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Systematic studies of morphological changes of precision polyethylene
Chip S Few1, Kenneth B Wagener1, Donovan L Thompson1
1The George and Josephine Butler Polymer Research Laboratory, Department of Chemistry, University of Florida, Gainesville, Florida, 32611-7200, USA.
Macromolecular Rapid Communications
|December 10, 2013
Summary
Polyethylene
Area of Science:
- Polymer Science
- Materials Science
- Organic Chemistry
Background:
- Polyethylene morphology is crucial for its properties.
- Precisely spaced defects can influence polymer structure.
- Understanding defect effects aids in designing advanced polyethylenes.
Purpose of the Study:
- To review morphological changes in polyethylenes with controlled defects.
- To analyze the impact of defect characteristics on crystallization.
- To differentiate effects in functionalized vs. branched polyethylenes.
Main Methods:
- Acyclic diene metathesis polymerization for defect introduction.
- Differential scanning calorimetry (DSC) for thermal analysis.
- X-ray scattering (wide-angle and small-angle) for structural data.
- Infrared spectroscopy for chemical characterization.
Main Results:
- Defect frequency, size, and functionality significantly alter crystallization and crystalline structure.
- Functionalized polyethylenes and those with alkyl branches exhibit distinct morphological responses.
- Detailed structural characterization provided insights into polymer chain packing and ordering.
Conclusions:
- Precisely spaced defects offer a powerful tool to control polyethylene morphology.
- Tailoring defect types and spacing allows for fine-tuning polymer properties.
- This review highlights strategies for designing novel polyethylenes with desired characteristics.
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