催化乙烯/1-基共聚合物到线性低密度聚乙烯的共纳体活性趋势
Gianluigi Galasso1, Roberta Cipullo1, Vincenzo Busico1
1Department of Chemical Sciences, Federico II University of Naples, via Cinthia, 80126 Napoli, Italy.
Polymers
|September 13, 2025
概括
更高的1-基,如1-基和1-基,与聚乙烯生产中的分子催化剂具有相似的反应性. 然而,随着齐格勒-纳塔催化剂的使用,1-十烯反应性显著下降,这表明表面效应占主导地位.
科学领域:
- 聚合物化学 聚合物化学
- 催化科学 催化科学
背景情况:
- 线性低密度聚乙烯 (LLDPE) 的性能通过与1-基因共聚乙烯来调整.
- 较高的1-改进了LLDPE的特性,但与传统的齐格勒-纳塔 (ZN) 催化剂反应性较差.
- 了解comonomer反应的分子动力学因素对于催化剂的开发至关重要.
研究的目的:
- 使用各种分子和ZN催化剂,研究1-hexene和1-decene与乙烯的反应率.
- 为了阐明LLDPE合成中较高的1-基的动态行为.
- 为了比较不同催化剂系统的共同分子反应性.
主要方法:
- 使用高通量实验 (HTE) 工作流来进行反应性测量.
- 采用了明确的金属和后金属分子催化剂.
- 与标准的MgCl2/TiCl4齐格勒-纳塔催化剂的反应性进行比较.
主要成果:
- 1-hexene和1-decene与分子催化剂具有几乎相同的反应性.
- 与1-hexene相比,仅使用ZN催化剂观察到1-decene反应性的显著降低.
- 这表明表面效应在更高的1-基因的ZN催化中起着主导作用.
结论:
- 分子催化剂在LLDPE生产中为更高的1-烯提供一致的反应性.
- 使用更高的1-基因的齐格勒-纳塔催化剂性能对表面相互作用敏感,而不仅仅是金属协调.
- 结果为有效的LLDPE合成提供了对催化剂设计的见解.
相关概念视频
Free-Radical Chain Reaction and Polymerization of Alkenes
9.4K
The conversion of alkenes to macromolecules called polymers is a reaction of high commercial importance. The structure of the polymer is defined by a repeating unit, while the terminal groups are considered insignificant. The average degree of polymerization represents the number of repeating units in the polymer molecule and is denoted by the subscript n.
9.4K
Olefin Metathesis Polymerization: Acyclic Diene Metathesis (ADMET)
2.2K
Acyclic diene metathesis polymerization or ADMET polymerization involves cross-metathesis of terminal dienes, such as 1,8-nonadiene, to give linear unsaturated polymer and ethylene. As ADMET is a reversible process, the formed ethylene gas must be removed from the reaction mixture to complete the polymerization process.
Similar to cross-metathesis, ADMET also involves the formation of metallacyclobutane intermediate by [2+2] cycloaddition of one of the double bonds of a terminal diene with...
Similar to cross-metathesis, ADMET also involves the formation of metallacyclobutane intermediate by [2+2] cycloaddition of one of the double bonds of a terminal diene with...
2.2K
Olefin Metathesis Polymerization: Overview
2.5K
Recently, the development of olefin metathesis polymerization advanced the field of polymer synthesis. Simply put, the reorganization of substituents on their double bonds between two olefins in the presence of a catalyst is known as the olefin metathesis reaction. The use of metathesis reaction for polymer synthesis is called olefin metathesis polymerization.
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists of a...
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists of a...
2.5K
Step-Growth Polymerization: Overview
4.3K
Step-growth or condensation polymerization is a stepwise reaction of bi or multifunctional monomers to form long-chain polymers. As all the monomers are reactive, most of the monomers are consumed at the early stages of the reaction to form small chains of reactive oligomers, which then combine to form long polymer chains in the late stages. Hence, the reaction has to proceed for a long time to achieve high molecular weight polymers.
Many natural and synthetic polymers are produced by...
Many natural and synthetic polymers are produced by...
4.3K
Characteristics and Nomenclature of Copolymers
3.2K
Copolymers are the products obtained from the polymerization of multiple monomer species. So, in a polymer chain itself, there can be multiple repeating units that come from different monomers. The process of synthesizing a polymer from different monomer species is called copolymerization. When two monomers are involved, the polymer is known as a bipolymer. Polymers with three and four monomers are termed terpolymers and quaterpolymers, respectively. Figure 1 depicts the copolymerization of...
3.2K
Polymer Classification: Architecture
3.7K
Polymers are classified as linear or branched on the basis of their chain architecture. The polymer chains in linear polymers have a long chain-like structure with minimal to no branching at all. Even if a polymer features large substituent groups on the monomer, which appear as branches to the skeleton, it is not considered a branched polymer. A branched polymer contains secondary polymer chains that arise from the main polymer chain. The branching occurs when the polymer growth shifts from...
3.7K


