活性负离子丁苯共聚的偶联反应

以正丁基锂为引发剂、丁二烯和苯乙烯为单体、自制不对称醚为结构调节剂、二乙烯基苯(DVB)为偶联剂,采用负离子共聚法合成丁苯共聚物,考察了偶联时间和偶联温度对偶联反应的影响,并与常规偶联剂四氯化锡进行了对比。对不同偶联时间下偶联产物的支化结构进行了表征分析。结果表明,随着偶联时间的延长,丁苯共聚物的分子量分布加宽,偶联效率增大,偶联10min时的偶联效率可超过50%,最高达58.2%;偶联产物的重均臂数增大,可达9臂,均优于采用四氯化锡者。当偶联温度为40~70℃时,偶联温度对偶联效率的影响较小。未偶联聚合物溶液的特性黏数与聚合物相对分子质量的关系曲线接近呈线性,符合Mark—Houwink方程...

Full description

Saved in:
Bibliographic Details
Published in合成橡胶工业 Vol. 40; no. 1; pp. 7 - 11
Main Author 邱思宇 滕林 杨晓雪 高嘉兴 张春庆
Format Journal Article
LanguageChinese
Published 大连理工大学高分子材料系辽宁省高分子科学工程重点实验室,辽宁大连,116024 2017
Subjects
Online AccessGet full text

Cover

Loading…
More Information
Summary:以正丁基锂为引发剂、丁二烯和苯乙烯为单体、自制不对称醚为结构调节剂、二乙烯基苯(DVB)为偶联剂,采用负离子共聚法合成丁苯共聚物,考察了偶联时间和偶联温度对偶联反应的影响,并与常规偶联剂四氯化锡进行了对比。对不同偶联时间下偶联产物的支化结构进行了表征分析。结果表明,随着偶联时间的延长,丁苯共聚物的分子量分布加宽,偶联效率增大,偶联10min时的偶联效率可超过50%,最高达58.2%;偶联产物的重均臂数增大,可达9臂,均优于采用四氯化锡者。当偶联温度为40~70℃时,偶联温度对偶联效率的影响较小。未偶联聚合物溶液的特性黏数与聚合物相对分子质量的关系曲线接近呈线性,符合Mark—Houwink方程;随着偶联时间的延长,支化曲线偏离线性,偶联产物的支化程度增强,支化比率逐渐下降。
Bibliography:QIU Si-yu, TENG Lin, YANG Xiao-xue, GAO Jia-xing, ZHANG Chun-qing ( Liaoning Provincial Key Laboratory of Polymer Science and Engineering, Department of Polymer Science and Engineering, Dalian University of Technology, Dalian 116024, China)
62-1036/TQ
poly (butadiene-co-styrene) ; anioniccopolymerization ; divinyl benzene ; asymmetricether ; coupling reaction ; branching ratio
Poly (butadiene-co-styrene) was syn- thesized by anionic copolymerization, using n-BuLi as initiator, butadiene and styrene as monomer, self- made asymmetric ether as modifier, divinyl benzene (DVB) as coupling agent, effects of coupling time and coupling temperature on coupling reaction with DVB were investigated compared with those using with SnCl4 as coupling agent, and the branching structures of coupled polymers at different coupling times were characterized. The results showed that with increasing coupling time, the polydispersity in- dex of the coupled polymers broaden, coupling effi- ciency increased and reached over 50% (maximum 5
ISSN:1000-1255