Pyrolysis of Anionic and Thermally Prepared Polystyrenes
Leo A Wall1, Sidney Straus1, Roland E Florin1
1Institute for Materials Research, National Bureau of Standards, Washington, D.C. 20234.
Summary
This study details polystyrene molecular weight changes using thermal and anionic methods. A kinetic chain decomposition model explains the observed polymerization behaviors.
Area of Science:
- Polymer Chemistry
- Chemical Kinetics
Background:
- Understanding polymer molecular weight distribution is crucial for material properties.
- Previous studies on polystyrene synthesis lacked a comprehensive kinetic model.
Purpose of the Study:
- To investigate the molecular weight changes and initial rates of polystyrenes.
- To elucidate the underlying kinetic mechanisms in polystyrene preparation.
Main Methods:
- Preparation of polystyrenes via thermal and anionic polymerization techniques.
- Measurement of molecular weights, their distributions, and initial reaction rates.
Main Results:
- Observed changes in molecular weights and distributions were systematically recorded.
- Initial polymerization rates were quantified for both preparation methods.
Conclusions:
- A kinetic chain decomposition model effectively explains the experimental data.
- The model incorporates competing initiation, depropagation, transfer, and termination steps.
Keywords:
Anionic polystyrenemolecular weight distributionsmolecular weightspolymerspolystyrene degradationpyrolysisthermal polystyrenethermolysisMore Related Videos
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