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The Brill Transition in Transcrystalline Nylon-66

2006; American Chemical Society; Volume: 39; Issue: 13 Linguagem: Inglês

10.1021/ma060487h

1520-5835

Alexander Y. Feldman, Ellen Wachtel, G. Vaughan, A.F. Weinberg, G. Marom,

biodegradable polymer synthesis and properties

The Brill transition in transcrystalline nylon-66 occurs at a temperature that is 15 K higher than in the parent spherulitic nylon-66. This difference is assigned to the high level of crystalline orientation and chain packing order in the former. The similarity of the influence of the orientated morphology on the Brill transition and on the glass transition is pointed out, suggesting that the Brill transition, which is inherently a first-order process, comprises a second-order element. Utilizing the brightness of the synchrotron microbeam WAXD to make in situ diffraction measurements during relatively rapid heating and by running two consecutive cycles at different heating rates, the activation energy for the Brill process is derived for the first time. The values of 77 and 28 kJ/mol are calculated for transcrystalline and spherulitic nylon-66, respectively.