Research On The Synthesis Of Epoxy Resin Microcapsule Using For Self-healing

This essay introduces the survey of the technique and development of the microcapsule, which conclude and summarize the main function, the releasing mechanism, the compound raw material, the compound method structure and capability. It explains the principle of the self-healing of mechanism and influential the elements of the self-healing result, introduces the reseach and current situation on the domestic and international technique of the microcapsule's self-healing. The existing research indicate fully that the microcapsule technique has the greaty realistic sense to the materials'self-healing.This experiment adopted the in-situ polymerization, taking the formaldehyde and urea as the raw shell meterial, the E-51 as the core material and then synthesizing to gather the urea-formaldehyde to wrap and cover the E-51 microcapsule. It carries on the deeply study to the compound craft parameter and determines the optimum compound craft of the microcapsule. It use the surface features method of the metallargical microscopy, SEM, FTIR, TG/DTG, DTA etc to carry on the physical and chemical properties to superificial characteristic about the compound microcapsule's tdiameter of drain, the apparent appearance, the chemical stability and thermal stability etc.The research adopts the two-step method to sucessfully synthetize microcapsule. The first step is the addition reaction, taking the mol ratio of urea and formaldehyde as (1.5-2.0):1, the pH scales 7-9, the temperature of reaction tardy growing up from roomtemperature to 60-70 degree, and the reacting time 1h can acquire the colorless ropy water-soluble prepolymer; to use DBS as emulsion, then disperse E-51 to the surface of the water wrapping up oil; the second step is the condensation polymerization, mass ratio of core material to raw shell material, 0.8:1; the final pH value, 2.0; the reaction temperture, 70 degree; and the acidification time is 2-3h which can synthesize the better microcapsule products. In the process of the synthesizing microcapsule, the compound craft parameter has a great influence on microcapsule's properties.The microcapsule combined in the experiment has the good physical stability, through electronic microscope, one can catch sight of the regulation and density of the compound microcapsule form and regulation, and the surface is extraordinary density. According to the infrared spectrum analysis, the microcapsule compound in the experiment has proved to be successful. By microcapsule thermogravimetric analysis, the microcapsule combined in the experiment has been proved to have a good thermal stability.