二聚酸/月桂烯马来酸酐共聚酰胺的合成及性能研究

采用月桂烯马来酸酐(AMMA),二聚酸(DA)与三乙烯四胺(TETA)共聚缩合合成反应型共聚酰胺固化剂(CPA),并通过红外光谱和核磁共振氢谱进行表征。对其与市售品双酚A缩水甘油醚型环氧树脂(E-51)按等当量配比在不同温度下的凝胶时间、力学性能和耐热性能进行了测定。结果表明:综合考虑该新型共聚酰胺的黏度和性能,m(DA):m(AMMA)=7:3较为合适。与C36二聚酸型聚酰胺固化物的性能相比,采用Arrenhinus方程求出的E-51/共聚酰胺固化反应表观活化能(Ea)略低,固化反应活性略高; 在二聚酸中加入月桂烯马来酸酐能提高环氧固化物的网络交联密度及刚性,拉伸强度、拉伸模量、弯曲强度和压缩强度均有所提高,断裂伸长率虽下降23.2%,但仍能达到3.47%; 此外玻璃化转变温度(Tg)提高了38.8%,且在较高温度范围内(60～90℃)钢-钢剪切强度由13.92 MPa增加到21.68 MPa。该共聚酰胺固化物的综合性能更好,具有较好的市场应用前景。
The reactive copolyamide curing agent(CPA)was prepared from adduct of myrcene and maleic anhydride(AMMA), dimer acid(DA)and triethylenetetramine(TETA)by conventional polycondensation mechanism, and its structure was characterized by Fourier transform infrared spectroscopy(FT-IR)and 1H NMR. The gel times at different temperatures, mechanical properties and heat resistance property of commercial diglycidyl ether of bisphenol A epoxy resin(E-51)cured by CPA with equivalent molar ratio were investigated. The results showed that the optimal ratio of m(DA)to m(AMMA)was 7:3 when both viscosity and performance were considered. Compared with the properties of the cured product of commercial polyamide prepared from C36 dimer acid and TETA, the apparent activation energy(Ea)of E-51/CPA calculated by Arrenhinus equation was a little lower, and the curing reactivity was a little higher. In addition, the cross-link density and rigidity of the cured products of epoxy resin increased by the introduction of AMMA in DA during the preparation of copolyamide, and the tensile strength, tensile modulus, flexural strength and compressive strength all increased. The breaking elongation decreased by 23.2%, but it could still reach 3.47%. The glass transition temperature(Tg)increased by 38.8%, and in the higher range of temperature(60-90℃)the steel-steel shear strength increased from 13.92 MPa to 21.68 MPa. In a word, the E-51/CPA curing system has better comprehensive performance