| 摘要 |
Polymers of at least 75 weight per cent of vinyl chloride are halogenated by reacting a macrogranular vinyl chloride polymer having a specific viscosity of at least 0.4 suspended in an aqueous liquid in the presence of a chlorohydrocarbon swelling agent, illumination and a catalytic amount of a free radical producing agent at a temperature no greater than 65 DEG C. Specified resins are polyvinyl chloride and copolymers of vinyl chloride with vinylide chloride, vinyl acetate, isopropenyl acetate, methyl acrylate, ethyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, acrylonitrile, ethylene, propylene, styrene, a -methyl styrene, and maleic and fumaric esters. The resins are preferably porous with a pore space of 5 to 50% by volume. Specified swelling agents are mono-, di- and trichloro-methane. Many suitable free radical producing agents are specified including metal peroxides and superoxides, inorganic peroxy acids and salts, hydrogen peroxide and peroxyhydrades, organic hydroperoxides and peroxides, peracids and peresters, aldehyde and ketone peroxides, addition compounds of hydrogen peroxide with organic compounds, and aliphatic azo compounds. Examples describe the chlorination of polyvinyl chloride in aqueous suspension in the presence of chloro-form and (1) benzoyl peroxide, (2) potassium persulphate, (3) sodium perborate, (4) hydrogen peroxide, (5) azo bisisobutyronitrile and (6) sodium perborate, potassium persulphate, benzoyl peroxide, hydrogen peroxide and acetyl peroxide.
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