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Updated: Jun 26, 2026
07:28
Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
Published on: November 27, 2015
Bases for Understanding Polymerization under Pressure: The Practical Case of CO2
J Contreras-García1, A Martín-Pendás, B Silvi
1Departamento de Química Física y Analítica, Universidad de Oviedo, E-33006 Oviedo, Spain.
The Journal of Physical Chemistry. B
|January 9, 2009
Summary
We developed a new method to track chemical bond changes in solids using electronic structure. This approach reveals how bonds reorganize under high pressure, specifically in carbon dioxide polymerization.
Area of Science:
- Solid-state chemistry
- Materials science
- Computational chemistry
Background:
- Understanding chemical bonding transformations in solids is crucial for predicting material properties.
- High pressure significantly alters molecular solids, leading to complex bond reorganizations.
- Previous methods lacked unambiguous characterization of long-range interactions and bond formation.
Purpose of the Study:
- To present a novel quantitative strategy for monitoring chemical bonding transformations in solids.
- To characterize long-range interactions and bond formation using electronic structure topology.
- To apply this strategy to understand controversial aspects of carbon dioxide polymerization under pressure.
Main Methods:
- Utilizing the electron localization function (ELF) formalism.
- Analyzing the topology of the electronic structure.
- Quantifying charge flux between electron localization regions.
- Investigating the polymerization of carbon dioxide (CO2) under high pressure.
Main Results:
- The developed strategy unambiguously characterizes interactions and bond formation.
- Charge flux analysis identifies the nature of interactions between chemical entities.
- In CO2 polymerization, a synchronic weakening of the intramolecular C==O double bond and formation of a new intermolecular C--O bond were observed.
- The bonding network topology in pseudopolymeric phases indicates incipient new bond formation in higher-pressure polymers.
Conclusions:
- The new quantitative strategy effectively monitors chemical bonding transformations in solids.
- The study confirms a specific bond reorganization mechanism in CO2 polymerization under pressure.
- This analysis can predict coordination in high-pressure phases, aiding experimental synthesis and structure indexing.
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