Ethylene-propylene-ethylidene EPDM

Fig. 7 IR spectra of ethylene-propylene-ethylidene norbornene copolymer (EPDM) (A) before and (B) after photocrossunking.

Keitan 4906. See Ethylene-propylene-ethylidene norbornene Keitan 5300A. See EPDM rubber Keitan 5508. See Ethylene-propylene-ethylidene norbornene Keitan 5531D, Keitan 5636A. See EPDM rubber... 

Keitan 7506. See Ethylene-propylene-ethylidene norbornene Keitan E801. See EPDM rubber KELTONE HV, KELTONE H /CR, KELTON LVCR, KELTONE LVNR, KELTONE . See Algin... 

Trilene 65. See EPDM rubber Trilene 66. See Ethylene-propylene-ethylidene norbornene... 

An EPDM (ethylene-propylene-ethylidene norbornene terpolymer) rubber was dissolved in o-dichlorobenzene with 1 phr of carbon-60. When cast onto a glass slide and dried, an insoluble film exhibiting reversible elasticity forms. 8 refs. 

Commercial grades of ethylene-propylene copolymers (EPR) contain 60-75 mol% of ethylene to minimize crystallization. The addition of a third monomer, such as 1,4-hexadiene, dicyclopentadiene, or 5-ethylidene-2-norbornene, produces generally amorphous faster-curing elastomers. A large number of such terpolymers, referred to as EPDM, is available commercially. Their properties, performance, and response to radiation vary considerably depending on macrostructure, ethylene/propylene ratio, as well as on the type, amount, and distribution of the third monomer. 

As was mentioned, cycloaddition of unactivated hydrocarbons, namely, that of cyclopentadiene, has practical significance. 5-Vinyl-2-norbomene is produced by the cycloaddition of cyclopentadiene and 1,3-butadiene546,547 [Eq. (6.96)] under conditions where side reactions (polymerization, formation of tetrahydroindene) are minimal. The product is then isomerized to 5-ethylidene-2-norbomene, which is a widely used comonomer in the manufacture of an EPDM (ethylene-propylene-diene monomer) copolymer (see Section 13.2.6). The reaction of cyclopentadiene (or dicyclopentadiene, its precursor) with ethylene leads to norbomene548,549 [Eq. (6.97)] 550... 

With larger amount of propylene a random copolymer known as ethylene-propylene-monomer (EPM) copolymer is formed, which is a useful elastomer with easy processability and improved optical properties.208,449 Copolymerization of ethylene and propylene with a nonconjugated diene [EPDM or ethylene-propylene-diene-monomer copolymer] introduces unsaturation into the polymer structure, allowing the further improvement of physical properties by crosslinking (sulfur vulcanization) 443,450 Only three dienes are employed commercially in EPDM manufacture dicyclopentadiene, 1,4-hexadiene, and the most extensively used 5-ethylidene-2-norbomene. 

On-line SEC-NMR has successfully applied to the determination of chemical composition distribution in ethylene-propylene-diene terpolymers (EPDM) by the use of H-NMR at 750 MHz [24], EPDM containing 2-ethylidene-5-norbornene (ENB), as a diene... 

AES (acrylonitrile-EPDM-styrene) is a blend of SAN and EPDM. SAN is a statistic copolymer of styrene and acrylonitrile. EPDM is an elastomeric terpo-lymer of ethylene, propylene and a nonconjugated diene. The diene studied here was 5-ethylidene-2-norbomene. The total content of EPDM was 34mole% [6]. The diene represented 8 mole% of the EPDM and the SAN phase was composed of 80 mole% of styrene and 20 mol% of acrylonitrile. The AES films were irradiated at / > 300 nm at 60 °C in the presence of oxygen. The photoproducts resulting from the photooxidation of each components of AES were identified by FTIR spectroscopy coupled with the same chemical and physical treatments as mentioned above for the previous studies. As pointed out in the literature [17], the EPDM component is more reactive than the copolymer SAN towards photooxidation. 

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... 

Improved ABS-similar resins can be obtained by grafting SAN onto ethylene-propylene-diene terpolymers (EPDMs) which contain, usually, a much lower degree of unsaturation than polybutadiene, thus achieving hi er thermal-oxidative resis-tance However, only EPDMs containing a sufficient amount (7—10 double bonds per 1,000 C atons) of reactive unsaturations, e.g. ethylidene or isopropylidene groups, display a grafting efficiency sufiident to bring about compatibility of the ssy i se with the rubbery one and hence satisfactory final properties. 

