Study On Stabilization Of Non-Aqueous Foam With Special Surfactants

Non-aqueous phase foams are widely used in daily cosmetics,food processing,petrochemicals and porous functional materials.However,conventional surfactants have difficulty in foaming in non-aqueous phase solvents.Therefore,this paper investigates the effect of special surfactants on the foaming performance of non-aqueous phase solvents,mainly by selecting eight special surfactants and solvents with different polarity: water,methanol,formamide,ethanol,acetone,ethyl acetate,benzyl acetate,toluene,cyclohexane and decane.The whole paper analyzed the effects of solubility,liquid phase viscosity and surface tension on the foaming performance of non-aqueous surfactant solutions from the solution performance of special surfactants in non-aqueous phase solvents,and studied the foaming performance of special surfactants in different polarity solvents,and stabilized the non-aqueous phase foams with special surfactants by observing the foaming volume,half-life of discharge and microstructure of foams formed in non-aqueous phase foams.foam was systematically investigated,and the experiments led to the following conclusions:(1)The effects of the solubility properties and surface activity of the solution system on the formation and stability of the foam were analyzed.The solution system showed an overall trend of increasing liquid phase viscosity,and its liquid phase viscosity in formamide ranged from 3.845 to 3.958 m Pa·s,which indicated that the dissolution performance of the special surfactant in solvents of different polarities was better.The surface tension of the solution system showed a trend of decreasing and then increasing with the increase of the special surfactant concentration,and its surface tension value in the non-aqueous phase solvent formamide was the largest compared with other solvents,ranging from 43.326 m N/m to 49.026 m N/m.(2)The foaming properties of the foaming agents were analyzed and preferentially selected.The systems of ethoxystearyl alcohol C18E9,fluorocarbon surfactant FC-170 C,polydimethylsiloxane PDMS,Ethanediyl dioctadecyl dimethyl ammonium bromide DDAB,sodium lauryl glutamate LGS,coconut oil fatty acid monoethanolamide CMEA,tea saponin TS and cocamidopropyl hydroxysulfonyl betaine CHSB,The stirring rate and stirring time were also preferentially selected,and the foaming performance of the solution system was optimized when the stirring rate and stirring time were controlled at 8000 r/min and 90 s.(3)The influence law of the foaming performance of special surfactants in non-aqueous phase solvents with different polarities was revealed.The foaming performance of the solution system in strongly polar solvents was significantly higher than that in medium and weakly polar solvents,and there existed a range of foam gas content and discharge half-life of the solution system from in weakly polar solvents to strongly polar solvents,respectively.The foaming performance and foam stability of the solution systems were optimized when the concentration of the specialty surfactants was 0.5 wt% or 0.7 wt%.In formamide,the bubbles formed in FC-170 C,PDMS,DDAB,CMEA and CHSB were more closely arranged and the bubbles were more uniform in size,and the solution system showed stronger stability at this time.