4号航空有机玻璃在大气老化中表面开裂的原因分析

AN ANALYSIS OF CRACKING OF AVIATION PERSPEX YB-4 DURING WEATHERING

本文用多种测试技术研究了YB-3和YB-4两种航空有机玻璃板材在结构和性能上的差别,以及它们在大气老化中对各种环境因素的敏感性。指出YB-4在大气老化中容易表面开裂的原因是:原始板材的分子量较低,分子量分布过宽;对氧和水较敏感。

The cracking phenomenon of aviation perspex YB-4 during weathering is discussed. Various techniques, such as GPC, TMA (Deformation-temperature) ,IR, ESGA, TG, DMA, stress-solvent crazing, and stress-strain testing have been employed to investigate and compare the structure and properties of perspex YB-4 and YB-3, and their changes in aging. The results show that the most important reasons that lead to relatively, easily cracking of YB-4 during weathering are the following; ( 1 ) The average molecular weight of original YB-4 is lower and its molecular weight distribution is wider. They are the inherent weaknesses of YB-4 in quality. ( 2 ) Oxygen and water, especially the latter, have more serious effects on YB-4 than on YB-3.