Dehydrated castor oil was epoxidized using phosphoric acid as a catalyst and acetic acid peroxide as an oxidant to produce epoxidized castor oil(ECO). Ringopening polymerization with stannic chloride was used to produ...Dehydrated castor oil was epoxidized using phosphoric acid as a catalyst and acetic acid peroxide as an oxidant to produce epoxidized castor oil(ECO). Ringopening 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 and13 Cnuclear magnetic resonance spectroscopies,gel permeation chromatography, and differential scanning calorimetry. The weight-average molecular weight of soluble PECO and HPECO were 5026 and2274 g$mol^(–1), respectively. PECO and HPECO exhibited glass transition. Through neutralizing the carboxylic acid of HPECO with different counterions, castor oil-based polymeric surfactants(HPECO-M, where M = Na^+, K^+or triethanolamine ion) exhibited high ef ficiency to reduce the surface tension of water. The critical micelle concentration(CMC) values of HPECO-M ranged from0.042 to 0.098 g$L^(–1)and the minimum equilibrium surface tensions at CMC(g cmc) of HPECO-M ranged from 25.6 to30.0 m N$m^(–1). The water-hexadecane interfacial energy was calculated from measured surface tension using harmonic and geometric mean methods. Measured values of water-hexadecane interfacial tension agreed well with those calculated using the harmonic and geometric mean methods.展开更多
基金support provided by the Natural Science Foundation of Jiangsu Province of China (BK2012063, BK20140973)the National Natural Science Foundation of China (31200446)
文摘Dehydrated castor oil was epoxidized using phosphoric acid as a catalyst and acetic acid peroxide as an oxidant to produce epoxidized castor oil(ECO). Ringopening polymerization with stannic chloride was used to produce polymerized ECO(PECO), and sodium hydroxide used to give hydrolyzed PECO(HPECO). The HPECO was characterized by Fourier transform infrared,1H and13 Cnuclear magnetic resonance spectroscopies,gel permeation chromatography, and differential scanning calorimetry. The weight-average molecular weight of soluble PECO and HPECO were 5026 and2274 g$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 ef ficiency to reduce the surface tension of water. The critical micelle concentration(CMC) values of HPECO-M ranged from0.042 to 0.098 g$L^(–1)and the minimum equilibrium surface tensions at CMC(g cmc) of HPECO-M ranged from 25.6 to30.0 m N$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.
