Poly ethylene-propylene copolymer

FEP film pLUORINE COMPOUNDS, ORGANIC - PERFLUORINATED ETHYLENE-PROPYLENE COPOLYMERS] (Vol 11) -P7E film for pLUORINE COMPOUNDS, ORGANIC - POLY(7UNYL FLUORIDE)] (7E111)... 

Perfluorinated ethylene—propylene copolymers, Tetrafluoroethylene—ethylene copolymers, Tetrafluoroethylene—perfluorovinyl ether copolymers, Poly(vinyl fluoride),... 

FIGURE 5.17 Temperature versus G —the shear storage modulus at a frequency of 1.6 Hz for diblock copolymer poly(ethylene propylene)-poly(ethylethylene) (PEP-PEE). The order-disorder transition (ODT) calculated to be 291°C 1°C. (From Rosedale, J.H. and Bates, F.S., Macromolecules, 23, 2329, 1990. With permission of American Chemical Society.)... 

In studies of networks of polybutadiene (18) and an ethylene-propylene copolymer (13), h was found to be essentially zero, though for various poly(dimethylsiloxane) (PDMS) networks, h has been found (19) to be greater than zero. Nevertheless, without further justification, h will here be equated to zero. Equation 2 now becomes... 

For example, a PE-fe-poly(ethylene-co-propylene) diblock composed of crystalline PE and amorphous ethylene/propylene copolymer segments was synthesized from ethylene and ethylene/propylene. The addition of MAO and Ti-FI catalyst 40 (Fig. 25) to an ethylene-saturated toluene at 25 °C resulted in the rapid formation of a living PE (Mn 115,000, MJMn 1.10). The addition of ethylene/propylene (1 3 volume ratio) to this living PE formed a PE-/>poly(ethylcnc-co-propylcnc) block copolymer (Mn 211,000, MJMn 1.16, propylene content 6.4 mol%) [30], As expected, the polymer exhibits a high Tm of 123 °C, indicating that this block copolymer shows good elastic properties at much higher temperatures than the conventional random copolymers of similar densities. 

Only a few publications deal with ABC triblock copolymers where two of the blocks are able to crystallize. The systems that have been investigated include PS-b-PE-b-PCL [94,98], PE-b-PS-6-PCL [94], PS-fc-PEO-fo-PCL [30,134-136] and PE-fo-poly(ethylene-propylene)-fr-PEO [101,119] (see also Table 1). 

Alexandridis P, Athanassiou V, Eukuda S, Hatton TA. Surface activity of polyfethylene oxide)-f>tock-poly(propylene oxide)-f>tock-poly(ethylene oxide) copolymers. Langmuir 1994 10 2604-2612. 

Films made from TPX exhibit an insufficient heat sealability. A widely adopted solution for improving such insufficient heat sealability is addition of a low density poly(ethylene) (LDPE) homopolymer or an ethylene propylene copolymer. However, the addition of these polymers only result in little improvement in their heat sealability. Instead, the addition results in poor dispersion and deteriorated impact resistance (23). 

Screening tests were conducted on potential construction materials. The candidate materials evaluated included the following polytetrafluoroethylene (PTFE, TFE), fluorinated ethylene-propylene copolymer (FEP), perfluoroalkoxy-alkanes (PFA), ethylene-tetrafluoroethylene copolymer (ETFE), ethylene-chlorotrifluoroethylene copolymer (E-CTFE), poly vinylidene fluoride (PVDF), polypropylene (PP), and polyvinyl chloride (PVC). These materials were chosen based on cost, availability, and information from manufacturers on compatibility with acid solutions. 

Similarly, the random introduction by copolymerization of sterically incompatible repeating unit B into chains of crystalline A reduces the crystalline melting point and degree of crystallinity. If Tm is reduced to T, crystals cannot form. Isotactic polypropylene and linear polyethylene homopolymers are each highly crystalline plastics. However, a random 65% ethylene—35% propylene copolymer of the two, poly(ethylene-L -prop iene) is a completely amorphous ethylene—propylene mbber (EPR). On the other hand, block copolymers of the two, poly (ethylene- -propylene) of the same overall composition, are highly crystalline. X-ray studies of these materials reveal both the polyethylene lattice and the isotactic polypropylene lattice, as the different blocks crystallize in their own lattices. 

