✦ LIBER ✦

Physical aging in isotactic polypropylene

✍ Scribed by A. O. Ibhadon

Publisher: John Wiley and Sons
Year: 1996
Tongue: English
Weight: 250 KB
Volume: 62
Category: Article
ISSN: 0021-8995
DOI: 10.1002/(sici)1097-4628(19961212)62:11<1843::aid-app8>3.0.co;2-q

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✦ Synopsis

Physical aging studies were made using commercial and laboratory samples of isotactic polypropylene. Linear and nonlinear viscoelastic responses were measured after quenching the glass from above the glass transition temperatures to below the glass transition. Results show that aging is not eliminated by large mechanical deformations; rather, the time required for the glass to age into equilibrium is independent of the applied stress. Results obtained are purely kinetic and interpreted as the effects accompanying the process of glass formation in a semicrystalline polymer.

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