The Synthesis Of A New Type Of Gemini Organic Silicon Surfactants

There are few reports about the research of organosilane Gemini surfactant currently, Soin tihis study N1-(3-(dimethoxy (methyl)silyl)propyl)ethane-1,2-diamine, bistrimethylsilylether and benzaldehyde as the raw materials were used to synthesize this type of surfactants.This research consists of three steps: first, N1-(3-(dimethoxy(methyl)silyl) propyl)ethane-1,2-diamine and bistrimethylsilyl ether were used to synthetizeN1-(3-trisiloxanepropyl)ethane-1,2-diamine and characterized; secondly, the diamine productobtained from the first step was reacted with benzaldehyde and N1-benzylidene-N2-(trisiloxanepropyl)ethane-1,2-diamine was obtained. This product was structurallycharacterized and its basic properties were measured; thirdly, the product from the step twowas reacted with glycol diglycidyl ether to form the organosilane Gemini surfactant. Itsstructure was characterized and its basic properties were measured.The reaction conditions of each step were examined In the experiments. The betterconditions for synthesizing N1-(3-trisiloxanepropyl)ethane-1,2-diamine are as follows:1:5ofmolar ratio of N1-(3-(dimethoxy(methyl)silyl) propyl) ethane-1,2-diamine andbistrimethylsilyl ether, bistrimethylsilyl ether used as the reaction solvent, the amount ofKOH used was0.45%of the sum amount of the two reactants, reaction temperature90oC forfour hours with a45%product yield. The better reaction condition for synthesis ofN1-benzylidene-N2-(trisiloxanepropyl)ethane-1,2-diamine are:1:1molar ratio ofN1-(3-trisiloxanepropyl)ethane-1,2-diamine and benzaldehyde was used. The reaction wasconducted at40oC under nitrogen atmosphere, absolute ethanol as the solvent with dropwiseaddition of benzaldehyde. After the addition it was heated to reflux for one hour to get theproduct N1-benzylidene-N2-(trisiloxanepropyl)ethane-1,2-diamine. A2:1molar ratio ofN1-benzylidene-N2-(trisiloxanepropyl)ethane-1,2-diamine and glycol diglycidyl ether wasused, isopropanol as solvent under nitrogen atmosphere, glycol diglycidyl ether wasdropwise added. After the addition temperature was raised to90oC, stirred for four hours toget the final product, the organosilane Gemini surfactant. Bistrimethylsilyl ether was used as the solvent to avoid the toxicity and danger of tetrahydrofuran,reduce the impurity,simplify the process,ruduce the cost. KOH which is cheap and easy producted as the catalyst.