The mechanical and thermal properties of a range of poly(ethylene)/ poly(ethylene-propylene) (PE/PEP) copolymers have been examined by Mohajer et al. (1982). They studied the effect of variation of composition and copolymer architecture on the polymer properties by synthesizing a range of PE-PEP-PE and PEP-PE-PEP triblocks and PE-PF.P diblocks with high molecular weights (M > 200 kg mol (.The crystallinity, density and melting enthalpy for all copolymers were found to be linearly dependent on the PE content, indicating microphase separation of PE and rubbery PEP in the solid state. The... 

All these elastomers, especially poly thylene-fo-butylene) and poly(ethylene- -propylene), are nonpolar. The corresponding block copolymers can thus be compounded with hydrocarbon-based extending oils, but do not have much oil resistance. Conversely, block copolymers with polar polyester or polyether elastomer segments have litde affinity for such hydrocarbon oils and so have better oil resistance. 

Materials. Ethylene-propylene copolymer, purified by Kumagawa (9) acetone extraction for 180 hours had a composition (determined by infrared) of C2 — 54.5, C3 = 45.5 wt %, and an intrinsic viscosity determined in toluene at 30°C of 1.38 X 10 cc/gram. Poly (vinyl alcohol) was Elvanol 50-42 from du Pont. The vinyl chloride monomer of Monte-catini Edison was 99.99% pure. Initiators used were ... 

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... 

The Ziegler-Natta catalysts have acquired practical importance particularly as heterogeneous systems, mostly owing to the commercial production of linear high- and low-density polyethylenes and isotactic polypropylene. Elastomers based on ethylene-propylene copolymers (with the use of vanadium-based catalysts) as well as 1,4-cz s-and 1,4-tran.y-poly(l, 3-butadiene) and polyisoprene are also produced. These catalysts are extremely versatile and can be used in many other polymerisations of various hydrocarbon monomers, leading very often to polymers of different stereoregularity. In 1963, both Ziegler and Natta were awarded the Nobel Prize in chemistry. 

Note ETFE, copolymer of ethylene and tetrafluoroethylene MFA, copolymer of perfluoromethylvi-nylether and tetrafluorethylene PFA, copolymer of perfluoropropylvinylether and tetrafluoroethylene FEP, fluorinated ethylene-propylene copolymer PCTFE, poly(chlorotrifluoroethylene) PVDF, poly(vinylidene fluoride) VDF-HFP, copolymer of vinylidene fluoride and hexafluoropropylene. 

Substrate materials included poly (dimethyl siloxane) (SR) (Silastic Rubber, medical grade, Dow Corning), fluorinated ethylene/propylene copolymer (FEP) (Teflon FEP, Dupont), and a segmented copolyether-urethane-urea (PEUU) based on poly (propylene glycol), methylene bis-4-phenylisocyanate, and ethylenediamine. This PEUU was provided by D. J. Lyman. 

A net adsorption value (corrected for any IRS prism contamination) which could be related to calibration curves for surface concentration was obtained from the ratio of the amide I (C=0 stretching) band at 1640 cm to a standard band for each substrate polymer. The standard bands used were the CH bending vibration at 1400 cm for poly (dimethyl siloxane) and the CF2 scissoring deformation at 1450 cm for fluorinated ethylene/propylene copolymer. Because of the amide I band in polyurethanes, a 4X expanded abscissa was used for the other two polymers, the IX scale was sufflcient. 

Recently, a versatile class of poly(ethylene propylene)/poly(ethylene oxide) block copolymer micelles were introduced they were stable due to a combination of high block incompatibility, kinetically frozen core, and high interfacial tension between core and solvent [53, 58]. Moreover, by using a co-solvent of varying composition, the aggregation number was controlled and soft spheres from star-like to micelle-like could be obtained. Another way is core stabilization via chemical crosslinking, say by UV radiation [59-64]. 

Nonionic Alkyl poly (ethylene oxide), copolymers of poly (ethylene oxide) and poly(propylene oxide), alkyl polyglucosides, and so on. 

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