02093nas a2200241   4500008004100000022001400041245014100055210006900196260008700265300001200352490000700364520116000371653002201531653001501553653001501568653002601583653003101609653003601640100001801676700001701694700001801711856012201729       2005                        eng d  a0892-705700aDurability of natural fiber-reinforced composites of ethylene-propylene copolymer under accelerated weathering and composting conditions0 aDurability of natural fiberreinforced composites of ethyleneprop  a1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLANDbSAGE PUBLICATIONS LTDcNOV  a489-5080 v183 a<p>Three types of composites are prepared by the melt mixing of ethylene-propylene copolymer (EPC) with (i) 3 % NaOH-treated jute fiber, (ii) 17.5 % NaOH-treated jute fiber, and (iii) commercial microcrystal line cellulose powder using maleated EPC as compatibilizer. The composites obtained are characterized by FTIR and microscopic measurements. Their mechanical properties are measured using a UTM (Instron model 4204). The durability of the composites is evaluated in an irradiation chamber with UV radiation of wavelength lambda &gt;= 290 mn and composting conditions at different time intervals. The composites made from microcrystalline cellulose show superior mechanical properties, biodisintegrability, as well as photoresistance whereas the specimen containing 3% NaOH-treated fiber exhibited the lowest photoresistance. Increasing the quantity of maleated EP (MEP) in the composition decreases photostability. Neat EPC has been found to be highly stable than all the composites with increasing UV irradiation. It has been found that the composites are less durable under both abiotic and biotic conditions in comparison to the neat polymer.</p>10acompatibilization10acomposites10ajute fiber10amechanical properties10aMicrocrystalline cellulose10aphotodegradation and composting1 aKumar, A., P.1 aDepan, Dilip1 aSingh, R., P.  uhttp://library.ncl.res.in/content/durability-natural-fiber-reinforced-composites-ethylene-propylene-copolymer-under-002004nas a2200253   4500008004100000022001400041245011800055210006900173260009900242300001200341490000700353520106500360653001801425653001401443653002001457653002601477653001501503653001801518100002601536700002001562700001901582700001801601856013101619       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.  uhttp://library.ncl.res.in/content/effect-gamma-dose-rate-crystallinity-and-morphological-changes-gamma-sterilized-biomedical-0