丁苯嵌段共聚物的合成  

Synthesis of styrene-butadiene block copolymer

作　　者：杨绮波[1] 钱冬梅 王月霞[1] 尹玲玲[1] 

机构地区：[1]中国石油天然气股份有限公司石油化工研究院,北京100195 [2]兰州石化公司石油化工厂,甘肃兰州730060

出　　处：《弹性体》2012年第2期43-48,共6页China Elastomerics

基　　金：中国石油天然气股份有限公司重点科研项目

摘　　要：以环己烷为溶剂、苯乙烯(St)和丁二烯(Bd)为单体、正丁基锂(n-BuLi)为引发剂、四氢呋喃(THF)为结构调节剂,γ-(2,3-环氧丙氧)丙基三甲氧基硅烷为偶合剂,通过活性负离子溶液聚合得到了丁苯嵌段共聚物。研究了杂质对阴离子聚合的影响,苯乙烯转化率、温度与聚合时间的关系,丁二烯转化率与聚合时间的关系,丁二烯、苯乙烯共聚时转化率与聚合时间的关系,单体比及偶合工艺条件的确定,"游离"聚苯乙烯(PS)、"游离"丁苯共聚物对冲击强度的影响。结果表明,总单体比(St/Bd)为72/28～76/24(质量比)、无规段单体比(St/Bd*)为55/45～62/38(质量比)、THF为单体总质量的0.6%～1.0%时,在(75±5)℃下聚合,(85±5)℃下偶合可得到力学性能较好的丁苯嵌段共聚物,Mw=2.493×105,Mn=8.99×104,相对分子质量分布为2.77。Styrene-butadiene block copolymer was synthesized by living anionic solution polymerization with cyclohexane as solvent,styrene（St）and butadiene（Bd）as monomers,n-BuLi as initiator,tetrahydrofuran as structure regulator,γ-glycidoxy propyl-trimethoxy silane as coupling agent and by one-stage addition of initiator and two-stage addition of monomers and one-arm molecular chain end modified with butadiene,and then by adding coupling agent.The effects of impurities such as water,oxygen,alkyne and alchol on the anionic solution polymerization were discussed.The conditions of the polymerization process were studied,such as relationship between conversions,temperature and polymerization time of styrene homopolymerization,relationship between conversions and polymerization time of butadiene homopolymerization,relationship between conversions and polymerization time of styrene-butadiene copolymerization,mass ratio of styrene/butadiene.The effects of free PS/SB on impact strength were discussed.The results showed that the styrene-butadiene block copolymer with number-average molecular mass of 8.99×104,weight-average molecular mass of 2.493×105,its distribution of 2.77 could be obtained at polymerization temperature（75±5）℃,St/Bd（total mass ratio）was 72/28~76/24,St/Bd＊（radom mass ratio）was 55/45~62/38,THF was 0.6%~1.0%（total monomers mass）,coupling reaction temperature（85±5）℃,and under this conditions the styrene-butadiene block copolymer had better mechanical properties.

关 键 词：苯乙烯 丁二烯 正丁基锂 结构调节剂 丁苯嵌段共聚物 负离子溶液聚合 封端 偶联反应 

分 类 号：TQ325.2[化学工程—合成树脂塑料工业]