Poly-ethylene-propylene rubber

Other authors have used different polymers with backbones such as poly(ethylene-propylene) rubbers or polyethylene oxide) grafted or interpenetrated with poly (acrylic acid), poly(methacrylic acid), poly(p-vinyl pyridine), or poly (vinyl alcohol) (237). The immobilization protocol was not... 

Poly(propylene) + poly(ethylene-propylene) rubber Fractional precipitation 1,2,4-Trichlorobenzene TREF... 

The use of ABS has in recent years met considerable competition on two fronts, particularly in automotive applications. For lower cost applications, where demands of finish and heat resistance are not too severe, blends of polypropylene and ethylene-propylene rubbers have found application (see Chapters 11 and 31). On the other hand, where enhanced heat resistance and surface hardness are required in conjunction with excellent impact properties, polycarbonate-ABS alloys (see Section 20.8) have found many applications. These materials have also replaced ABS in a number of electrical fittings and housings for business and domestic applications. Where improved heat distortion temperature and good electrical insulation properties (including tracking resistance) are important, then ABS may be replaced by poly(butylene terephthalate). 

EPR Ethylene-propylene rubber NR Natural rubber poly isoprene... 

Figure 14.9 Effect of various impact modifiers (25wt%) on the notched Izod impact strength of recycled PET (as moulded and annealed at 150°C for 16 h) E-GMA, glycidyl-methacrylate-functionalized ethylene copolymer E-EA-GMA, ethylene-ethyl acrylate-glycidyl methacrylate (72/20/8) terpolymer E-EA, ethylene-ethyl acrylate EPR, ethylene propylene rubber MA-GPR, maleic anhydride grafted ethylene propylene rubber MBS, poly(methyl methacrylate)-g-poly(butadiene/styrene) BuA-C/S, poly(butyl acrylate-g-poly(methyl methacrylate) core/shell rubber. Data taken from Akkapeddi etal. [26]...

Ethylene-propylene-diene rubber Poly(ethylene-propylene-diene)... 

Rigid impact poly (vinyl chloride) can be made either by polyblending or by grafting. P. Dreyfuss, M. P. Dreyfuss, and H. A. Tucker, discuss in their chapter polyblends of poly (vinyl chloride) with polyethers. F. Wollrab, F. Declerck, J. Dumoulin, M. Obsomer, and P. Georlette review grafting of vinyl chloride upon polyethylene, ethylene/ propylene rubber, and chlorohydrin rubber. 

ABA ABS ABS-PC ABS-PVC ACM ACS AES AMMA AN APET APP ASA BR BS CA CAB CAP CN CP CPE CPET CPP CPVC CR CTA DAM DAP DMT ECTFE EEA EMA EMAA EMAC EMPP EnBA EP EPM ESI EVA(C) EVOH FEP HDI HDPE HIPS HMDI IPI LDPE LLDPE MBS Acrylonitrile-butadiene-acrylate Acrylonitrile-butadiene-styrene copolymer Acrylonitrile-butadiene-styrene-polycarbonate alloy Acrylonitrile-butadiene-styrene-poly(vinyl chloride) alloy Acrylic acid ester rubber Acrylonitrile-chlorinated pe-styrene Acrylonitrile-ethylene-propylene-styrene Acrylonitrile-methyl methacrylate Acrylonitrile Amorphous polyethylene terephthalate Atactic polypropylene Acrylic-styrene-acrylonitrile Butadiene rubber Butadiene styrene rubber Cellulose acetate Cellulose acetate-butyrate Cellulose acetate-propionate Cellulose nitrate Cellulose propionate Chlorinated polyethylene Crystalline polyethylene terephthalate Cast polypropylene Chlorinated polyvinyl chloride Chloroprene rubber Cellulose triacetate Diallyl maleate Diallyl phthalate Terephthalic acid, dimethyl ester Ethylene-chlorotrifluoroethylene copolymer Ethylene-ethyl acrylate Ethylene-methyl acrylate Ethylene methacrylic acid Ethylene-methyl acrylate copolymer Elastomer modified polypropylene Ethylene normal butyl acrylate Epoxy resin, also ethylene-propylene Ethylene-propylene rubber Ethylene-styrene copolymers Polyethylene-vinyl acetate Polyethylene-vinyl alcohol copolymers Fluorinated ethylene-propylene copolymers Hexamethylene diisocyanate High-density polyethylene High-impact polystyrene Diisocyanato dicyclohexylmethane Isophorone diisocyanate Low-density polyethylene Linear low-density polyethylene Methacrylate-butadiene-styrene... 

