%A Xujuan HUANG,He LIU,Shibin SHANG,Zhaosheng CAI,Jie SONG,Zhanqian SONG %T Synthesis and characterization of castor oil-based polymeric surfactants %0 Journal Article %D 2016 %J Front. Agr. Sci. Eng. %J Frontiers of Agricultural Science and Engineering %@ 2095-7505 %R 10.15302/J-FASE-2016083 %P 46-54 %V 3 %N 1 %U {https://journal.hep.com.cn/fase/EN/10.15302/J-FASE-2016083 %8 2016-03-01 %X

Dehydrated castor oil was epoxidized using phosphoric acid as a catalyst and acetic acid peroxide as an oxidant to produce epoxidized castor oil (ECO). Ring-opening polymerization with stannic chloride was used to produce polymerized ECO (PECO), and sodium hydroxide used to give hydrolyzed PECO (HPECO). The HPECO was characterized by Fourier transform infrared, 1H and 13C nuclear magnetic resonance spectroscopies, gel permeation chromatography, and differential scanning calorimetry. The weight-average molecular weight of soluble PECO and HPECO were 5026 and 2274 g·mol-1, respectively. PECO and HPECO exhibited glass transition. Through neutralizing the carboxylic acid of HPECO with different counterions, castor oil-based polymeric surfactants (HPECO-M, where M= Na+, K+ or triethanolamine ion) exhibited high efficiency to reduce the surface tension of water. The critical micelle concentration (CMC) values of HPECO-M ranged from 0.042 to 0.098 g·L-1 and the minimum equilibrium surface tensions at CMC (gcmc) of HPECO-M ranged from 25.6 to 30.0 mN·m-1. The water-hexadecane interfacial energy was calculated from measured surface tension using harmonic and geometric mean methods. Measured values of water-hexadecane interfacial tension agreed well with those calculated using the harmonic and geometric mean methods.