反应型有机修饰剂对环氧树脂/粘土纳米复合材料热/机械性能的影响

使带有环氧基团的三缩水甘油基对氨基苯酚(TGPAP)分别与溴代正丁烷(BB)、2-溴乙醇(BE)反应，合成了反应型粘土有机修饰剂溴化(正定烷基)双环氧基(4-环氧醚基)铵(TGPAPB)和溴化(2-羟乙基)双环氧基(4-环氧醚基)铵(TGPAPE)。用这两种修饰剂改性粘土，分别制备出具有相同反应官能团但与环氧树脂的相容性略有不同的两种有机化粘土(B-Clay和E-Clay)。再用“粘土淤浆复合法”制备出两种环氧树脂/粘土纳米复合材料，研究了两种反应型有机修饰剂对纳米复合材料的结构和性能的影响。结果表明：带有羟基的E-Clay以高度无规剥离形式均匀分布在环氧树脂基体中；而B-Clay则形成了无规剥离/插层混合结构。两种粘土均参与固化反应在环氧树脂基体和粘土片层间产生了较强的界面作用力，从而显著提高了纳米复合材料的拉伸强度。粘土质量分数为3%的两种纳米复合材料，其拉伸强度分别达到32.4 MPa(E-Clay)和28.0 MPa(B-Clay)，比对应的纯环氧树脂聚合物分别提高了76.47%和52.51%。同时，这两种纳米复合材料的玻璃化转变温度(T_g)也略有提高。

Effect of Reactive Organic Modifiers on Thermal/Mechanical Properties of Epoxy/Clay Nanocomposites

Two reactive organic modifiers were firstly synthesized by reaction of triglycidyl p-aminophenol (TGPAP) with bromo-n-butane (BB) and 2-bromoethanol (BE) respectively. By using the two modifiers, two different types of organic clays (B-Clay and E-Clay) with the same reactive functional groups but different in compatibility with epoxy were prepared. Epoxy/clay nanocomposites were then synthesized with the above two organoclay via "clay-slurry compounding method'. The effect of two reactive organic modifiers on the structure and thermal/mechanical properties of the nanocomposites was studied. It is shown that E-Clay gave a highly exfoliated structure in epoxy matrix because of its better compatible with epoxy pre-polymer, while B-Clay presented an exfoliated/intercalated mixed structure. Remarkable improvement in tensile strength and modulus were obtained for the nanocomposites due to the formation of strong interfacial bonding between epoxy matrix and clay layers, which derived from reactions of organic modifiers on the organoclay with curing agent during curing. For the nano-composite with incorporation of 3.0% clay, the tensile strength and modulus enhanced by 76.47% and 258% for E-Clay respectively, while that with B-Clay were 52.51% and 236.92%. Besides, the glass transition temperature (T_g) of the two type of nanocomposites was marginally improved relative to neat epoxy resin.