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چکیده
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The curing reaction kinetics of an epoxy based on the diglycidyl ether of bisphenol- A (DGEBA) with an aromatic diamine, 4,4'-oxydianiline (ODA), was studied using non-isothermal DSC and FTIR isothermal curing at 120, 135, 160, and 180ºC. In all cases, we have observed one exothermic peak during DSC scan up to 350ºC. Kinetic parameters such as activation energy (Ea), reaction order, and rate constant were calculated from data obtained from DSC and FTIR tests. The obtained Ea values were 61 and 64 kJ/mol in the dynamic DSC measurements using Kissinger and Ozawa methods, respectively and 36.7 kJ/mol in the isothermal FTIR measurements. Thermodynamic parameters (ΔH#, ΔS#, and ΔG#) were calculated for isothermal curing reaction. The value of ΔG# increased with increasing isothermal curing temperature. Water absorption properties of the cured samples were measured at different temperatures. The diffusion coefficient (D) was in the range of 1.6×10-12 – 7.1×10-12 m2/s from room temperature to 65ºC. The diffusion activation energy was found to be 26.8 kJ/mol.
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