紫外线辐照对HDPE结晶结构及化学结构的影响

CRYSTALLINE AND CHEMICAL STRUCTURE DEVELOPMENT OF HDPE DURING ULTRAVIOLET IRRADIATION

采用ＤＳＣ、ＷＡＸＤ、元素分析、ＦＴ－ＩＲ、ＥＳＣＡ、ＧＰＣ、交联度和密度测定，研究了紫外线辐照下ＨＤＰＥ的结晶结构及化学结构变化。结果表明，紫外线辐照后，ＨＤＰＥ的熔融温度降低、熔融热焓升高、结晶度增大、晶胞结构未发生变化；ＨＤＰＥ分子链引入了ＣＯＯＨ、Ｃ＝Ｏ、Ｃ－Ｏ、ＯＯＨ、ＯＨ等含氧官能团，分子量降低，分子量分布加宽，基本无交联发生。

he crystalline and chemical structure development of HDPE during ultraviolet irradiation was studied through DSC, WAXD, elementary analysis, FTIR, ESCA, GPC, crosslinking and density measurement. The results show that with the time of irradiation, the melt temperature of HDPE is decreased, its crystallinity is increased. The crystallite structrue, however, remains unchanged. During ultraviolet irradiation, COOH, C=O, C-O, OOH, OH etc oxygencontaining groups are introduced to HDPE molecular chain, the molecular weight is decreased and its distribution is widened, no crosslinking structure is detected.