摘要 |
Chlorosulfonated polyethylene materials having (a) weight average molecular weight of from about 40,000 to about 300,000, (b) a chemically combined chlorine content of from about 20 to about 50 percent by weight of polymer, (c) a chemically combined sulfur content of from about 0.8 to about 2.5 percent by weight of polymer and (d) a 100 percent modulus of from about 0.6 to about 4.8 megapascals are prepared in an anhydrous process wherein an amorphous chlorinated polyethylene starting material is first fluidized and then exposed to a gaseous mixture of sulfur dioxide and chlorine having a ratio of sulfur dioxide to chlorine of from about 1:1 to about 16:1 in the presence of a chlorine free radical generator such as ultraviolet light, at a temperature of from about 25 DEG to about 100 DEG Centigrade, for a period of two hours or less.
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