Surface properties of water soluble surfactants,starch and their complexes by various methods

Surface,interfacial tensions and reduced viscosities were measured for water soluble surfactant and starch solutions in order to determine their potential as stabilisers,emulsifiers or cleansers. the surface tension and reduced viscosity for an acid hydrolysed starch (potato) initially were declined with concentration and then reached an equilibrium value of 56 mn/m and 3.1dm3/mol,at 20-40 wt.%. surface,interfacial tensions and reduced viscosity of starch with surfactant mixture using the ratio 40/60 decreased more rapidly with concentration reaching values of 41-44 mn/m,and 2.5dm 3/mol,respectively,at 40 wt.%. there was little dependence of surface or interfacial tensions on degree of substitution between 0.3-0.8 and amylose content of starch. surface and interfacial tensions for starch/surfactants mixtures were lower than those for only starch,particularly at lower concentrations. emulsions of soybean oil/water mixtures were successfully stabilised for >1 day by potato starch acetate/octenylsuccinate and acetate/dodecenylsuccinate but not by starch and surfactants. therefore,these starches may represent biodegradable,economically alternatives to some emulsifiers,soap or detergents filler with effective cleansing activity and coating polymers currently in use.