乙酰丙酮金属络合物对酸酐固化环氧树脂体系潜伏性促进作用的研究

A transition metal acetylacetone was studied as latent accelerator in the curing of anhydride cured epoxy resin by DSC, TEA, and rotation viscometer technique. The results reveal that the metal acetylacetone serves as an latent accelerator for anhydride curable epoxy resin system, and the rate of curing is found to increase with enhanced concentrations of the metal chelate. The system provides very fast gel time at 160-180℃ and combined with very good storage stability (> two months). Curing kinetic studies reveal that the overall suring process follows first order kinetics. The electrical,mechanical and thermal properties of cured com-pound of epoxy resin system catalyzed by the M_T(acac)_n and BDMA accelerator and cured by anhydride was also studied and compared in this paper.     

端羟丁腈聚氨酯/聚甲基丙烯酸甲酯互穿网络高聚物的T_g和形态研究——Ⅱ.化学相容性的影响

用动态力学和透射电镜的方法,研究了化学相容性对丁腈羟聚氨酯/聚甲基丙烯酸甲酯互穿网络高聚物[PU(HTBN)/PMMA-IPN]的T_g转变行为和形态的影响。适当地提高端羟丁腈(HTBN)中氰基含量或加入合适的链延伸剂或共聚单体,可得到半相容的体系。丙烯腈含量为24.3％时,相区尺寸约为200?,在—20—+130℃范围内的Tanδ值均在0.2—0.3。由于极性基的相互作用,聚氯醚聚氨酯[PU(PCE)]/PMMA IPN具有更微细的相结构及单一的T_g转变,其Tanδ峰值为1.6。     

乙酰丙酮金属络合物对酸酐固化环氧树脂体系潜伏性促进作用的研究

酸酐固化环氧树脂体系比胺固化的体系具有更优异的力学和电气性能以及高温热稳定性能,但需要较高和较长的固化温度和时间。尽管在室温下有一定的使用期,为了节红能源和缩短生产周期,通常用叔胺类促进剂加快其固化反应速率,但此时体系的使用期较短。因此研制一种能用于酸酐固化环氧树脂体系的潜伏性促进剂是十分必要的。理想的潜伏性促进剂应使其在室温下的贮存使用期不受影响,且在一定的温度下具有较快的固化反应速率,此外,固化产物应具有良好的机电热性能。