THE ORIENTATION AND CRYSTALLIZATION OF POLYETHYLENE TEREPHTHALATE

【摘要】 <正> The drawing behavior of three types of PET spherulites and PET amorphous samples have beenstudied. Two different sample preparation techniques were used in this study: (1) The films withnormal positive, normal negative or abnormal spherulites were prepared by solution casting tech-niques, then the films were deformed by uniaxial drawing. The uniaxial drawing behavior of PETspherulites appears to be dependent on the angles between the c-axis and the radius direction of thespherulites and that the deformation of spherulites becomes more difficult the larger the angles. (2)Amorphous films of PET were prepared first, then the films were deformed under uniaxial drawingto achieve c-axis orientation at a temperature near the glass transition temperature. The orientedfilms were subsequently annealed with fixed length at 215℃The films prepared in this way ex-hibit excellent c-axis orientation along the stretching direction. The degree of perfection of thecrystalline structure is much greater than that of the spherulites.更多还原

【Abstract】 The drawing behavior of three types of PET spherulites and PET amorphous samples have beenstudied. Two different sample preparation techniques were used in this study: (1) The films withnormal positive, normal negative or abnormal spherulites were prepared by solution casting tech-niques, then the films were deformed by uniaxial drawing. The uniaxial drawing behavior of PETspherulites appears to be dependent on the angles between the c-axis and the radius direction of thespherulites and that the deformation of spherulites becomes more difficult the larger the angles. (2)Amorphous films of PET were prepared first, then the films were deformed under uniaxial drawingto achieve c-axis orientation at a temperature near the glass transition temperature. The orientedfilms were subsequently annealed with fixed length at 215℃ The films prepared in this way ex-hibit excellent c-axis orientation along the stretching direction. The degree of perfection of thecrystalline structure is much greater than that of the spherulites.更多还原