| 摘要 |
<p>In a process for the chlorination of powdered high pressure polyethylene in the solid state, the chlorination is started at temperatures not exceeding 65 DEG C. and with a chlorine concentration in the feed gas not exceeding 25% by volume, and in the course of chlorination the temperature is raised to a value not exceeding 130 DEG C. and the chlorine concentration in the feed gas to a value in the range 25 to 100%. The process may be effected in a single stage in which temperature and chlorine concentration are progessively increased, or in two stages in the first of which the temperature does not exceed 65 DEG C. and the chlorine concentration does not exceed 25% until a product having a chlorine content of 3 to 15 weight per cent is obtained, whereafter the temperature and chlorine concentration are increased. The chlorination may be effected in the presence of ultra-violet light.</p> |
