Abstract: Me3SiOSiMeROSiMe3(R=CH2(CH2)7CHOCH2)(AETS) has been synthesized through a hydrosilation of 1,2-eposy-9-decene(ED) with 1,1,1,3,5,5,5-heptamethyltrisiloxane(MDHM) in the presence of hexachloroplatinic(Ⅳ) acid as the catalyst. Then a novel cationic trisiloxane surfactant with the formula Me3SiOSiMeR2OSiMe3(R2=CH2(CH2)7CHOHCH2N(CH2CH2OH)2)(CTSS) has been prepared through the ring-opening reaction of diethanolamine(DEA) with AETS. The structure of CTSS was characterized by IR and 1H NMR. The surface intension, wettability and stability in different pH of CTSS were investigated. The effect of reaction conditions on the synthesis of AETS and CTSS were investigated respectively. The optimized reaction conditions for the preparation of AETS are that the molar ratio of ED and MDHM is 1.1∶1, the catalyst loading is 0.075% of the n（MDHM）, the reaction time is 5 hours and the reaction temperature is 80 ℃. While the optimized reaction conditions to obtain CTSS are that the ratio of n(AETS) to n(DEA) is 1∶1.05, the reaction time is 3 h and the reaction temperature is 80 ℃. CTSS can reduced the surface tension of distilled water to 20.0 mN/m at the critical micelle concentration(CMC) of 1.3×10-3 mol/L. In addition, CTSS also has better wettability and maintains stable in pH 6.5~8.0.

Key words: trisiloxane, surfactant, surface intension, wettability, emulsibility