Abstract:

The effects of emulsifiers and thickeners on low-viscosity liquid crystal emulsions and their liquid crystal and ejection in binary aerosol propellants were studied, then the stability and ejection and liquid crystal of the low-viscosity emulsions were monitored by investigating their emulsifiers and thickener. Glycoside emulsifiers, alcohol ester emulsifiers and polyglycerol emulsifiers （single use and mixed use） were used to study their effects on emulsion viscosity and liquid crystal. Xanthan gum, Carbomer, Acrylates/Beheneth-25 Methacrylate Copolymer, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, and their combinations were used to study the effects on viscosity, the stability and ejection state of the emulsions. The results show that polyglycerol emulsifier is suitable for low-viscosity liquid crystal emulsions, in addition, it is more easily to pump out in binary aerosol propellants with large opening angle. The open angle of low-viscosity emulsions in binary aerosol propellants is wider when the viscosity is lower, however, it is very difficult to prepare low viscosity emulsions with good high temperature stability as well as excellent centrifugal stability. Thickeners play a very important role in stability. Low-viscosity and stable emulsions can be prepared by Acrylates/C10-30 Alkyl Acrylate Crosspolymer combined with Xanthan gum. The liquid crystal emulsions have smaller particle size with compounding emulsifier and the formation of liquid crystals is beneficial to the stability of emulsions. When the low viscosity liquid crystal emulsion is applied to the body, the moisture content increases significantly, and the transepidermis water loss （TEWL） decreases significantly, which proves that the emulsion has good moisturizing and repairing effects.

Key words: liquid crystal emulsion, low-viscosity emulsions, stability, Ejection test