Screening Preparation And Characterization Of Poly (Methyl Methacrylate) Microspheres Containing Chemical Sunscreens

In this paper,polymethyl methacrylate(PMMA)is used as the wall material,Octylmethoxycinnamate(MC80)as the core material,and the sunscreen particle microspheres of polymethyl methacrylate containing Octylmethoxycinnamate were synthesized by emulsion polymerization.A series of studies on the content of emulsifier,reaction temperature,homogenization speed and stirring speed were carried out.The embedding rate,particle size and morphology of polymer microspheres and their application in sunscreen products and SPF value were investigated.The results showed that PMMA-MC80 sunscreen particles were better prepared with a core-wall ratio of 1:2,an emulsifier content of0.25%,a temperature of 30?,and an initiator concentration of 0.15%.The mass velocity was19,000 rpm and the stirring rate was 150r/min.The PMMA-MC80 sunscreen particles prepared under optimal conditions were characterized by an embedding rate of 28.4%,a particle diameter of 1000 nm,a regular spherical shape,and an SPF value of 10.54 and the SPF value of the unembedded Octylmethoxycinnamate sunscreen cream at the same concentration of Octylmethoxycinnamate was increased by 82.04%.This indicates that the sunscreen ability of the encapsulated MC80 is significantly improved.After the combination of octyl methoxycinnamate particles and avobenzone,the decrease rate of SPF value decreased from 57.48% to 25.05%,and the decrease rate of PA decreased from 67.8% to24.86%,indicating that the compatibility of octyl methoxycinnamate is greatly enhanced.