摘要
以3,3’,4,4’-二苯甲酮四羧酸二酐(BTDA)和间苯二胺(m-PDA)为单体合成了聚酰胺酸。采用3种热酰亚胺化工艺对这种聚酰胺酸进行了处理:一步法溶液热酰亚胺化;涂膜快速升温热酰亚胺化;两步法涂膜热酰亚胺化,再进行溶胀后高温处理。通过这3种不同的热酰亚胺化工艺处理,分别得到了珊瑚形的半晶结构的聚酰亚胺粉末,聚酰亚胺的环带球晶以及具有低有序性的聚酰亚胺薄膜。通过X衍射、偏光显微镜对半晶粉末,环带球晶和具有低有序结构的薄膜进行了表征,初步研究了热酰亚胺化工艺对聚酰亚胺结晶形貌以及结晶度的影响。研究表明,一步法溶液热酰亚胺化所得的聚酰亚胺粉末结晶度为57%;涂膜快速升温热酰亚胺化制备的聚酰亚胺薄膜在偏光显微镜下除了具有传统的Maltese十字消光以外,还具有明暗相间的同心圆环;力学性能测试表明,具有低有序性的薄膜与无定型的薄膜相比,前者具有更高的拉伸强度和拉伸模量,拉伸强度提高了7.0%,模量提高了16.8%,同时断裂伸长率下降为原来的83.5%。
Poly（ amic acid） was prepared, using 3,3＇, 4,4＇ - benzophenone tetracarboxylic dianhydride and meta-phenylene diamine as monomers. Three imidization procedures were used in this work, which are imidization in PAA solution at 180 ℃ ,imidization of PAA coating film at 200 ℃ ,and swell of the PI films and then processed at 300 ℃ respectively. A high-crystalline polyimide powder with coral-like morphology, a polyimide banded spherulite and polyimide films with low-order aggregation structure were obtained through these imidization procedures, respectively. Wide angle X-ray diffraction and polarized optical microscopy（POM） were used to characterize these polyimides. The effects of imidization procedures on the aggregation structures and crystallinity of this kind of polyimide were studied. Studies showed that polyimide powder has a crystallinity of 57 % ; there are concentric rings as well as Maltese cross on the POM pattern of polyimide spherulite; compared with amorphous polyimide films, polyimide films with low-order aggregation structure have higher tensile strength and modulus, meanwhile, a lower elongation at break.
出处
《四川大学学报（工程科学版）》
EI
CAS
CSCD
北大核心
2005年第5期88-92,共5页
Journal of Sichuan University (Engineering Science Edition)
基金
国家自然科学基金重点资助项目(50433010)
关键词
聚酰亚胺
聚集态结构
结晶
酰亚胺化
有序结构
polyimide
aggreation structure
crystallization
imidization
order structure
