| Heat resistant and high performance epoxy resins are important materials and develope with the progress of aeronautics and asronautics and many other technology fields. As a matrix of heat resistant composites, epoxy resin must be heat resistant so as to ensure the good performance at high temperatures.Hea-t resistance modification and novel curing agents of epoxy resin are the"focused"research field.Studies on the synthesis of amine curing agent containing benzoxzole, i.e., 2,6-diaminebenzobisoxazole (DIABO) and 4-aminebenzoxazole aniline (ABO) were carried, and the optimum parameters were determined. The structures were characterized with Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR), element analysis and other methods. The results showed that the curing agents had the pre-designed structures. Meanwhile the synthesis process of diglycidyl amine epoxy resin containing benzoxzole, i.e., aminebenzoxazole aniline epoxy resin (TGABO) was preliminarly studied and the structure was studied by FTIR. The results indicated that the structure of DIABO and ABO were plane and rigidity and the glass transition temperature of E/ABO system was 228 oC calculated by theoretical method.The curing process of various epoxy resins were determined by dynamic differential scanning calorimetry (DSC) .Bisphenol A diglycidyl ether (E) and 4,5-epoxycyclohexane diglycidyl ester (TDE) were used as epoxy resins and DIABO, mixture of DIABO and DDS, ABO were used as curing agents. The apparent kinetics of epoxy resin systems during curing were studied by Kissinger and Ozawa and Crane methods, respectively. Curing reaction mechanism of E/ABO was determined combined with FTIR and it meeted with n-order reaction kinetics model. Glass transition temperature was determined by torsion braid analysis (TBA). The results showed that glass transition temperature could be improved by adding DIABO or ABO as curing agents. Various factors which affected heat resistant including ratio and curing time and cured temperature were also discussed based on the results of thermogravimetric analysis (TG). The results indicated that the char yield was increased by adding DIABO.The kinetic parameters of cured epoxy resin systems were determined by using Kissinger and Flynn-Wall-Ozawa and Friedman methods. According to the value of activation energy obtained, Coats-Redfern and Master-Curves methods were used to discuss the solid-state decomposition mechanism. It was found that the solid-state decomposition mechanism of E/DIABO/DDS followed phase boundary controlled reaction (Rn, n=0) at the first stage and random nucleation with two nucleus on the individual particle (F2) at the second stage. Solid-state decomposition mechanism of TDE/DIABO/DDS was corresponded to nucleation and growth (JMA). The solid-state decomposition mechanism of E/ABO followed JMA at the first stage and random nucleation with three nucleuses on the individual particle (F3) at the second stage.According to the results of tensile, flexural, Al-Al signal adhesive properties and scanning electron microscopy (SEM) torography of bend fracture surface, the effects of DIABO contents on properties were discussed. The results showed that the properties were increased with DIABO content, and the best DIABO content was 2mass% at room temperature. The best DIABO content was 4mass% while maintaining 15 minutes at 180oC. Corresponding to TDE system, adhesive property and flexural modulus were raised and the flexural strength was decreased followed by adding DIABO. Dynamic mechanical analysis (DMA) and hygroscopicity test were also used to investigate the properties of cured resins. The effect of DIABO content on epoxy/PBO microcomposite interfacial shear strength (IFSS) was also discussed based on the results of signal fiber pulled-out test. It showed that the value of IFSS was increased by adding DIABO. The properties of E/ABO were also discussed. E / ABO system had higher Tg (Tg = 210°C) and better mechanical properties (σf = 100.56MPa)...
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