Preparation And Characterization Of UV Isolated Microcapsules Prepared By Emulsion Polymerization

In this paper, the PMMA/OMC ultraviolet isolated microcapsules were prepared by emulsion polymerization with the use of PMMA as the core material and OMC as the core material. The effects of emulsifying agent, emulsifier type, HLB value of emulsifier, dosage of emulsifier, concentration of system, core wall ratio, initiator type, dosage of initiator, dosage of crosslinking agent, stirring speed and other factors on the properties of microcapsules were systematically evaluated. Biological microscope, SEM, NMR, UV-Vis, thermal gravimetric analyzer (TGA) were used to characterize the morphology, structure, absorbance and embedding rate of microcapsules. The results show that the optimum conditions for the preparation of nanocapsules were:Span-80/Tween-80 as emulsifiers, the HLB value is 11, emulsifying time is 0.5h, emulsifier dosage is 6%,5% azo different nitrile (AIBN) as initiator, core wall ratio of 2:1, the amount of crosslinking agent pentaerythritol tetraacrylate (Petra) is 25%. The microcapsules were spherical and compact, the size of the microcapsules was about 200nm, the embedding rate was 60%, with a heat resistant temperature of 170?The PMMA/OMC ultraviolet isolated microcapsules were prepared by the suspension polymerization of styrene maleic anhydride copolymer (SMA) as dispersant and OP-10. The effects of the dosage of dispersant, OP-10 and SMA were investigated. The results show that the optimum conditions for the preparation of microcapsules were:SMA:OP-10=18:5,the mixing rate were 800-1200rpm, the embedding rate reached 63%, the particle size was 200-10 m, and the heat resistance temperature reached 170?. The average particle size of microcapsules is 200nm, the surface is smooth and dense, and the particle size is uniform. In this paper, we have prepared a high embedding rate of ultraviolet micro capsule, which can extend the application of microcapsule.