02005nas a2200253   4500008004100000022001400041245011800055210006900173260009900242300001200341490000700353520106500360653001801425653001401443653002001457653002601477653001501503653001801518100002601536700002001562700001901582700001801601856013201619       2009                        eng d  a0141-391000aEffect of gamma-dose rate on crystallinity and morphological changes of gamma-sterilized biomedical polypropylene0 aEffect of gammadose rate on crystallinity and morphological chan  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLANDbELSEVIER SCI LTDcFEB  a272-2770 v943 a<p>The present work is aimed to study the changes in crystallinity and morphology of biomedical polyolefins after gamma-sterilization. The isotactic polypropylene (iPP) films were sterilized by gamma-radiation and the changes were characterized by differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD) and atomic force microscopy (AFM) techniques. The effect of dose rate on crystallinity changes also was focused. It was found that crystallinity and morphology significantly changed with gamma-irradiation. There was an increase in crystallinity Lip to 10 kGy accompanied with decrease in viscosity and mechanical properties. The changes in crystallinity mainly depend on gamma-irradiation dose and dose rate. The rise in crystallinity was attributed to chain scission and forming new perfect lamellae. However, the reduction was accompanied by occurrence of gamma- and beta-phases and crosslinking. Possible explanations for transitions in phases are also discussed based on our results. (C) 2008 Elsevier Ltd. All rights reserved.</p>10aCrystallinity10aDose rate10aGamma radiation10amechanical properties10aMorphology10apolypropylene1 aAlariqi, Sameh, A. S.1 aKumar, Pratheep1 aRao, B., S. M.1 aSingh, R., P.  uhttps://library.ncl.res.in/content/effect-gamma-dose-rate-crystallinity-and-morphological-changes-gamma-sterilized-biomedical-0