四氢呋喃对反应挤出苯乙烯/异戊二烯共聚物微观结构的影响

Effects of Tetrahydrofuran on the Structure of Styrene/Isoprene Copolymers Polymerized by Reactive Extrusion

为研究极性调节剂对反应挤出苯乙烯类共聚物微观结构的影响,以双螺杆挤出机为反应器,有机锂为引发剂,四氢呋喃(THF)为极性调节剂,采用苯乙烯/异戊二烯(S/I)混合单体一次加料反应挤出技术合成了S/I共聚物,1H-NMR、GPC、DMA和TEM的分析结果表明:THF提高了共聚物的3,4-结构异戊二烯含量,使分散相尺寸变得细小且均匀,两相相容性提高;共聚物链段中长嵌段聚苯乙烯含量较少,并与大量分布较均匀的聚苯乙烯短嵌段、聚异戊二烯短嵌段以及无规共聚的苯乙烯单元共同组成完整的分子链。

By means of the closely intermeshing twin-screw extruder as the reactor, tetrahydrofuran （THF） as the polar additive, mixed styrene （S） and isoprene （I） as the monomer, a S/I eopolymer was synthesized by reactive extrusion in order to study the microstructure. The effects of THF on the structure of the S/I copolymers were studied. It was proved by results of ^1H-NMR,GPC,DMA and TEM, that the content of 3,4-PI was increased with the fedding of THF, the domain of the disperse phase became smaller with homegenous distribution, the compatibility of different phases was improved. In the chain of the prepared copolymen there was few long PS blocks, the copolymer chain was made up of many evenly dispersed short PS blocks, shorter PI blocks, and random styrene to form the whole molecular chain.