ISSN:
0098-1273
Keywords:
Physics
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
The polymorphism of isotactic poly(pentene-1) form I was studied by x-ray diffraction. Upon quenching from the melt at a temperature below 25°C, the films crystallized in a stable monoclinic form, which we have designated as form I (a = 22.4 ± 0.2 Å, b = 6.49 ± 0.05 Å, c = 21.2 ± 0.2 Å, β = 91 ± 1°). For higher quenching temperatures, a metastable form, form I′, appeared, which transforms to the normal modification upon aging (monoclinic, with: a = 24.3 ± 0.2 Å, b = 6.50 ± 0.05 Å, c = 19.3 ± 0.2 Å, β = 96 ± 2°). Both modifications have a 31 helical conformation. Limited changes in the packing mode could explain this polymorphism.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pol.1978.180160604
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