安息香衍生物对LEPB丙烯酸羟基酯的光固化反应

通过ＤＳＣ法研究了大分子的丙烯酸酯化ＬＥＰＢ及其与三羟甲基丙烷三丙烯酸酯在不同安息香衍生物存在下的紫外光固化行为．通过诱导期与光强倒数的线性关系，光固化反应热等实验结果对不同光致引发体系进行了比较详细的讨论，并对安息香衍生物的引发效果进行评价，含ＤＭＰＡ２％的Ｂ体系在４．０６６×１０~－５／ｍ~２光强下．其聚合反应热焓为１５４．８Ｊ／ｇ．而将ＤＭＰＡ改换为安息香丁醚时．则同样的反应热焓要求光强达到８．０×１０~－５Ｗ／ｍ~２．因此，ＤＭＰＡ具有更好的引发活性．

Studies on photoinductive effects of benzoin derivatives upon acrylated LEPB

The effects of the presence of different benzoin derivatives upon the ultraviolet curing behaviors of acrylated I.EPB and of its mixtures with trihydroxymethylpropane triacrylate have been studied by DSC. Based upon the linear relationship between the photoinduction time and the reciprocal light intensity and upon the experimental results of the reaction enthalpy in the course of photocuring, the photoinductive effects of benzoin derivatives are compared. It is found that the polymer reaction enthalpyof System B with 2 % DMPA at a light intensity of 40. 66×10-5 W/m2 is 37 cal/g, whereas in the case of the same system with its DMPA replaced by benzoin-n-butylether, alight intensity of 80× 10-5 W/m2 is required by the equal amount of reaction enthalpy, afact which shows that DMPA has a higher photoinductive activity than benzoin-n-butylether .