Synthesis And Properties Of A Series Of Betaines Surfactants

Molecular design of surfactant is the leading edge in the surfactant investigation. Theresearch and development of surfactant is basis on relationship between surfactant molecularstructure and function which plays a pivotal role in this area. In this paper, the firstintermediates glycidyl ether was synthesized by epichlorohydrin reacted with dodecanol,tetradecyl alcohol, cetanol, nonyl phenol and cardanol, then reacted with dimethylamine and2-hydyoxy-3-chloro propanesulfate. Five alkyl （and aromatic） glycine betaine zwitterionicssurfactant with definite structures were synthesized.The symbols are C12SZ, C14SZ, C16SZ,NSZ, CSZ. The orthogonal experiments were used to obtain the optimum operatingconditions. The chemical structures of all products were characterized by FT-IR.The surface property and foam property of alkyl betaine zwitterionics surfactants werestudied. The results indicated that as the lengthen carbochain cmc and A_mboth decreased,while γ_cmc, Γ_max, pC₂₀increased. It was shown that C14SZ has excellent foam property.Some properties of aromatic glycine betaine zwitterionics surfactants were investigated,which include surface property, emulsifiability, interface property. The surface activities of thearomatic glycine betaine zwitterionics surfactants show excellent surface property, whichhave the relatively low values of surface tension （30mN/m）. Meanwhile the emulsifiability ofwax was best when the concentration of surfactant in the water was2.0g/L or.1.5g/L. Whenthe concentration of CSZ was0.5g/L, interface tension of CSZ solution and petroleum wasleast (10^-1mN/m-10^-2mN/m), which indicated that this condition could not fit for form lowinterface tension. The effects of NaCl and Na₂CO₃on interface tension were investigated,interface tension could decrease to10^-2mN/m when it exits with both of them.