Core-Shell polymers of silicone dioxide-styrene system were prepared by sequential emulsion polymerization. In inorganic/organic Core-Shell composite particle polymerization, silicone dioxide adsorbed by surfactant sodium dioctyl sulfosuccinate (EU-DO133L) was prepared initially and then core silicone dioxide was encapsulated emulsion by sequential emulsion polymerization using styrene at the addition of potassium persulfate (KPS) as an initiator. We found that SiO2 core shell of SiO2/styrene structure was formed when polymerization of styrene was conducted on the surface of SiO2 particles, and the concentration sodium dioctyl sulfosuccinate (EU-DO133L) was 0.5~2.0g. The structure of core-shell polymer were investigated by measuring to the thermal decomposition of polymer composite using thermogravimetric analyzer and morphology of latex by scanning electron microscope(SEM).
Silicone surfactants are widely used in many industrial area because of its thermal stability and lower foaming property. But it has limitation to expand the application because of migration and bubble generation issues when it is mixed with organic surfactant. In this study, epoxy functionalized fluoro-silicone surfactant, perfluoro glycidoxypropyl polyether siloxane(PFGES), was synthesized using hydrosilylation reaction among perfluoro methyl hydrogen siloxane, allyl glycidyl ether, and allyl ployether in order to get lower surface tension, better thermal stability than conventional silicone surfactant, and reactivity with anhydride function.
The hydrosilylation is an addition reaction of Si-H bond to unsaturated double bonds, which provides a convenient mechanism to synthesize poly(dimethylsiloxane-co-methylsiloxane)copolymer having siloxy units in polymer backbone. In this study, Poly(dimethylsiloxane-co-methylsiloxane) copolymer was synthesized through the polymerization reaction of cyclopentasiloxane with poly(methyl-hydrogen) siloxane. Silicone-hydrogen functional group of the poly(dimethylsiloxane-co-methylsiloxane) copolymer was substituted to the alkyl groups by hydrosilylation. And their structure was analyzed with FT-IR, H-NMR and GPC instruments, respectively. Surface tension of the synthetic compounds is increased from 22dyne/cm to 25dyne/cm according to increase additional EO moles. The cmc which was evaluated by surface tension was ranged 10-5 to 10-4mol/L and it was decreased according to increase of dimethyl siloxyl content. HLB number of these surfactants was evaluated 9.5 to 11.5 range. These silicone surfactants is applied to self-emulsifier defoamer and personal care products as surface tension depressant, emulsifier, foam control agent.
Liquid crystal (LC) system was introduced into W/O emulsion in order to enhance the stability and moisturizing effect. The LC system, composed of beeswax, surfactant, and water was formed on the surface of emulsion droplet, which was investigated through a polarized microscope. The phenomenon that the viscosity in W/O emulsion system is decreased with time, was reduced by the formation of LC with the addition of beeswax. Centrifugal separation test showed that the stability of emulsion system was increased with the addition of beeswax to 3%. The color change of vitamin C was delayed in LC emulsion systems, which indicates stabilization effect against the oxidation of vitamin C. Evaporation rate in W/O emulsion was retarded by LC, so that high moisturizing effect is expected in W/O LC system.