Influence of (1,3‐phenylene)bis(3‐methyl‐1‐phenyl pentylidene)dilithium initiator concentration on the modality of polybutadiene
作者:Thodoris C. Vasilakopoulos、Nikos Hadjichristidis
DOI:10.1002/pola.26435
日期:2013.2.15
The strong influence of (1,3‐phenylene)bis(3‐methyl‐1‐phenyl pentylidene)dilithium initiator (DLI) concentration on the modality of polybutadiene (PBd) in the presence of lithium s‐butoxide (s‐BuOLi) in benzene, at room temperature, has been studied. The quality of DLI has been evaluated by gas chromatography‐mass spectrometry (GC‐MS) and 1H NMR. Keeping s‐BuOLi/C‐Li ratio (R) close to unity, at relatively
(1,3-亚苯基)的强烈影响双在聚丁二烯上的在存在模态(PBD)(3-甲基-1-苯基戊基)二锂引发剂(DLI)浓度锂小号丁醇(小号-BuOLi)在已经研究了室温下的苯。DLI的质量已通过气相色谱-质谱(GC-MS)和1 H NMR进行了评估。在相对较高的DLI浓度(C > 7×10 -4 M)下,使s -BuOLi / C-Li之比(R)接近于1,获得多分散指数小于1.07的单峰高1,4-PBds,而双峰较低浓度的那些(C <6×10 -4M)。已使用尺寸排阻色谱法对聚合期间和聚合结束时采集的样品评估了C-Li浓度对PBd形态的影响。粘度观察也已被用于进一步支持该结果。尽管使用了高真空技术,但在低引发剂浓度下,由于聚合溶液中不可避免地存在质子杂质,PBd的双峰性归因于部分终止的双官能团物种。此外,1 H NMR证实了s -BuOLi对PBd微观结构的强烈影响。©2012 Wiley Periodicals,Inc