来自金属催化剂的聚烯的结构性质相关性:立体缺陷,区域常规的异性聚烯
Claudio De Rosa1, Finizia Auriemma, Annunziata Di Capua
1Dipartimento di Chimica, Università di Napoli Federico II, Complesso Monte S. Angelo, Via Cintia, 80126 Naples, Italy.
Journal of the American Chemical Society
|December 23, 2004
概括
新的金属催化剂可以制造出具有可调节性质的定制聚烯. 控制等离子聚烯的区域错误 (rr缺陷) 允许精确调整机械行为,从刚性塑料到柔性热塑料和强弹性体.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
背景情况:
- 金属催化剂可以精确控制聚合物微观结构.
- 隔离性聚烯的性能受到立体规律性和缺陷的影响.
- 区域错误 (rr缺陷) 影响聚烯的多态行为和机械特性.
研究的目的:
- 通过使用新型C(1) - 对称的印第尼尔-安萨-狄诺cyclopentadienyl基conocenes,合成具有不同程度的立体规律性的异构性聚烯.
- 研究区域错误 (rr缺陷) 对聚烯多态行为和机械性能的影响.
- 建立缺陷度,多态形状和材料特性之间的关系.
主要方法:
- 合成MAO激活的C(1) -对称的印尼尔-安萨-狄诺cyclopentadienyl基锡尔科诺.
- 烯的聚合制造以产生具有受控分子量和立体规律性的异性聚烯.
- 分析多态行为 (玛和无序形式的结晶) 和机械性能作为 rr 缺陷度的函数.
主要成果:
- 在rr缺陷的存在诱导了玛形式的结晶和中间无序的修饰.
- 发现了玛形式的数量与异态序列的平均长度之间的线性关系.
- 具有3-4% rr缺陷的聚烯样品具有高点 (130-160°C),并充当硬塑料材料.
- 具有4-6% rr缺陷的样品具有较低的点 (115-120°C) 并表现为柔性热塑性材料.
- 具有7-11% rr缺陷的样品具有80-110°C的点,并作为高强度热塑性弹性体起作用.
结论:
- 金属催化剂的定制设计允许微调聚烯链微观结构.
- 对rr缺陷的控制使得具有各种属性的聚烯的生产成为可能,桥梁刚性塑料和弹性体.
- 这种方法促进了针对特定应用的新型聚烯材料的开发,这些材料具有理想的中间特性.
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