聚四氟乙烯-丙烯酸辐射接枝共聚中盐酸效应的研究

<正> 聚四氟乙烯(以下简称F4)辐射接枝改进粘结性能是一种较好的方法,已有不少报道。七十年代初,已有聚烯烃等辐射接枝中酸效应的研究,表明无机酸能提高接枝速度。 众所周知,F4不耐高能射线,在通常条件下,很小的辐射剂量即引起它的物理机械

STUDIES OF THE EFFECT OF HYDROCHLORIC ACID ON THE RADIATION INDUCED GRAFT COPOLYMERIZATION OF ACRYLIC ACID TO POLYTETRAFLUOROETHYENE

By the direct radiation grafting technique, effects of hydrochloric acid on radiation induced graft copolymerization have been studied. The experimental results show that the presence of hydrochloric acid markedly enhanced the grafted amount of acrylic acid to polytetrafluoroethyene. From the cross section and surface of the grafted film and its thickness change, it is found that grafting takes place on the surface of poly-tetrofluoroethyene by the presence of hydrochloric acid. The reasons is that the presence of hydrochloric acid will promote existing hydrogen abstraction reactions from the grafted chains to give more grafting sites. The outer-most layer is the homopoly-mer of polyacrylic acid,which is linked by chemical bond with the grafted copolymer, hence its adhesiveness to epoxy resin becomes greater.