Ethylene/propylene co-polymers (usually called EPRs for ethylene-propylene rubbers, or EPMs for ethylene-propylene monomers) are amorphous polyolefins when the propylene content is in the range 30-70%. Despite the typical unreactivity of saturated polyolefins, ethylene-rich EP co-polymers can be made highly elastic by radical cross-linking, but in order to make the rubber vulcanizable , a diene (5-ethylidene-2-norbornene, 1,4-hexadiene, or dicyclopentadiene) is added, which leaves one unreacted double bond available for subsequent cross-linking. These latter materials are called EPDMs (for ethylene-propylene-diene monomers). 

The addition copolymerization of norbornene-type monomers with a-olefins [21] forms the basis of EPDM (ethylene propylene diene monomer) technology. Incorporation of smaU amounts of DCPD or ethylidene norbornene (ENB) in olefinic vinyl addition polymers provides latent crosslink sites in EPDM elastomers. It is weU known in the hterature that incorporation of higher amounts of rigid, bulky multicychc olefins results in materials with higher TgS [22]. In fact, more recent work has concentrated on increasing the Tg of norbornene-type monomer/a-olefin copolymers [23]. The use of late transition metal catalysts to prepare such copolymers is reviewed in Section 4.3. 

Ethylene-propylene copolymers, EPR, and ter-polymers containing diene monomers, EPDM, crosslink on irradiation [Bradley, 1984 Aoshima et al, 1992]. The crosslinking can be enhanced by the use of crosslinking agents for example, EPDM containing 5-ethylidene-2-norborene, ENB, may be efficiently radiation crosslinked. Analogues of reaction (R-30) contribute to such crosslinking. 

In 1975, Du Pont presented an ultra impact strength PA alloy, Zytel-ST, produced by reactive processing of PA66 with maleinated EPDM (copolymer of ethylene, propylene, and 2-ethylidene-5-norbomene) (2). Then followed investigations of... 

The photoinitiated crosslinking of three ethylene-propylene-diene copolymers (EPDM elastomers) has been investigated in a series of studies > > >9. Commercial EPDM samples were used containing the following dienes ethylidene-norbomene (ENB), dicydopentadiene (DCPB) and hexadiene (HD). The main photoinitiators used were benzoyl-1-cyclohexanol (PI) from Ciba-Geigy and 2,4,6-trimethyl-benzoyl diphenylphosphineoxide (APO) from BASF, which both are photofragmenting (formulas 3 and 4) ... 

Copolymerization of ethylene with propylene results in a random, noncrystalline copolymer that is a chemically inert and rubbery material. EPM is a saturated copolymer that can be cross-linked through the combination of the free radicals generated by peroxides or radiation. To incorporate sites for vulcanization, an unsaturated terpolymer can be prepared from ethylene, propylene, and a small amount (3 to 9%) of a nonconjugated diene (EPDM). The diene is either dicyclopentadiene, ethylidene nor-bomene, or 1,4-hexadiene. The resulting unsaturated terpolymer can be vulcanized by traditional techniques. Each of the termonomers confers different characteristics on the final elastomer. 

Elastomeric ionomers have also been developed from ethylene-propylene-diene ternary copolymers known as EPDM rubbers. The diene is commonly ethylidene norbomene. Du Pont made carboxylated ionomers by free-radical grafting of maleic anhydride (0.5—5%) onto the diene moiety of the polymer and neutralized the product with rosin salt. The ethylidene norbomene can also be sulfonated, thus ... 

Copolymerization of ethylene and propylene produces an elastomeric polymer that is virtually inert because of the absence of carbon-carbon double bonds (EPM). Such polymers thus tend to be crossUnked with peroxides or by radiation. To improve the reactivity of ethylene-propylene copolymers, 1-10% of a third monomer can be added to give a terpolymer or ethylene-propylene-diene monomer (EPDM). The primary diene monomers used in EPDM are 1,4-hexadiene, dicyclopentadiene, and ethyUdene norbomene. Introduction of an unsaturated monomer such as ethylidene norbomene will enable use of sulfur-based crosslinking systems. 

When a butyl rubber, an ethylidene norbornene (ENB)-type ethylene propylene diene monomer (EPDM), or a mixture of desired proportions of a butyl rubber and an ENB-type EPDM is thermally crosslinked using an... 

Ethylene propylene diene terpolymers (EPDM) can be used to improve the ozone resistance of bromobutyl/natural rubber binary polymer blends, eliminating the need for chemical antiozonants. Addition of 10 phr of EPDM (with a high ethylidene norbornene, ENB, content of9%) to a 50/50 bromobutyl rubber/natural rubber blend results in a compound vdth good static and dynamic ozone resistance. EPDM with a 5.7% ENB level is another suggested grade of polymer. 

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