Copolymerization of hexafluoropropylene and tetrafluoroethylene: Effect on chain conformation and crystal structure
β Scribed by M. L. White; A. J. Waddon; E. D. T. Atkins; R. J. Farris
- Publisher
- John Wiley and Sons
- Year
- 1998
- Tongue
- English
- Weight
- 157 KB
- Volume
- 36
- Category
- Article
- ISSN
- 0887-6266
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β¦ Synopsis
A series of new copolymers of tetrafluoroethylene (TFE) and hexafluoropropylene (HFP) containing up to 50 mol % of the hexafluoropropylene comonomer have been investigated with respect to chain conformation and crystal structure using wide-angle X-ray diffraction (WAXD). Increasing HFP content leads to significant departures from the highly ordered crystalline structure of the homopolymer PTFE; the helical conformation of the chain relaxes and untwists to accommodate the larger OCF 3 pendant group in the HFP unit. Simultaneously the lateral hexagonal packing of the helices becomes less ordered and the a-dimension of the hexagonal cell increases. The above effects are progressive with increasing HFP content. At 50 mol % HFP incorporation the structure is a disordered crystalline phase.
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