ISSN:
0098-1273
Keywords:
Physics
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
A thermally reversible crystal transition was found for γ-helical poly(γ-n-alkyl L-glutamate)s (alkyl = ethyl, propyl, butyl, and amyl). The transition temperature is higher than that of the side-chain mechanical dispersion, and decreases from 115 to -5°C, as the alkyl groups become longer. The transition in poly(γ-n-propyl L-glutamate) is clearly first order. The structures were analyzed by x-ray diffraction at various temperatures. It is noteworthy that the pseudohexagonal form observed below the transition temperature is less ordered than the hexagonal form at higher temperatures. The mechanism of this transition is discussed.
Additional Material:
9 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pol.1979.180170508
