索式萃取法测定聚丙烯腈原丝的含油率

Soxhlet extraction determination of oil content of polyacrylonitrile precursor

采用索氏萃取法测定聚丙烯腈(PAN)原丝的含油率,分析了萃取剂配比、萃取温度、萃取时间及萃取次数对测试结果的影响,探讨了原丝含油率与灰分含量之间的关系。结果表明:采用索氏萃取法测试PAN原丝含油率的最佳条件为萃取剂甲醇和氯仿体积比为1/1.5～1/2.5,萃取温度为80～85℃,萃取时间为2.5 h,萃取次数为1;此方法的回收率为97.8%～103.1%,相对标准偏差为1.14%,但该法只能测试PAN原丝表面的油剂含量,渗透至原丝内部的油剂难以萃取出来,可通过烧蚀后的灰分含量来反映。

The oil coment of polyacrylonitrile （PAN） precursor was determined by soxhlet extraction method. The effects of ex- tractant proportion and extraction temperature, time and number on the determination results were analyzed. The relationship be- tween oil and ash contents was discussed. The results showed that the Soxhlet extraction determination had the recovery rate of 97.8% - 103.1% and relative standard deviation of 1.14% under the conditions of methanol and chloroform extractants at the volume ratio of 1/1.5 - 1/2.5, extraction temperature 80 - 85℃, extraction time 2.5 h, extraction number 1 ; and this method could be only used to determine the oil content on the surface of PAN precursor as the ashes after high-temperature burning could be a reflection of oil content in fiber interior due to the difficulties in extracting the oil out of the fiber.