Preparation of Polysulfide Rubber Microcapsules Based on Solvent Evaporation Method
Novel LPR@PS microcapsules were prepared by solvent evaporation method with polystyrene(PS)as shell material and liquid polysulfide rubber(LPR)as core material.The microcapsules of polysulfide rubber with different particle sizes,shell thickness,surface morphology and structure were designed by adjusting the factors of thermodynamic stability and dynamics of the microspheres.The influences of various process factors including type and usage of emulsifier,mass ratio of core to shell,stirring rate,oil/water volume ratio,reaction temperature and solvent were experimentally investigated.The structure and morphology of the prepared microcapsules were characterized by Fourier-transform infrared spectroscopy,optical microscopy,and scanning electron microscopy,respectively.The relative content of liquid polysulfide in microcapsules was determined by the content analysis of sulfhydryl group.The results indicate that the microcapsules with well-defined spherical shape and smooth surface were obtained after stirring at a rate of 500 r/min for 18 h at 20 ℃ with 1％sodium dodecyl sulfate(SDS)as emulsifier,m(core)∶m(shell)=4∶10,and the average particle size is 35.82 μm.The results of quantitative analysis show that the content of liquid polysulfide rubber in the microcapsules prepared under these conditions is 28.44％,and the encapsulation efficiency of the polysulfide rubber microcapsules prepared is 88.73％.The density of polysulfide rubber can be reduced by 19.86％.This study provides a new idea and technical support for the research and industrial application of the new generation of microcapsule based polysulfide rubber sealing materials.
万方数据
维普
