ISSN:
0360-6376
Keywords:
Physics
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
By using x-ray diffraction the total damage to a semicrystalline polymer is determined after exposure to high-energy ionizing radiation. By rearrangement of the first-order dependence of the fractional change in crystallinity on the dose the number of chemical and/or physical changes per 100 eV of energy absorbed [i.e., G(-units)] is computed. In the present effort on isotactic poly-(methyl methacrylate) (PMMA) the value of G(-units) ≈ 15 confirms previous results obtained by cryoscopy, and thereby yields a ratio of ca. 8:1 for chemical plus physical (i.e., total damage) versus chemical damage alone. From nuclear magnetic resonance (NMR) results, a partition of the physical damage into configurational and conformational changes yields G values of 6 and 7, respectively.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pol.1979.170171217
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