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Updated: May 30, 2025

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
07:28

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization

Published on: November 27, 2015

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チェーン転送ポリメリゼーションによる円形ポリプロピレン型の材料のためのテレケリック・アイソタクティック・ポリプロピレンの合成

Zonglun Yu1, Xing-Wang Han2, Peizhi Li2

  • 1State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China.

Journal of the American Chemical Society
|January 27, 2025
PubMed
まとめ

研究者は,純粋なテレケリックポリプロピレン (tPP) を作成する新しい方法を開発し,改善された特性と持続可能性を持つ円形ポリプロピレンの合成を可能にしました. 先進的なポリプロピレン材料を 開発する際の限界を克服しました

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Polymer Classification: Stereospecificity

Polymerization generates chiral centers along the entire backbone of a polymer chain. Accordingly, the stereochemistry of the substituent group has a significant effect on polymer properties. Polymers formed from monosubstituted alkene monomers feature chiral carbons at every alternate position in the polymer backbone. Relative to the predominant orientation of substituents at the adjacent chiral carbons, the polymer can exist in three different configurations: isotactic, syndiotactic, and...
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The polymerization process that involves carbanion as an intermediate is called anionic polymerization. It is also a type of addition or chain-growth polymerization. Anionic polymerization gets initiated by a strong nucleophile such as an organolithium or a Grignard reagent. The most commonly used initiator for anionic polymerization is butyl lithium. Monomers involved in anionic polymerization must possess a vinyl group bonded to one or two electron-withdrawing groups. For instance,...
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