Polyethylene rubber

There have been some attempts to develop chlorinated polyethylene elastomers. The rubbers possess such attractive properties as very good oil, heat, flame, ozone, and weathering resistance and are also available in a convenient powder form. In spite of being marketed at competitive prices, the chlorinated polyethylene rubbers (designated as CM rubbers by ASTM) took... 

Chlorosulphonated polyethylene rubber (Hypalon) has excellent chemical resistance even to oxidative acids at elevated temperatures. When specially compounded it can have excellent abrasion resistance in some operating conditions. 

Akhtar, S. Morphology and Physical Properties of Thin Films of Thermoplastic Elastomers from Blends of Natural Ruhher and Polyethylene, Rubber Chem. Technol. 61, 599-583, 1988. 

As with chlorinated polyethylene rubber, chlorosulphonated polyethylene exhibits good resistance to oxygen, ozone and light. The polar nature of the polymer chain also confers oil resistance. 

Several graft copolymerizations were described by Ballantine (17, 64), Henglein (104, 105) and coworkers. Different monomer-polymer systems were examined styrene on polymethyl methacrylate, poly-2, 5-dichlorostyrene, polytetrafluoroethylene, polyethylene, polypropylene and polyisobutylene, acrylonitrile on polyethylene, rubber, polymethyl methacrylate and dimethyl polysiloxane, vinylpyrrolidone and acroleine on polymethyl methacrylate. The results agree with the preceding ones moreover they show the influence of the swelling and diffusion of the monomer into the polymer. 

Polymer A high-molecular-weight organic compound, natural or synthetic, whose structure can be represented by a repeated small unit, the mer e.g., polyethylene, rubber, cellulose. Synthetic polymers are formed by addition or condensation polymerisation of monomers. If two or more monomers are involved, a copolymer is obtained. Some polymers are elastomers, some plastics. 

ETU is used as an accelerator in the vulcanization of polychloroprene (Neoprene) and other elastomers for coated fabrics, for epichlorohydrin and for chlorosulfonated polyethylene rubbers. It is also an intermediate for antioxidants, insecticides, fungicides, dyes, pharmaceuticals, and synthetic resins. 

Used as a secondary accelerator with antioxidant, antiozonant, and stabilizing function in synthetic rubber and high polymer materials in the plastics and rubber industries. Mainly used in styrene-butadiene rubber (SBR), chloroprene rubber (CR), epichlorohydrin, and chlorosulfonated polyethylene rubber. Promotes heat-resistance of chlorosulfonated polyethylene rubber, EPDM and CSM and sunshine resistance of CR. 

Elastomers include natural rubber (polyisoprene), synthetic polyisoprene, styrene-butadiene rubbers, butyl rubber (isobutylene-isoprene), polybutadiene, ethylene-propylene-diene (EPDM), neoprene (polychloroprene), acrylonitrile-butadiene rubbers, polysulfide rubbers, polyurethane rubbers, crosslinked polyethylene rubber and polynorbomene rubbers. Typically in elastomer mixing the elastomer is mixed with other additives such as carbon black, fillers, oils/plasticizers and accelerators/antioxidants. 

Tensile strengths of chlorosulfonated polyethylene rubber (CSM) vulcanisates are around 3.5 MPa, depending upon formulation. In resilience, the elastomer compares favourably with other synthetic elastomers, though generally its resilience is lower than NR vulcanisates. Flex and abrasion resistance are very good and CSM will not support combustion. 

Property Natural Rubber Butyl Rubber EPDM rubber Chloroprene rubber Nitrile rubber Silicone rubber Chloro sulfon ated polyethylene rubber... 

US Environmental Protection Agency Ethylene-propylene diene terpolymer Expanded polyethylene Rubbers of ethylene-propylene monomer Ethylene-propylene rubber Expanded polystyrene Electrostatic-discharge dissipating... 

Chem. Descrip. Chlorosulfonated polyethylene rubber (89-99%), carbon tetrachloride (< 2%), chloroform (< 0.2%), talc (1%)... 

As a consequence, before 1953, the only possible blends were those of LDPE with other polymers than PO or with elastomers (e.g., chlorosulfonated polyethylene rubber, CSR chlorinated butyl mbber, CBR ethylene/propylene/diene copolymers, EPR, EPDM thermoplastic olefinic elastomer TPE, TPO). However, in addition to the original autoclave polymerization, already in 1938, a tubular reactor was introduced and its product had different properties than that from the autoclave. Also varying the reaction condition affected the degree of short- and long-chain branching in LDPE thus, blending different LDPEs offered a way for optimizing the resin to specific applications. 

---