Papers by Author: Yan Jun Liu

Abstract: Dodecyl polyglucoside was synthesized by glucose and dodecanol using P-toluenesulfonic acid as catalyst. The effects catalyst type, proportion of material, reaction temperature and pressure were discussed in this paper. The most appropriate reaction conditions: mole ratio of laurel alcohol and glucose 6:1, mass of ratio of P-toluenesulfonic and glucose 0.008:1, reaction temperature 120°C and reaction pressure 5.0kPa.

Abstract: In orlder to find out the law between conductivity of polyglycol aliphatic acid ester and concentration and polymerization degree, the relationship between conductivity of polyglycol aliphatic acid ester and concentration and polymerization degree was teated by using DDS-II conductivity experimen instrument, by taking a typical polyethylene glycol 200( 400, 600) dilaurate as the research object. Firstly, the conductivities at the water content from 10% to 90% were tested in the room temperatrure. The results showed that conductivity of the same emulsion increases with increasing the water content, then decreases with increasing the water content. This is because that the emulsion is the O/W emulsion, conductivity increases with increasing the water content. Then the liquid crystal is generated in the emulsion leading to the increase trend of conductivity slowing down. The emulsion changs into the W/O emulsion at last resulting in conductivity decreases with increasing the water content. Secondly, the relationship between conductivity of emulsion and polymerization degree were tested. The results of the experiment show that: the higher the polymerization degree, the smaller the conductivity o f the emulsion is. The reason is the higher the polymerization degree, the less the conductible ions of the emulsion is, finally cause the conductivity changs smaller and smaller.

Abstract: This paper mainly studied the Viscosity of polyethylene glycol dilaurate and the surface tension, discussing the effects of temperature, concentration, rotate speed on the viscosity. The results show that the viscosity of the long carbon chain fatty acid was higher than the short carbochain, and the viscosity decreasing trend with increase of the temperature. The internal structure of emulsion may take place changing due to the temperature changing. The liquid crystal disintegration or occurred phase change could result that the viscosity appeared the abrupt peak. The viscosity of emulsion maybe appear one or two peaks with the changing of concentration, that the viscosity decreasing with increase of the temperature and rotate speed.

Abstract: A novel PEG200 lauric acid diester was synthesized high yield by direct esterification using polyethylene glycol and lauric acid respectively was presented in this work. The product of PEG200 lauric acid diester was characterized by a fourier transform infrared spectrometer(FTIR). The effects of catalyst, reaction time, reaction temperature and molar ratio on the reaction were discussed. The optimum synthetic condition of PEG200 lauric acid diester: esynthesis is based on protection of N₂ and the ressure is 0.08Mpa. Using mass fraction 0.45% in p-toluene sulphonic acid as catalyst, molar ratio of polyethylene glycol and oleic acid 1:1.95, reaction temperature about 130-140°C, and reaction time 9-10h. The results of testing of diester products showed that the yield of PEG200 lauric acid diester is 98.2%.And this article reviewed the effect of concentration on viscosity. The characteristic curve of Viscosity-Concentration showed the viscosity increased with increase of the concentration which brought about the increase of particle size. Especially focusing on the maximum viscosity appeard on 80% because of the phenomenon of reverse micelles. Then the viscosity decreased with increase of the concentration.