Synthesis and Characterization of Polysiloxane Grafted Polyamide-Amine Surfactants.

Dendritic-linear surfactants 1G PAMAM-Si and 2G PAMAM-Si were prepared by grafting the single epoxy terminated polydimethylsiloxane (SEPDMS) onto the 1G and 2G dendritic polyamide-amine (PAMAM), respectively. SEPDMS was synthesized by hydrogen-terminated polydimethylsiloxane and allyl glycidyl ether in chloroplatinic acid. The optimum grafting conditions were obtained by single-factor experiments when the mole ratio of SEPDMS and PAMAM was 0.95:1, the reaction temperature was 60 °C, the reaction time was 5 h and the solvent percentage was 60%. The molecular structure of PAMAM-Si was characterized by Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, gel permeation chromatograph and potentiometric acid-base titration. Furthermore, the stability, surface activity and emulsifying ability of the prepared surfactants were studied. The results showed that PAMAM-Si has high stability against dilution, acids, alkalies and salts. PAMAM-Si surfactants can significantly reduce the surface tension of water. And 2G PAMAM-Si is superior to 1G PAMAM-Si at the ability of emulsifying oil. [ABSTRACT FROM AUTHOR]