聚乙烯醇缩甲醛老化性能研究

STUDY ON THE HYGROTHERMAL AGEING TESTS OF POLYVINYL FORMAL

用红外光谱和其他测试方法对聚乙烯醇缩甲醛(PVFM)泡沫材料湿热老化前后力学性能、物理性能和化学结构的变化进行了研究。结果表明:①根据力学性能数据的分散性,PVFM泡沫材料质地上是不够均匀的;②经24h的湿热老化产生了严重的尺寸变化;③力学性能的下降是由于材料的吸湿性引起的;④化学结构的变化不是主链的断裂而是六元环的开环。

The changes in mechanical and physical properties and chemical structure of polyvinyl formal (PVFM) foam caused by hygrothermal ageing tests were studied by means of IR and other measuring methods. The results showed that PVFM foam was not sufficient homogeneous on the basis of the data discreteness of the mechanical properties; great dimensional changes have occured after 24 hours' hygrothermal ageing tests; the decrease of the mechanical properties were caused by the PVFM hygroscopicity; the structure changes were not the breaking of the main chain but the opening of the hexatomic ring.