利用空间综合辐照地面模拟试验装置和热重分析、XPS分析等对空间近紫外辐射环境下均苯型聚酰亚胺(PI)薄膜力学性能演化的数学模型和物理模型进行了研究。研究发现,均苯型PI薄膜抗拉强度和断裂伸长率随着近紫外曝辐量的增加先降低而后呈现指数增加,最后趋于稳定。由热重分析和XPS分析可知,在近紫外辐照初期,C—O、C—C、C—N等价键的断裂是的导致其力学性能降低的主要原因,而后随着近紫外曝辐量的增加,不同分子链之间的交联是PI薄膜力学性能增加的主要原因。
The mechanical property and mechanism of polyimide film in near ultraviolet was studied and follow-ing results can be obtained:with the increasing of near ultraviolet,the rupture elongation and tensile strength of polyimide decrease firstly and then exponentially increase utile to stable.The breakage and cross linkage of molecular bond is the maj or cause of change of polyimide’s mechanical property in ultraviolet environments, and breakage of C—O,C—C,C—N is the major origin in early stage of irradiation and cross linkage is for the increase of mechanical property in subsequent ultraviolet irradiation.