Homogeneous Models of Ziegler-Natta Catalysts

齐格勒-纳塔催化剂的均相模型

• 批准号: 8917586
• 负责人: Gregory Girolami
• 金额: $ 21.3万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-11-15 至 1993-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8917586&HistoricalAwards=false
• 关键词: Homogeneous; Models; Ziegler; Natta; Catalysts

With support from the Inorganic, Bioinorganic and Organometallic Chemistry Program, Dr. Gregory S. Girolami will synthesize and study soluble models of the heterogeneous catalysts used widely for the industrial synthesis of such polymers as polyethylene, the so-called Ziegler-Natta catalysts. The results of the project are expected to aid in the identification of the species responsible for the catalytic activity and in the formulation of a detailed mechanism for the catalytic process. Homogeneous models of Ziegler-Natta catalysts will be synthesized and studied, with particular emphasis on the preparation and reactivity of electronically unsaturated alkyl derivatives of the early transition elements. Among the effects to be examined are the unexpected spin-state changes which occur as a result of the extremely strong pi-electron donation by the early transition metals, e.g., those of group 4, to ligand acceptor orbitals. Although octahedral geometries are generally assumed for Ziegler-Natta catalysts, d-zero metal alkyls can adopt non-octahedral geometries, and the role of the latter geometries in the catalytic process will be probed. Studies of new chromium-based polymerization systems and mechanistic studies related to the thermolysis of transition metal alkyls will be pursued also.

在无机、生物无机和 有机化学计划，博士格雷戈里S。吉罗拉米将 综合和研究非均质的可解模型 广泛用于工业合成这种化合物的催化剂 聚合物如聚乙烯，即所谓的齐格勒-纳塔 催化剂的该项目的成果预计将有助于 负责催化的物种的鉴定 活动和制定详细的机制， 催化过程 齐格勒-纳塔催化剂的均相模型将 综合和研究，特别强调 电子不饱和烷基的制备和反应性 早期过渡元素的衍生物。在这些影响中， 要检查的是意外的自旋状态变化， 由于极强的π电子捐赠， 早期过渡金属，例如，第4组， 配体受体轨道虽然八面体几何是 通常假定对于齐格勒-纳塔催化剂，d-零金属 烷基可以采用非八面体几何形状， 将探索催化过程中的后一种几何形状。 新型铬系聚合体系的研究 与相变理论有关的机理研究 也可以使用烷基金属。