【摘要】 非晶PET等温结晶后,用DSC、WAXD、SAXS、密度和透射电镜等方法,考察了结晶PET在升温过程中的结构变化,进一步证实了过程中发生部分熔融再结晶;同时形态也起了明显变化:片晶增厚,片晶侧向尺寸增大,由节瘤状晶粒堆砌部分地转变为典型的片晶堆砌,构成片晶的微晶尺寸增大,晶体趋于完善,折迭表面的规则折迭增加。这样,在等温结晶时生成的结构状态转变为更稳定的形态,因而相应地在DSC曲线上出现两个熔融峰。更多还原

【Abstract】 The structure change of crystalline PET, which were crystallized from amorphous species isothermally at various temperatures, was investigated in the course of temperature elavation by means of DSC, WAXD, SAXS, density measurement and TEM The result shows that besides there are partial melting and recrystallization in the process, its morphology is modified at the same time invluding the thickening and enlargement of lamella, crystals changing from nodular packing to typical lamella packing, enlargement and perfection of the crystallite and increasing of regular folding on fold surface. Thus, the morphology formed at isothermal crystallization turns to be more stable which is the cause of the appearence of double melting peaks on DSC curves.更多还原