On the other hand, some mechanically compatible blends as well as some dispersed two-phase systems have made respectable inroads into the commercial scene. Many of these are blends of low-impact resins with high-impact elastomeric polymers examples are polystyrene/rubber, poly (styrene-co-acrylonitrile) /rubber, poly (methyl methacrylate) /rubber, poly (ethylene propylene)/propylene rubber, and bis-A polycarbonate/ ABS as well as blends of polyvinyl chloride with ABS or PMMA or chlorinated polyethylene. 

FIG. 18.3 Activation energy of diffusion as a function of Tg for 21 different polymers from low to high temperatures, ( ) odd numbers (O) even numbers 1. Silicone rubber 2. Butadiene rubber 3. Hydropol (hydrogenated polybutadiene = amorphous polyethylene) 4. Styrene/butadiene rubber 5. Natural rubber 6. Butadiene/acrylonitrile rubber (80/20) 7. Butyl rubber 8. Ethylene/propylene rubber 9. Chloro-prene rubber (neoprene) 10. Poly(oxy methylene) 11. Butadiene/acrylonitrile rubber (60/40) 12. Polypropylene 13. Methyl rubber 14. Poly(viny[ acetate) 15. Nylon-11 16. Poly(ethyl methacrylate) 17. Polyethylene terephthalate) 18. Poly(vinyl chloride) 19. Polystyrene 20. Poly (bisphenol A carbonate) 21. Poly(2,6 dimethyl-p.phenylene oxide). 

Also compatibilizers can be applied for two-phase systems in order to reduce the phase size and improve the properties. This method has been successfully applied in an EPDM-silicone system using a silane grafted ethylene-propylene rubber (EPR) [5]. However, the combination possibilities of poly(organosiloxane)s with thermoplastics and elastomers are still limited to special systems. 

Ethylene-propylene rubber Poly(ethylene-propylene) -h-(CH2— CH2)j-eCH2—CH>-] CH3... 

Blends of poly(3-hydroxyalkanoic acid)s (PHAs) with various natural and synthetic polymers have been reported as reviewed in Refs. [21,22]. By blending with synthetic polymers it is expected to control the biodegradability, to improve several properties, and to reduce the production cost of bacterially synthesized PHAs. The polymers investigated as the blending partners of PHAs include poly(ethylene oxide) [92, 93], poly(vinyl acetate) [94], poly(vinylidene fluoride) [95], ethylene propylene rubber [94, 96], po-ly(epichlorohydrin) [97, 98], poly(e-caprolactone) [99], aliphatic copolyesters of adipic acid/ethylene glycole/lactic acid [100] and of e-caprolactone/lactide... 

In this section, the future developments will be discussed that might be expected in commercial polymer blends comprising at least one of the constituents from the class of commodity polymers. Generally, the commodity polymers considered include polyethylene (and variants LDPE, HOPE, LLDPE, VLDPE and ethylene copolymers), polypropylene (PP), ethylene-propylene rubber (EPR and EPDM), polyvinylchloride (PVC), polystyrene (PS), ABS, and poly(methyl methacrylate) (PMMA). Elastomeric polymers commonly used in tire and associated applications are important in polymer blends as many tire component constructions employ polymer blends to maximize performance. However, these will not be considered here. Thermosetting polymers which could be classified as commodity polymers (urethane, phenolics, epoxies) will also not be covered, but will be mentioned in a later section discussing new polymer blends designed for specific applications (e.g., water based coatings). 

The choice of date range is arbitrary. The number of journal articles for each year was obtained from a search of electronic version of English-based polymer and polymer-related journals using the keywords polyolefin and blends. Within polyolefin keyword, the subkeywords used in the search were polyethylene (PE, LLDPE, LDPE, HDPE, UHMWPE, PE, etc.), polypropylene (PP, iPP, sPP, aPP, etc.), polybutene-1, poly-4-methylpentene-l, ethylene-diene monomer, ethylene-propylene-diene terpolymer, ethylene propylene rubber, thermoplastic olefins, natural rubber (NR), polybutadiene, polyisobutylene (PIB), polyisoprene, and polyolefin elastomer. For the polyolefin blends patent search, polymer indexing codes and manual codes were used to search for the patents in Derwent World Patent Index based on the above keywords listed in the search strategy. 

