سال انتشار: ۱۳۸۳

محل انتشار: نهمین کنگره ملی مهندسی شیمی ایران

تعداد صفحات: ۹

نویسنده(ها):

مصطفی رضایی – Polymer Engineering Group, Chemical Engineering Department, Engineering Faculty, Tarbiat Modarres University (TMU), 4838,Tehran, Iran
نادره گلشن ابراهیمی – Polymer Engineering Group, Chemical Engineering Department, Engineering Faculty, Tarbiat Modarres University (TMU), ,Tehran, Iran
Marianna Kontopoulou – Department of Chemical Engineering, Queen’s University, Kingston, Ontario, Canada K7L 3N6

چکیده:

Isothermal and nonisothermal crystallization kinetics of Ultra High Molecular Weight Polyethylene (UHMWPE) and its composite with 10 wt% Polyethylene Terephthalate (UHMWPE/10% PET composite) prepared with compression molding, were studied by differential scanning calorimetry. The Avrami equation was used to analyze the isothermal crystallization. Based on isothermal crystallization kinetics studies it was
suggested that crystallization of UHMWPE proceeds via heterogeneous nucleation and is governed by two-dimensional growth. The crystallization rates of the composites were lower than those of the neat material, whereas their ultimate crystallinities were higher. For nonisothermal crystallization studies, Avrami equation, Ozawa theory and combination of the Avrami and Ozawa equation were used. The values of these models were very scattered, because the nonisothermal crystallization is a dynamic crystallization and it cannot be predicted by these equations. The trend of crystallization rate and ultimate degree of crystallinity for UHMWPE and UHMWPE/10% PET in nonisothermal condition were the same as isothermal crystallization.