基托聚乙烯材料来自Pd(II) - 催化共聚合与连续一氧化碳料
Steffen Iberl1, Maria Voccia2, Ida Ritacco2
1Chair of Chemical Materials Science, Department of Chemistry, University of Konstanz, 78464 Konstanz, Germany.
概括
这项研究使用乙烯和一氧化碳共聚合开发了-聚乙烯. 由此产生的材料具有类似高密度聚乙烯的特性,机械性能与HDPE相当.
科学领域:
- 聚合物化学 聚合物化学
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
背景情况:
- 乙烯和一氧化碳的共聚合是功能性多聚烯的关键途径.
- 实现具有理想材料性质的非交替共聚物,需要精确控制单体反应性和催化剂性能.
研究的目的:
- 合成具有类似于高密度聚乙烯 (HDPE) 性能的聚乙烯 (keto-PEs).
- 研究催化剂结构,单体反应性和共聚合物微观结构之间的关系.
- 优化共聚合过程,以生产类似HDPE的材料.
主要方法:
- 选四个Pd(II) 酸硫酸盐催化剂用于乙烯和一氧化碳的共聚合.
- 使用定制的反应堆设置来控制单体料和再压缩.
- 使用密度函数理论 (DFT) 来计算激活自由能量差异.
- 通过拉伸性测试,对基托-PE进行表征,并将其机械性能与HDPE进行比较.
主要成果:
- 具有特定素基因的Pd-2催化剂表现出最高活性,产生分子重量为30-40公斤mol-1.1的共聚物.
- 基托组微观结构与DFT计算的激活自由能量差异有很好的相关性.
- 具有0.5和1.4mol%的基团的化压PEs显示了与HDPE相似的机械性能.
结论:
- 二硫酸催化剂对于非交替的乙烯/CO共聚合是有效的.
- 催化剂设计和反应器工程对于控制共聚合物微观结构和性能至关重要.
- 开发的Keto-PE代表了传统HDPE具有调节性质的有希望的替代品.
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