Abstract: Urea formaldehyde coated epoxy resin microcapsule was prepared.The effects of weight ration of core/shell materials and preparation condition on the performance of microcapsule were investigated.The healing process of microcapsule for epoxy resin matrix was studied.When the synthesis temperature of urea formaldehyde was 70oC and weight ratio of epoxy resin over benzyl alcohol was 10:3,weight ratio of core/shell materials was 0.8, and the amount of emulsifier was 5%~7%, the dispersing stirring speed was 500r/min,the obtained EP-UF microcapsule had an average particle size of 55μm with a good airtight property and high strength.When a higher coating ratio and a more flexible core was used, the microcapsule may reach higher tensile strength and higher healing rate.

Key words: microcapsule, urea formaldehyde, epoxy resin, self-healing, tensile strength, healing rate