Preparation And Application Of Polyglycolic Acid-based Polyol

With the development of chemical industry,coal and dimethyl oxalate versus glycolic acid processes.polyglycolic acid,a new biodegradable material,has attracted more and more attention.Starting from glycolic acid,hydroxyl terminated oligomeric polyols were obtained by polycondensation,and the polymerization degree of oligomeric polyols was controlled by controlling the material ratio of 1,4-butanediol to glycolic acid.The factors influencing the preparation of polyglycolic acid-based polyester polyols were studied.Discussed the effect of quantity 1,4-butanediol Reaction temperature,catalyst content and time,pressure on acid value and hydroxyl value of polyol-polyester using polyglycolic acid.The optimum reaction conditions are defined as follows.1)The addition amount of 1,4-butanediol is 24% of the amount of monomer2)The polymerization temperature is 130 ℃3)The addition amount of zinc acetate dihydrate is 0.2% of the monomer mass4)The vacuum degree and time conditions were as follows: 2 hours of atmospheric pressure prepolymerization,adding 1,4-butanediol,reacting at 50 k Pa for 1 hour,reacting at 30 k Pa for 4 hours,reacting at 10 k Pa for 2 hours,and reacting at 5 k Pa for 2 hours.The viscosity,water content,hydroxyl value and acid value of the polyol were 1013.0CPS,0.05%,381.32 mg KOH / g and 48.85 mg KOH / g,respectively.After determining the best reaction conditions of polyglycolic polyester polyols prepared by melt polymerization,the prepared polyglycolic polyester polyols react with isocyanates,and polyurethane foam materials are prepared by full water foaming process.The effects of the amount of polyester polyol polyglycolate on the bulk density,compressive strength,thermal conductivity and microstructure of polyurethane foam were investigated.The results show that the amount of alcohol-based polyester polyol is 60% of the total mass of the polyol,and the properties of the polyurethane foam sample can meet the requirements of the national standard JG / T314-2012 for rigid polyurethane insulation.Methyl phosphonic acid two methyl ester was added to the polyurethane foam material formulation prepared by polyglycolic acid polyester polyol,so that polyurethane foam had certain flame retardancy.The effects of methyl phosphonic acid two methyl ester on the mechanical properties,thermal conductivity,flame retardancy and Micromorphology of polyurethane foam were investigated experimentally.The research results provide a valuable way for the development of biodegradable polyurethane foam and the development of new polyglycolic acid products.