As discussed earlier, ethylene propylene rubber (EPR or EPM) has been blended with PP and PE to improve the impact strength and to render the materials softer. Recently, metallocene catalysts or postmetallocene catalysts provide new pathways to generate elastic copolymers that can replace EPR. These pathways possess cheaper manufacturing cost and generate new materials with better compatibility to PP or PE. Such new materials included ethylene-propylene random copolymers with dominant ethylene component (33-34) or propylene-dominant component (35 1), propylene-ethylene block copolymer (42), ethylene-octene copolymer (43), poly(propylene-co-ethylene) (44), ethylene-hexene copolymer (45), ethylene-butene copolymer (46), low isotactic PP (47), and stereoblock PP (48). These materials are generally compatible with PP or PE, thus can be used to tailor the toughness (or the softness) of... 

High density polyethylene (HOPE) Linear low density polyethylene (LLDPE) Isotactic polypropylene (iPP) Syndiotactic polypropylene (sPP) tram-1,4-Polyisoprene Syndiotactic polystyrene (sPS) Cyclooleflns Ethylene-propylene copolymers Styrene-ethylene copolymers cw -1,4-polybutadiene rrarw -1,4-Poly isoprene Random ethylene-a-olefin copolymers Ethylene-propylene rubber (EPR) Ethylene-propylene-diene copolymers (EPDM)... 

The early synthetic rubbers were diene polymers such as poly butadiene. Diene elastomers possess a considerable degree of unsaturation, some of which provide the sites required for the light amount of cross-linking structurally necessary for elastomeric properties. The residual double bonds make diene elastomers vulnerable to oxidative and ozone attack. To overcome this problem, saturated elastomers like butyl rubber and ethylene-propylene rubber (EPR) were developed. These rubbers were, unfortunately, not readily vulcanized by conventional means. To enhance cure, it was therefore necessary to... 

Peroxides are vulcanizing agents for elastomers, which contain no sites for attack by other types of vulcanizing agents. They are useful for ethylene-propylene rubber (EPR), ethylene-vinyl acetate copolymers (EAM), certain millable urethane rubbers, and silicone mbbers. They generally are not useful for vulcanizing butyl rubber (poly[isobutylene-co-isoprene]) because of a tendency toward chain scission, rather than crosslinking, when the polymer is subjected to the action of peroxide. 

Cross-linking by addition polymerization is also used to a considerable extent. Unsaturated polyesters are cross-linked by copolymerization with styrene or methyl methacrylate. Cross-linking soft, natural rubber with sulfur gives the normally used hard, vulcanized rubber. Ethylene-propylene rubbers can be cross-linked with peroxides. The cross-linking of elastomers is also called vulcanization, since the classic cross-linking of natural rubber, cis-l,4-poly(isoprene), uses heat and sulfur, which were the elements assigned to the god Vulcan (see also Chapter 37). 

All diene rubbers discussed so far, natural rubber, styrene-butadiene rubbers, poly-butadienes), butyl rubbers, and ethylene-propylene rubbers, consist of aliphatic or aromatic monomeric units. They swell readily in aliphatics they have poor oil resistance. But the free radical copolymerization of acrylonitrile with butadiene leads to what is known as nitrile rubber, which has good oil resistance because of the many polar nitrile groups. However, the rebound elasticity and the low-temperature flexibility decrease with increasing nitrile fraction. Consequently, NBR is mainly used for fuel hoses, motor gaskets, transport belts, etc. 

Numerous nylon blends prepared by compatibilization or reactive blending are commercially successful. The modifiers fiequenfly utilized in commercial nylon blends include polyolefin, thermoplastic polyolefin, thermoplastic polyunethane, ionomer, elastomer, ethylene-propylene rubber, nitrile mbber, polyftetrafluoroethylene), poly (phenylene ether), poly(ether amide), silicone, glass fiber, and carbon fiber. The nonpolar modifiers such as polyolefin, maleic anhydride or a polar vinyl monomer such as acrylic acid, methaciylic acid and fimiaric acid is fiequently incorporated to introduce reactive sites in nylon. 

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