Ethylene/propylene/non-conjugated diene

The only important industrial applications of such soluble catalysts are of those prepared from VC14, VOCl3, V(Acac)3, VO(OEt)Cl2, VO(OEt)2Cl, VO(OEt)3 or VO(OBu)3 as precursors and AlEt3, AlEt2Cl or AI(/-Buj2CI as activators, in heptane solution, by which ethylene/propylene copolymers and ethylene/propylene/non-conjugated diene terpolymers are produced [72]. The AW molar ratio in these catalysts does not usually exceed a value of 3 1. 

Explain why 1,4-hexadiene, but not 1,5-hexadiene, is used for obtaining ethylene/ propylene/non-conjugated diene vulcanisable terpolymers. 

A modified ethylene/propylene/non-conjugated diene (EPDM) elastomer, Royaltuf X330 (Uniroyal Chemical), is offered as a toughness improver for PBT and produced as a finely dispersed phase, for easy processing. 

Composition Maleic anhydride modified ethylene/propylene/ non-conjugated diene elastomer Physical Form Rubber Pellets Specific Gravity 0.85 Total Maleic Anhydride/Acid 0.5%... 

Composition Styrene/acrylonitrile (SAN) modified ethylene/ propylene/non-conjugated diene elastomer Physical Form Plastic Pellets Specific Gravity 0.98 Melt Flow Rate (265/21.6) 20g/10 min. 

EPDM terpolymers of ethylene, propylene, and a small percentage of a non-conjugated diene, which makes the side chains unsaturated. 

Random ethylene/propylene copolymers are amorphous and represent an interesting class of synthetic elastomers. The introduction of double bonds, useful for sulphur vulcanisation in the copolymer, can be achieved by copolymerisation of ethylene and propylene with non-conjugated dienes containing only one double bond capable of insertion for instance, 1,4-hexadiene, dicy-clopentadiene and 5-ethylidene-2-norbornene (endocyclic double bond)... 

Important copolymerizations with Ziegler-Natta catalysts are between hydrocarbon monomers. An example is the reaction of ethylene, propylene, and a non-conjugated diene, such as 5-ethylidene-2-norbornene, to produce the so-called EPDM (ethylene-propylene-diene monomer) elastomers. These products have... 

Atactic poly(methyl methacrylate) Atactic polystyrene Butyl-rubber Chlorinated polyethylene Deuterated high density polyethylene Ethylene butylacrylate Elastomeric copolymer from ethylene and ethyl acrylate Elastomeric terpolymer from ethylene, propylene and a non-conjugated diene Elastomeric ethylene-propylene... 

Triple ethylene-propylene rubbers of SKEP(T) brands contain up to several percents of non-conjugated dienes predominantly dicyclopentadiene (DCPD) and ethylidennorbomene (ENB) as third comonomers [177]. 

The major commercial use of propylene oxide is as a comonomer for copolymerization. The block copolymerization with ethylene oxide produces water-soluble detergents. The copolymerization of propylene oxide with non-conjugated dienes produces sulfur-vulcanizable, oil-resistant elastomers that remain rubber-like at low temperatures. The elastomers obtained by the copolymerization of propylene oxide with allyl glycidyl ether have only poor oil resistance, but have good ozone resistance and remain rubberlike at low temperatures. 

Orientations in elongated mbbers are sometimes regular to the extent that there is local crystallization of individual chain segments (e.g., in natural rubber). X-ray diffraction patterns of such samples are very similar to those obtained from stretched fibers. The following synthetic polymers are of technical relevance as mbbers poly(acrylic ester)s, polybutadienes, polyisoprenes, polychloroprenes, butadiene/styrene copolymers, styrene/butadiene/styrene tri-block-copolymers (also hydrogenated), butadiene/acrylonitrile copolymers (also hydrogenated), ethylene/propylene co- and terpolymers (with non-conjugated dienes (e.g., ethylidene norbomene)), ethylene/vinyl acetate copolymers, ethyl-ene/methacrylic acid copolymers (ionomers), polyisobutylene (and copolymers with isoprene), chlorinated polyethylenes, chlorosulfonated polyethylenes, polyurethanes, silicones, poly(fluoro alkylene)s, poly(alkylene sulfide)s. 

EPT, EPTR Ethylene, propylene, and a non-conjugated diene terpolymer, also EPDM... 

Polymerisation of ethylene and propylene results in a saturated copolymer. To vulcanise this rubber, some unsaturation must be introduced. This is commonly done by adding a few percent of non-conjugated diene (termonomer) such as dicyclopentadiene, 1,4-hexadiene, or ethylidene norbornene, during polymerisation. Because only one of the double bonds of the diene reacts during polymerisation, the other is free for... 

For many years Ziegler-Natta coordination copolymerization of ethylene with propylene and non-conjugated dienes (such as hexa-1,4-diene and 5-ethylidene-2-norbornene) has been used to prepare an important class of rubbers known collectively as EPDM rubbers. More recently, copolymerization of ethylene with small proportions of higher a-olefins (such as but-l-ene, hex-l-ene and oct-l-ene) has become important and is used to prepare a range of copolymers known as linear low-density polyethylenes (LLDPE). 

In the ethylene-propylene copolymers described above there are virtually no double bonds consequently vulcanization by conventional techniques using sulphur is not possible and peroxides have to be used. This limitation may be overcome by introducing unsaturation into the polymer by use of a third monomer in the copolymerization process. The third monomer is a non-conjugated diene one of its double bonds enters into the polymerization... 

Ethylene propylene copolymers (EPM) are made by Ziegler-Natta and metallocene polymerization and are the commercial mbbers with the lowest density. EPM cannot be vulcanized and thus is not reactive to peroxide curing. To introduce an unsaturated site suitable for crosslinking, a non-conjugated diene termonomer such as ethylidene norbomene, 1,4 hexaadiene or dicyclo-pentadiene, is employed to produce the mbber known as EPDM. Ethylene propylene diene mbber has small number of double bonds, external to the backbone, introduced in this way. In EPDM, the E stands for ethylene, the P for propylene, the D for diene and the M indicates that the mbber has saturated chain of the polymethylene type, properties of EPM and EPDM are ... 

Coordination polymerisation via re complexes comprises polymerisation and copolymerisation processes with transition metal-based catalysts of unsaturated hydrocarbon monomers such as olefins [11-19], vinylaromatic monomers such as styrene [13, 20, 21], conjugated dienes [22-29], cycloolefins [30-39] and alkynes [39-45]. The coordination polymerisation of olefins concerns mostly ethylene, propylene and higher a-olefins [46], although polymerisation of cumulated diolefins (allenes) [47, 48], isomerisation 2, co-polymerisation of a-olefins [49], isomerisation 1,2-polymerisation of /i-olcfins [50, 51] and cyclopolymerisation of non-conjugated a, eo-diolefins [52, 53] are also included among coordination polymerisations involving re complex formation. 

Pinenes have also been used as feedstock to prepare several linear non-conjugated non-terpenic dienes (e.g. 3,7-dimethyl-l,6-octa-l,6-diene and 5,7-dimethylocta-l,6-diene) used in the synthesis of elastomeric ethylene-propylene-diene terpolymers [14]. 

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