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Updated: Oct 9, 2025
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Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
Published on: November 27, 2015
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Pressure-Induced Polymerization: Addition and Condensation Reactions
Fang Li1, Jingqin Xu1, Yajie Wang1
1Center for High Pressure Science and Technology Advanced Research, Beijing 100094, China.
Molecules (Basel, Switzerland)
|December 24, 2021
Summary
High pressure induces polymerization in unsaturated organic molecules, forming extended carbon structures. This review details topochemical polymerization and condensation reactions, including small molecule elimination.
Area of Science:
- Materials Science
- Organic Chemistry
- Crystallography
Background:
- Unsaturated organic molecules undergo polymerization under high pressure (1-100 GPa).
- These reactions often result in polymeric materials with extended carbon skeletons.
- Crystalline environments facilitate topochemical polymerization processes.
Purpose of the Study:
- To review topochemical polymerization of alkynes, aromatics, and alkynylphenyl compounds.
- To analyze critical crystal structures, bonding, and product structures.
- To summarize condensation reactions and small molecule elimination during polymerization.
Main Methods:
- Crystallographic analysis of precursor structures.
- Investigation of bonding mechanisms under high pressure.
- Characterization of polymeric products.
Main Results:
- Demonstrated negative enthalpy change driving polymerization.
- Identified specific crystal structures enabling topochemical reactions.
- Observed formation of extended carbon skeletons in products.
- Documented condensation reactions with elimination of molecules like ammonia.
Conclusions:
- Topochemical polymerization under high pressure is an effective route to novel carbon-rich polymers.
- Understanding crystal structures is crucial for controlling polymerization outcomes.
- Condensation reactions play a significant role in the final polymer structure.
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