Synthesis of non-ionic polyether modified trisiloxanes surfactant (NTS) from MDHM and polyoxyethylene alkyl allyl ethers (PE-38) with average EO (ethylene oxide) chain length of 7—8 and average molecular weight of 380

was catalyzed by Karstedt catalyst under N2 with no solvent. Its structure was verified by Fourier transform infrared spectroscopy and proton nuclear magnetic resonance. Synthesis of NTS was optimized by using the response surface methodology (RSM). The optimal conditions at which average surface tension (18.417 mN·m-1) repeated three times was obtained

being in agreement with the predicted value (18.177 mN·m-1)

were as follows: reaction mass ratio of n(C=C):n(Si—H)=0.93

amount of catalyst 6.4 mg·kg-1

and reaction temperature and time 94℃ and 2 h

respectively. Hydrolysis of the aqueous solution of NTS at pH 4

7 and 10 also was studied

and the product under acidic and alkaline conditions was stable for about 30 d

while under neutral condition was stable for about 60 d.