Synthesis And Performance Of High Polymerized Polyglycerol Fatty Acid Ester

Further processing of glycerol to enhance its additional value has received increased attention in the research of biomass chemical.In this paper,the synthesis and properties of polyglycerol and polyglycerol fatty acid ester were studied.High polymerized polyglycerol was prepared in the lab using industrial grade glycerine as raw material.The effects of reaction temperature,amount of catalyst,stirring rate,material mass and vacuum on the polymerization of glycerol were investigated.The relatively optimal process conditions were determined.High polymerized polyglycerol was also prepared in the loop reactor.The free glycerol content and hydroxyl value were measured to determine the conversion rate of glycerol and the average degree of polymerization during the reaction,respectively.The effects of reaction temperature,amount of catalyst and the reactor pressure on glycerol conversion rate and degree of polymerization were investigated.The optimal process conditions are 240?,2.0%catalyst and the reactor pressure of 0.3 MPa.The conversion rate of glycerol could reach 99%and the polymerization degree of the product obtained was more than 20.Fatty acid monoglyceride was synthesised using natural palm kernel oil and excess glycerin by transesterification,and then continue to react with glycerol to generate polyglycerol fatty acid ester by polymerization reaction.The optimum temperature for the transesterification is 160?.Polyglycerol fatty acid ester?PGFE?was prepared separately in loop reaction reactor and in a lab stirred tank reactor.The performances of the reaction in the two systems are compared in respect of the transesterification time,the total time,monoglycerides content and color of product.The HLB value and biodegradability of polyglycerol fatty acid ester?PGFE?were measured.The surface activity,foam properties,emulsifying capacity and wetting property of PGFE and AEO₉ compound were also studied.The results are as follows:the surface activity and emulsifying capacity of mixed systems were improved compared to the individual PGFE or AEO₉.The wetting property of the mixed systems was much better than that of PGFE,while wores than AEO₉.