at least 0.85 g / cc and the other density mode less than about 0.96 g / cc, with the difference between the densities of higher and lower mode less than about 0.1 g / cc.
  12. The mixture of claim 3, wherein the multimodal elastomer has at least two modes including comonomers that differ in length by at least one carbon atom.
  13. The mixture of claim 3, wherein the multimodal elastomer has at least two modes wherein the comonomers differ in length by at least two carbon atoms, and one of which is propene, butene, hexene or octene.
  14. The mixture of claim 1, further comprising at least one additional polymer component in an amount comprised between about 1 and 20% by weight of the mixture.
  15. 15. The mixture of claim 1, wherein at least two different additional polymeric components are present but in a total amount of about 3 and 35% by weight of the mixture.
  16. 16. The mixture of claim 15, wherein a further polymer component is copolymers of ethylene and a C3 alpha-olefin to CIO or a terpolymer of ethylene and a C3 alpha-olefin to CIO and a diene monomer, and another polymeric component further is a copolymer of ethylene and an alpha-olefin made with a metallocene or Kaminsky catalyst.
  17. 17. The mixture of claim 1, further comprising a filler in an amount of about 1 to 30% by weight of the mixture.
  18. 18. The mixture of claim 17, wherein the filler is talc, mica, glass or calcium carbonate.
  19. 19. The mixture of claim 1, in the form of a molded article having an external surface, a total molecular weight comprised between 70, 000 and 300,000, and a global density between 0.85 and 0.95 g / cc.
  20. 20. The mixture of claim 17 in the form of a molded article having an external surface, a total molecular weight of between 70,000 and 300,000, and an overall density of between 0.85 and 1.25 g / cc.
  21. 21. The mixture of claim 19, wherein at least a portion of the external surface of the article includes a coating.
  22. 22. The mixture of claim 20, wherein at least a portion of the external surface of the article includes a coating.
  23. 23. The mixture of claim 21, wherein the coating comprises a two component polyurethane material.
  24. 24. The mixture of claim 22, wherein the coating comprises a two component polyurethane material.
MXPA/A/1999/004317A 1996-11-08 1999-05-10 Tpo blends containing multimodal elastomers MXPA99004317A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US08747124 1996-11-08

Publications (1)

Publication Number Publication Date
MXPA99004317A true MXPA99004317A (en) 2000-05-01

Family

ID=

Similar Documents

Publication Publication Date Title
AU729522B2 (en) TPO blends containing multimodal elastomers
EP1187876B1 (en) Injection moulding
KR100649809B1 (en) Polyolefin composition with improved impact properties
US5783629A (en) Thermoplastic polyolefins having improved paintability properties
JP5118030B2 (en) Filler-containing TPO compositions, methods for their production and articles made therefrom
CN100519600C (en) Polyolefin with improved scratch resistance and process for producing the same
CA2410486C (en) Polyolefin materials having enhanced surface durability
CN105073875B (en) Coated product
AU735217B2 (en) Thermoplastic olefin composition with a good adhesion/ durability balance
US20040249080A1 (en) Soft touch polyolefin compositions
US6166132A (en) Directly paintable thermoplastic olefin composition containing maleic anhydride-modified polymers
CN1176987C (en) Polyolefin compsns. having improved low temp toughness and methods therefor
MXPA99004317A (en) Tpo blends containing multimodal elastomers
US20050107560A1 (en) Injection molded articles
JP2009173904A (en) Polypropylene resin composition and blow-molded article comprising the same
JPS61185546A (en) Olefin polymer composition
JP2002088164A (en) Molded product of olefinic thermoplastic elastomer, method for producing the same and use thereof
JPH04309543A (en) Low-density polythylene resin composition
MXPA99004014A (en) Impact-modified thermoplastic polyolefins and articles fabricated therefrom
MXPA00004960A (en) Modification of thermoplastic vulcanizates with a thermoplastic random copolymer of ethylene
SK16198A3 (en) Termoplastic olefinic composition and injection molded article containing the same
MXPA98001332A (en) Composition of olefins, thermoplastic, directly pintable, containing polymers modified with male anhydride