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Irradiation of oriented LDPE films
Author(s) -
Nikolova M.,
Mateev M.
Publication year - 1991
Publication title -
journal of applied polymer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.575
H-Index - 166
eISSN - 1097-4628
pISSN - 0021-8995
DOI - 10.1002/app.1991.070430118
Subject(s) - crystallinity , low density polyethylene , irradiation , materials science , polyethylene , composite material , scattering , modulus , small angle x ray scattering , optics , nuclear physics , physics
Low‐density polyethylene (LDPE) films deformed uniaxially at 70°C and to low draw ratios have been irradiated on a 60 Co source with a dose rate of 0.33 Mrad/h in air. Their elastic modulus has been determined at room temperature and at 145°C, and their crystallinity has been studied by wide‐angle X‐ray scattering (WAXS). A two‐stage process has been proposed for the influence of irradiation on the structure and properties of the films. The first stage is characterized by enhanced chain scission in the strained regions, as a result of which structural reorganization takes place there and the crystallinity increases. This increase is greater for higher draw ratios and higher doses. The second stage is characterized by no structural changes in the material. The value of D , which separates the two stages, shifts toward higher doses for higher draw ratios. Under the conditions of the present experiment, the orientation of the films decreases the efficiency of network formation by the irradiation.