Chlorosulfonated polyethylene compounding

The polymer requires compounding with normal fillers to produce useful compounds. Chlorosulfonated polyethylene (CSM) excels in resistance to attack by oxygen, ozone, corrosive chemicals, and oil, and in addition has very good electrical properties. Electrical stability and resistance to corona and arc are good. The physical properties and abrasion resistance are also good. Light-colored goods made from CSM have excellent color-fastness. Due to the presence of chlorine atoms, this elastomer shows excellent flame resistance. 

Power Cables. The materials mosdy used to produce power cables are ethylene copolymers loaded with conductive carbon black for semiconductive shielding layers, polyethylene or ethylene—propylene mbber-based compounds as insulations, and either thermoplastic materials (eg, polyethylene, PVC) or thermosetting (based on chlorinated polyethylene (CPE), chlorosulfonated polyethylene (CSPE), chloroprene, etc) for jackets. 

Pyrolysis products of chlorinated polyethylene contain molecules similar to those found in polyethylene pyrolysates and, in addition, compounds similar to that obtained from vinyl chloride (significant amount of HCI). Chlorosulfonated polyethylene typically contains only about 1.5% sulfur, but sulfur-containing compounds such as SO2 can be detected among its pyrolysis products. The distribution of chlorine atoms in chlorinated polyethylene has been investigated using Py-GC [55, 56]. The polymer was considered equivalent with a terpoiymer poly[ethylene-co-(vinyl chloride)-co-(1,2-dichloroethylene)]. The level of specific degradation products such as aromatic molecules (benzene + toluene + styrene + naphthalene), chlorobenzene, and dichlorobenzenes correlates well with the carbon/chlorine ratio in the polymer. 

The chemical name for Hypalon is chlorosulfonated polyethylene and it has excellent resistance to heat, ozone and oxidising chemicals and has good abrasion resistance. It can be compounded for outstanding resistance to oxidising chemicals, such as sodium hypochlorite solutions in sulfuric acid saturated with chlorine and concentrated phosphoric acid. It is one of the few synthetic rubbers that can be mixed in any colour without loss in mechanical properties. 

In the presence of light, halogens attack both vulcanised and unvulcanised butyl rubber. Whether vulcanised or unvulcanised the effect of the reaction is to produce rapid deterioration in molecular weight. A strip of butyl vulcanisate suspended in bromine gas degrades rapidly. In a few minutes the specimen becomes fluid enough to drip to the bottom of the vessel. Chlorosulfonated polyethylene is resistant to ozone being better than Neoprene and butyl rubber compounds [18]. 

Most compounders use a combination of physical and chemical antiozonants and achieve excellent protection in this way. For more severe ozone-resistance problems, there are, of course, a number of specialty elastomers that are saturated and therefore completely ozone-resistant ethylene/propylene rubber, chlorinated and chlorosulfonated polyethylene, ethylene/vinyl acetate, ethylene/acrylic esters, butyl rubber, SEES, plasticized PVC, butyl acrylate copolymers, polyepichlorohydrin and copolymers, polyetherester block copolymer, polyurethane, and silicone. 

Flexible permanent magnets are used for signs, electric motors, toys, sealing strips, etc. They are fabricated from compounds with up to 90 percent by weight of magnetizable filler. Binders can be chlorinated and chlorosulfonated polyethylene, various vinyl compounds, nitrile rubber, and ethylene/ethyl aaylate copolymers. Magnetization is typically accomplished, via a magnetic field, after extrusion. 

Within solvent release type thermosetting sealants, there are Neoprene, hutadiene-styrene, chlorosulfonated polyethylene, EPDM, and silicones. Solvent release types constitute the largest variety of sealants and are composed of three parts (1) the liquid portion of the compound which is the basic non-volatile polymer/elastomeric vehicle, (2) the pigment component, and a (3) solvent or thinner component used to ease the process and to control the thickness. The sealant is cured and its required viscosity is controlled by the evaporation of solvent. 

EPDM successfully competes with other rubbers (butyl, chloroprene, and chlorosulfonated polyethylene) and other materials (PVC, bitumen compounds, and composites), offering quite satisfactory ageing/weathering characteristics associated with good/excellent mechanical properties at a rather low cost. Table 29 illustrates such an application. 

Common release agents for CSM chlorosulfonated polyethylene are stearic acid, paraffin and microcrystalline waxes, petrolatum, and polyethylene glycol. Zinc stearate should be avoided in compounds designed for heat resistance, because of a potential negative effect on aging [8]. For mineral-reinforced compounds that tend to stick and split on the calender and null roUs, use a combination of 1 % Stmktol WB... 

The Handbook of Specialty Elastomers was conceived as a single reference source for the rubber compounder with some experience in designing parts in the rubber industry. The definition of specialty elastomers referenced in this publication is heat, oil, fuel, and solvent-resistant polymers that include polychloroprene (CR), nitrile rubber (NBR), hydrogenated nitrile rubber (HNBR), fluoroelastomer (FKM), polyacrylate (ACM), ethylene acrylic elastomer (AEM), polyepichlorohydrin (CO, ECO), chlorinated polyethylene (CPE), chlorosulfonated polyethylene (CSM), ethylene vinyl acetate (EAM), and thiokol (T). 

Alkanes can be simultaneously chlorinated and chlorosulfonated. This commercially useful reaction has been appHed to polyethylene (201—203). Aromatics can be chlorinated on the ring, and in the presence of a free-radical initiator alkylaromatic compounds can be chlorinated selectively in the side chain. King chlorination can be selective. A patent shows chlorination of 2,5-di- to 2,4,5-trichlorophenoxyacetic acid free of the toxic... 

Examples are the sulfonating of polyethylene film with chloro-sulfonic acid (60) the sulfonating of sheets of phenolformaldehyde resin (77) the treatment of a film consisting of polystyrene and polyvinylchloride with concentrated sulfuric acid (4) the sulfonating of films consisting of aliphatic vinylpolymers with chlorosulfonic acid (125) the sulfonating of copolymers of a monovinyl- and a polyvinyl compound (30). Also are used copolymers of aromatic monovinyl-compounds and linear aliphatic polyene hydrocarbons (3) copolymers of an unsaturated aromatic compound and an unsaturated aliphatic compound (76), and of reaction products of poly olefines and partially polymerized styrene (173). 

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