کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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5186746 | 1502552 | 2008 | 5 صفحه PDF | دانلود رایگان |
The phase composition of ultra-high molecular weight polyethylene of two different molecular weights has been estimated using Raman spectroscopy. Materials have then been irradiated in air to give a received doses of 3.5 and 10Â Mrad, and crystallinity change with time has been monitored by differential scanning calorimetry (DSC), wide and small angle X-ray diffraction (WAX and SAX) and Raman spectroscopy. Analysis by DSC and X-ray diffraction involved melting and re-crystallisation. Raman spectroscopy demonstrated that the material consists of three phases, fully crystalline, fully amorphous and an intermediate all-trans non-crystalline phase. Following irradiation the mass fraction of this latter phase reduces as total crystal content increases. SAX results indicate a refinement of the original lamellae and the emergence of a population of smaller crystals. It is thought that the all-trans material exists as an interfacial phase and that scission within this phase facilitates the observed crystal changes.
Journal: Polymer - Volume 49, Issues 13â14, 23 June 2008, Pages 3111-3115