The thermal stability of latent resin systems, cycloaliphatic epoxy/4,4＇- dihydroxydiphenylsulfone/aluminum complexes, was investigated by dynamic differential scanning calorimetry （DSC） analysis. Experiments were conducted under non-isothermal condition in a nitrogen atmosphere at the heating rate of 10, 20, 30 and 40 ℃/min, respectively. TG curves showed that, in the temperature range of 25 to 600 ℃, the stability of the resin systems could be enhanced by increasing the length of the aliphatic chain in the initiator. Both the Kissinger method and the Ozawa-Flyrm-Wall method were employed to calculate activation energies of the decomposition reaction, and the values obtained from the two methods were compared. Moreover, the corresponding reaction mechanism was identified by the Achar differential method and the Coats- Redfem integral method. The experimental results showed that these four methods were reliable and effective to study the kinetics of the thermal decomposition reaction; and the most probable thermal decomposition mechanism of the resin systems we proposed was found to comply with Mampel power law （m=1）.
One chemical approach using nitric acid as the solvent to decompose thermosetting epoxy resin was discussed. The samples were prepared by using different kinds of curing agents, namely polyamide (PA651), isophorone diamine (IPDA), 4,4'-diaminodiphenylmethane (DDM) and 2-ethyl-4-methy-imidazole (EMI-2,4) and different kinds of epoxy resins, namely bisphenol-A epoxy resin(E-44), bisphenol-A epoxy resin(E-51), N,N,N',N' teraglycidy 4,4' diaminodiphenyl methane (AG-80) and diglycidyl-4,5-epoxycyclohexane-1,2-dicarboxylate (TDE-85). Their effects on decomposition rate were investigated and the decomposition products were analyzed by Infra-red (IR) spectra, and Gas Chromatography-Mass Spectrometry (GC-MS). Based on conclusions drawn from experiments, the mechanism of degrading thermosetting epoxy resin with nitric acid was envisaged tentatively.
