使,

Shogo Amemori1, Kenta Kokado, Kazuki Sada

  • 1Department of Chemical Sciences and Engineering, Graduate School of Chemical Sciences and Engineering, Hokkaido University, Kita-ku, Sapporo, Japan.

概括

研究人员使用小型有机分子设计了热敏聚合物. 这些分子通过键,控制聚合物相变,在较低的临界溶液温度 (LCST) 和较高的临界溶液温度 (UCST) 之间切换行为.

相关概念视频

Polymer Classification: Stereospecificity01:26

Polymer Classification: Stereospecificity

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Polymers02:34

Polymers

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Step-Growth Polymerization: Overview01:03

Step-Growth Polymerization: Overview

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...
Polymer Classification: Crystallinity01:21

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Polymer Classification: Architecture01:14

Polymer Classification: Architecture

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...
Olefin Metathesis Polymerization: Acyclic Diene Metathesis (ADMET)00:53

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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.
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