合成橡胶工业 |
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m-DVB和p-DVB原子转移自由基聚合动力学 张士福 曾光新 应圣康 摘要:以氯端基聚苯乙烯为大分子引发剂,氯化亚铜/2,2′-联二吡啶为催化剂,邻二甲苯为溶剂,用气相色谱分别研究了对二乙烯基苯(p-DVB)和间二乙烯基苯(m-DVB)在100~130℃的原子转移自由基聚合动力学。结果表明,聚合符合表观一级反应动力学。p-DVB在100,110,120,130℃的聚合速率常数分别为0.072,0.128,0.379,0.546h-1,m-DVB在上述不同温度的聚合速率常数分别为0.043,0.087,0.199,0.310h-1,p-DVB的聚合速率大于m-DVB的。m-DVB和p-DVB聚合的表观活化能分别为84.1kJ/mol和89.2kJ/mol,两数值接近,表明温度对p-DVB和m-DVB原子转移自由基聚合速率的影响程度相当。 Kinetic study on atom transfer radical polymerization of m- DVB and p- DVB Zhang Shifu, Zeng Guangxin and Ying Shengkang Abstract:The kinetics of atom transfer
radical polymerization of p- DVB and m- DVB were investigated by using PSt- Cl as the macroinitiator and CuCl/bpy as the catalyst in o-
xylene at 100~ 130 ℃
. Gas chromatography was used to trace the concentration of
DVB in the polymerization.The results showed that the polymerizations follow the first
order kinetics and p- DVB polymerized faster than m-
DVB. The apparent polymerization rate constants were kp-
DVB,130 ℃ =0.546 h-1, kp- DVB,120
℃ = 0.379 h-1, kp- DVB,110
℃ = 0.128 h-1, kp- DVB,100
℃ =0.072 h-1 for p- DVB and km-
DVB,130 ℃ =0.310 h-1,km- DVB,120
℃ = 0.199 h-1,km- DVB,110
℃ =0.087 h-1, km- DVB,100
℃ =0.043 h-1 for m- DVB. The
apparent polymerization activation energies of m- DVB
and p- DVB which were 84.1 kJ/mol for m- DVB and 89.2 kJ/mol for p- DVB
were close to each other, and this suggested that polymerization temperature exert effect
on the polymerization rate of both p- DVB and m-
DVB to the similar extent. 基金项目:国家自然科学基金资助项目(29634010-2)。 参 考 文 献 1,Wang Jinshan, Matyjaszewski K. Controlled / living radical
polymerization.Atom transfer radical polymerization in the presence of transition metal
complexes[J]. J Am Chem Soc, 1995, 117:5 614 收稿日期:1999-05-31;修订日期:1999-11-22。 |