Synthesis Of Polyester Polyol By DMC Catalyst

Polyester polyols are the important raw materials for preparing polyrethane,and their structure,molecular weight,functionality and viscosity have an important impact on the performance of polyurethane products.Polyether polyols and polyester polyols have their own advantages and disadvantages,limiting their respective application areas.If these two types of alcohols are physically mixed to make polyurethane products,the products may have poor performance because of alcohols' different polarity and reactivity with isocyanate.In order to synthesize polyester polyols containing the advantages of polyether polyols,We used double metal cyanide(DMC)complex catalyst to catalyze the reaction of cyclic anhydrides with epoxy(chloro)propane to produce polyols with ester group and ether linkages.And the polyols prepared by the DMC catalyst have the advantages of large molecular weight and narrow molecular weight distribution.So we prepared polyester polyols containing ether linkages by using DMC catalysts.The main research content is as follows:1.The ring-opening polymerization of propylene oxide(PO)and phthalic anhydride(PA)was catalyzed by DMC catalyst with 303 polyether polyol as the initiator.The effects of oil bath temperature,mass fraction of catalyst,molar ratio of PO and PA on polymerization products and reaction process were investigated.The results showed that when the initiator mass is 0.5g,the oil bath temperature is 120°C,the mass fraction of DMC catalyst is 0.06%,and the molar ratio of monomer to PO is 5:1,the reaction conditions are the best.The polyether ester polyhydric polyol prepared had a molecular weight of 1899 and a molecular weight distribution index of 1.292.2.Using bisphenol A(BPA)as the initiator,The ring-opening polymerization of epichlorohydrin(ECH)and phthalic anhydride(PA)was catalyzed by DMC catalyst.The effects of PA content,catalyst mass fraction,oil bath temperature and BPA content on the polymerization product and reaction process were investigated.The results showed that within 1 hour of reaction time,when the oil bath temperature was 130°C,the mass fraction of DMC catalyst was 0.035%,and the mass ratio of ECH,PA and BPA was 10:1.5:0.5,the reaction conditions are the best.The flame retardant polyether ester polyhydric polyol prepared had a molecular weight of 844 and a molecular weight distribution index of 1.251.3.Firstly,the ring-opening polymerization of epichlorohydrin(ECH)and maleic anhydride(MA)was catalyzed by DMC catalyst with bisphenol A(BPA)as the initiator to synthesize the unsaturated linear polyester polyols.Then,the unsaturated hyperbranched polyester polyols were synthesized by using a DMC catalyst to catalyze the ring-opening polymerization of pyromellitic anhydride(PMDA)and epichlorohydrin(ECH)with the unsaturated linear polyester polyols as the initiator.The results showed that 0.3g PMDA was the optimal reaction amount for the reaction under the conditions of 3.0g initiator,130? oil bath temperature,13.0g ECH,and 0.06% DMC catalyst of total mass.The prepared unsaturated hyperbranched polyester polyol had a molecular weight of 11613 and a molecular weight distribution index of 1.242.