05 مهر 1400
علي يادگاري

علی یادگاری

مرتبه علمی: استادیار
نشانی: دانشکده مهندسی نفت، گاز و پتروشیمی - گروه مهندسی شیمی
تحصیلات: دکترای تخصصی / مهندسی پلیمر
تلفن: 07731222634
دانشکده: دانشکده مهندسی نفت، گاز و پتروشیمی

مشخصات پژوهش

عنوان Correlation of crystal alignment with interphase content in oriented high density polyethylene cast films
نوع پژوهش مقالات در نشریات
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مجله CRYSTENGCOMM
شناسه DOI
پژوهشگران علی یادگاری (نفر اول) ، جلیل مرشدیان (نفر دوم) ، حسین علی خنکدار (نفر سوم) ، Udo Wagenknecht (نفر چهارم) ، Gert Heinrich (نفر پنجم) ، Klaus-Jochen Eichhorn (نفر ششم به بعد) ، Mikhail Malanin (نفر ششم به بعد) ، Dieter Fischer (نفر ششم به بعد)

چکیده

The microstructure and crystalline morphology of high density polyethylene (HDPE) cast films prepared in a wide range of draw ratios (1.6 to 148.8) were investigated. The flow-induced orientation of crystalline and amorphous phases was characterized using Fourier transform infrared spectroscopy (FTIR). The results showed that the draw ratio has a crucial role on the orientation state of the cast films. Scanning electron microscopy (SEM) images also confirmed this influence. The crystallinity of the films was examined using both differential scanning calorimetry (DSC) and Raman spectroscopy. Moreover, considering a threephase structure (i.e. crystal, amorphous and interphase) for semi-crystalline polyethylene, Raman spectroscopy was also employed to estimate the amount of the so-called interphase in the HDPE cast films. As a result, the interphase content was found to decrease by increasing the applied draw ratio. The origin of this dependency was suggested to be due to a coil–stretch transition during elongation flow and the subsequent disentanglement. On the other hand, remarkable differences were observed in the CH2 bending vibration features of the Raman spectra of the cast films which were correlated with the applied draw ratios and with the calculated crystalline orientation functions.