Chlorosulphonated Polyethylene CSM

Chlorosulphonated polyethylene was first introduced by DuPont as Hypalon, a trade name in the year 1952. Chlorosulphonated polyethylene compounds have good heat and oxygen and ozone resistance, moderate oil resistance and excellent electrical properties, but their main features for use in the chemical process industries is their resistance to strong oxidizing chemicals. 

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Chlorinated (CM) and chlorosulphonated polyethylenes (CSM and ACSM)— this chapter... 

Chlorosulphonated Polyethylene (CSM, CSPE) Designation in ISO 1629 - CSM Repeat Unit... 

PAS-FTIR spectra have been used to find out the interaction of chlorosulphonated polyethylene (CSM) and carbon black N110 [48]. A number of bands in the 1800 cm1-1680 cm1 region in the spectrum of Nil0 (Figure 2.7) confirm the presence of different carbonyl functionalities, which may include carboxyl group, lactone and quinone. The band at 1651 cm1 is characteristic of aromatic double bonds in the carbon black. The... 

At room temperature, PE is a semi-crystalline plastomer (a plastic which on stretching shows elongation like an elastomer), but on heating crystallites melt and the polymer passes through an elastomeric phase. Similarly, by hindering the crystallisation of PE (that is, by incorporating new chain elements), amorphous curable rubbery materials like ethylene propylene copolymer (EPM), ethylene propylene diene terpolymer (EPDM), ethylene-vinyl acetate copolymer (EVA), chlorinated polyethylene (CM), and chlorosulphonated polyethylene (CSM) can be prepared. 

Lead stabilisers have been used in a variety of PVC as well as other polymers for many years. In some halogenated polymers, such as chlorinated PE (CPE), chlorosulphonated polyethylene (CSM), polychloroprene (CR) and epichlorohydrin (ECO), dibasic lead phthalate and dibasic lead phosphite are used to scavenge HC1 arising from crosslinking as well as from degradation. In some of these cases, the metal may participate in crosslink formation. With lead-based stabilisers, the result is typically a product with greater water and chemical resistance than if a light metal, with more soluble halide salts, were used instead. In other cases, lead stabilisers may be used solely for function in metal oxide... 

Chlorosulphonated polyethylene (CSM). A synthetic rubber produced by reacting polyethylene with chlorine and sulphur dioxide. Its products have good weather resistance even in light colours. Applications technical rubber goods, roofing sheets, fabric coatings, film-forming component in lacquers and paints. Trade name Hy-palon (USA). 

Roychoudhury et al. showed that the double peak of a blend of ENR-50 with chlorosulphonated polyethylene (CSM) at 1 1 weight ratio was changed to a single one (at 2.7 °C) when carboxylated nitrile rubber (XNBR) was added in the stock at 50 wt% (i.e. ENR-50/CSM/XNBR 25/25/50). Additionally, an exothermic peak was detected at 205 °C during a differential thermal analysis of a 33.3/33.3/33.3 mixture of this ternary blend. Taking into consideration that CSM, XNBR and ENR are soluble in chloroform whereas their blend is insoluble, the exothermic peak was attributed to self-crosslinking behaviour of this ternary compound (in the absence of curatives). 

DuPont have produced a modified chlorosulphonated polyethylene based polymer (trade name Acsium). In this modified polymer the chlorine content is reduced, but an additional pendant alkyl group is used to restrict the ability of the polymer to crystallise. The result is a polymer with a lower Tg than the conventional CSM polymer. 

CSM. Symbol for chlorosulphonated polyethylene according to the International Standard ISO R 1629. 

Of much longer commercial standing than the chlorinated polyethylene elastomers are the so-called chlorosulphonated polyethylenes (designated as CSM Rubbers) marketed by Du Pont since 1952 under the trade name Hypalon. These are essentially chlorinated polyethylenes which in addition possess a small amount of —SO2CI side chains to provide a useful cure site. Whilst most rubbers are shrouded in anonymity as far as the general public is concerned these speciality materials have a merited excellent and enviable reputation with outdoor pursuit enthusiasts with uses in such areas as groundsheets and inflatable dinghies. 

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