以氧桥连双核茂钛配合物（CpTiCl2）2O和甲基铝氧烷（MAO）组成的催化体系实现苯乙烯聚合,详细考察了聚合温度,Al/Ti物质的量比,聚合时间,主催化剂浓度[Ti]等条件对聚合反应的影响。研究发现,升高温度对提高活性有利,但是会导致聚合物等规度降低。聚合产物经差示扫描量热（DSC）,红外光谱（FT-IR）和凝胶渗透色谱（GPC）等手段分析,并经沸丁酮进行抽提分离,证明该催化体系制备的聚苯乙烯链结构主要是全同结构,其等规度可达90%以上,熔点最高可达257.1℃,催化剂活性达3.36×106g PS/（mol.h）。
The mixture of a metallocene（μ-oxo） titanium compound（CpTiCl2）2O with methylaluminoxane（MAO） formed a highly active and isotactic catalyst for the polymerization of styrene with the catalytic activity up to 3.36×106 g PS/（mol·h）.The effect of polymerization temperature,Al/Ti molar ratio,polymerization time,and the main catalyst concentration on the polymerization reaction was investigated in detail.The polymer was characterized by differential scanning calorimetry（DSC）,Fourier transform infrared spectrum（FT-IR） and gel permeation in chromatography（GPC）.The results demonstrate that resulting polymer is predominant isotactic styrene.With the increase of reaction temperature,the catalytic activity increases while the isotacticity of resultant polymer decreases,varying from 85% to 92%.The highest melt point of resultant polystryrene is as high as 257.61 ℃ in this experiment.
参考文献
| [1] | 黄启谷,马力,陈立国,林尚安,付志峰,杨万泰.五甲基环戊二烯三苄氧基钛/甲基铝氧烷/三异丁基铝催化合成的间规聚苯乙烯的结构与性能[J].石油化工,2005(05):470-473. |
| [2] | Xu S;Jia J;Huang J .Synthesis of double silylene-bridged binuclear zirconium complexes and their use as catalysts for olefin polymerization[J].Journal of Polymer Science, Part A. Polymer Chemistry,2007(21):4901-4913. |
| [3] | Luo, S;Shen, B;Li, B;Song, HB;Xu, SS;Wang, BQ .Synthesis, Structures, and Polymerization Catalytic Properties of Doubly Bridged Bis(cyclopentadienyl) Dinuclear (mu-Oxo)titanium Complexes[J].Organometallics,2009(10):3109-3112. |
| [4] | Tomotsu N.;Newman TH.;Malanga MT.;Ishihara N. .Syndiospecific polymerization of styrene[J].Journal of molecular catalysis, A. Chemical,1998(1/3):167-190. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%