In this study for the first time, 1-methylimidazole was microencapsulated successfully by using solid epoxy resin via solvent evaporation method. Fourier transform infrared spectroscopy, scanning electron microscopy, thermal gravimetric and differential scanning calorimetry were used for characterization of microcapsules and epoxy resin/microcapsules systems. The results revealed that although the solid epoxy shell was in contact with imidazole curing agent for long time, it was still thermoplastic. Only likely anionic polymerization increased the chain length of solid epoxy resin so that its melting temperature is increased from 64 to 78 oC. On the other hand all the epoxy functional groups of the microcapsule’s shell do not participate in the curing reaction with the core curing agent. Results have shown that by increasing the residence time of the microcapsules in the contact with the epoxy resin matrix, epoxy groups of liquid epoxy decreased slightly but the rate of increasing in the complex viscosity or the rate of curing are increased and the cured epoxy system becomes single-phase. On the other hand, in the presence of microcapsules the curing reaction of epoxy resin systems was done successfully and long time exposure of epoxy/microcapsules nearly did not affect on the curing temperature and the onset of increasing viscosity or gel time at 120 oC.
کلید واژگان :Methylimidazole . Microencapsulation . Epoxy resin . Solid epoxy shell . Curing agent
ارزش ریالی : 600000 ریال
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