使用化标签方法对哈夫尼-胺基催化1 octene聚合和链转移的机制研究
Eric S Cueny1, Heather C Johnson1, Bernie J Anding1
1Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States.
Journal of the American Chemical Society
|August 2, 2017
概括
染色体灭标记量化了1 octene聚合中的活性催化剂. 这种方法揭示了聚合物分子重量分布,有助于催化剂优化和机械研究.
科学领域:
- 聚合物化学
- 有机金属化学
背景情况:
- 量化活性催化剂对于理解聚合动力学至关重要.
- 传统的方法与高效,低度的商业催化剂相抗衡.
研究的目的:
- 开发和应用染色体灭标记来量化活性催化剂.
- 使用 hafnium 催化剂研究 1- octene 的聚合机制.
- 将结聚合物与散装聚合物的分子量分布进行比较.
主要方法:
- 结聚合物的染色体火标记.
- 双检测凝透色谱 (GPC) 使用紫外线和折射率 (RI) 检测器.
- 随着时间的推移对单体消耗和活性催化剂度的动态分析.
主要成果:
- 成功量化了活性催化剂度.
- 对Hf结合和散装聚合物观察到不同的分子量分布.
- 确定了预催化剂的最佳激活条件.
- 在聚合物的存在下对结合的聚合物进行选择性标记.
- 证实乙基 (ZnEt2) 不影响Hf的传播速度,但经历了快速,不可逆转的链转移.
结论:
- 染色体灭标记对于研究1 octene聚合中的活性催化剂是有效的.
- 该技术为催化剂行为和链传输过程提供了有价值的机械洞察力.
- 该方法适用于没有专门设备的商业聚合催化剂.
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