中文摘要：

微波辅助合成了具有超分散稳定作用，且可作为纳米银前驱体的油溶性羧酸银；在80℃下，在环氧树脂介质中，以乙醛为还原剂原位构筑了纳米银（n-Ag），进而制备了纳米银环氧树脂复合材料；用冷冻蚀刻电镜、离心实验对分散系进行了表征和评价；测试了原位构筑n-Ag和添加分散n—Ag对环氧树脂复合材料的力学性能。结果表明：原位构筑的银为30nm的粒状颗粒，大小均匀，在介质中无团聚行为；n—Ag分散系经72h普通离心和56h非连续超离心均未发生沉降，表现出理想的分散稳定性，n-Ag对环氧树脂有显著地增韧改性作用，但原位构筑的n—Ag其增韧改性效果明显好于添加的n—Ag。当原位构筑的n-Ag含量为2．0％-2．5％时，增韧改性效果最佳，此时，复合材料的拉伸强度、抗冲击强度、断裂伸长率可分别提高80%～90％、100％和110％～130％。

英文摘要：

The oil-soluble sliver salt which could been used as hyper-disperston stabilizer ann precursor synthesiing nano-Ag was synthesized by microwave irradiation. The sliver nanoparticles （n-Ag） were synthesized in-situ in epoxy resin by liquid reduction with acetaldehyde at 80℃. The diameter, diameter distribution and con- glomeration behavior of n-Ag in dispersion were observed by freeze-etching replication transmission electron microscopy（FRTEM）. Formation and dispersion stability mechanism of n-Ag were explained. The tests of normal centrifuge and high speed centrifuge were used for evaluating the dispersion and dispersion stability of n-Ag. Influences of n-Ag modifier of different acquisition methods（through in-situ synthesizing method or adding meth- od） on mechanical properties of epoxy resins composites were measured by mechanical test. The results show that n-Ag is composed of spherical particles with an uniform and average size of 30nm. n-Ag dispersion can maintain stability, no sedimentation and no agglomeration in epoxy resin medium,and didn＇t come into being sedimentation through 72h centrifuge tests and 56 h intermittent high speed centrifuge tests, n-Ag has toughening function to epoxy resin, but toughening effect of ultradispersion-stability n-Ag synthesized in-stiu in epoxy resin is better the one of adding n-Ag. The toughening effect to epoxy resin is best when the mass ratio of ultradispersion-stability n-Ag of resin is 2% to 2. 5%. Under this situation, the tensile strength, compression strength and breaking elongation of composite material increased respectively by about 80%-90%, 100%, 110%-130% compared with unmodified resin.