摘要
研究了聚偏氟乙烯 (PVDF)自由基引发的氯化反应。考察了各种因素 ,如氯化剂、引发剂的种类及浓度 ,反应介质、反应温度和反应时间的影响 ,确定了合成氯化PVDF的最佳反应条件。采用碱熔法测定氯含量 ,用HNMR进行了结构表征 ,并用溶度参数法、接触角法、DTA TG等方法对PVDF氯化前后的溶解性、附着力、熔点等性能进行了测试。结果表明 ,氯原子成功地引入到了PVDF上 ,当氯含量增加到 8 3 %时 ,氯化PVDF的熔点由 1 63℃降至 1 3 0℃左右 ,附着力也有了明显的改善 ,与水的接触角由 90°降至 5 4°,由不溶于丙酮变为溶于丙酮 ,对甲醇和四氯化碳的溶度参数的变化也说明了氯化PVDF的溶解性能变好 ,由TG曲线可知 ,氯化PVDF的热稳定性比改性前虽有一定的降低 ,但其分解温度仍在 3 0
Poly(vinylidene fluoride)(PVDF) has been modified by free radical chlorination. The effects of reaction conditions on chlorination degree, including chlorine gas flow rate, initiator concentration, dispersing medium, reaction temperature and time were investigated. The chlorinated PVDF was characterized by chemical titration and 1H NMR. Its solubility, adhesivity, softening point, contact angle and thermal property were measured. The results show that the chlorination degree of PVDF could be controlled in the range of 1%～16.3%. With the increase of chlorination degree the melting point of PVDF decreased from 163 ℃ to 130 ℃; the contact angle with H_2O decreased from 90° to 54°. The polymers containing more than 6% chlorine were soluble in acetone. The solubility parameters to methanol and tetrachloro-methane were changed. The chlorinated PVDF appeared to be less stable than PVDF, but its decomposion temperature was yet above 300 ℃.
出处
《应用化学》
CAS
CSCD
北大核心
2003年第1期29-33,共5页
Chinese Journal of Applied Chemistry
基金
教育部高校骨干教师资助计划 (教技司 (2 0 0 ) 65号 )
