Synthesis Of Polyether And Polyetherester Polyols Catalyzed By DMC Catalyst And Their Application

Double metal cyanide complex （DMC） catalyst was an efficient catalyst in the ring-opening polymerization of epoxides to synthesize polyether polyols,as well as a class of catalysts of potentially industrial applications. Most of current DMC catalysts were only applied to the ring-opening polymerization of propylene oxide（PO）,and had little efficiency or even no catalytic activity used to catalyze other epoxides. In this paper,we successfully achieved hydroxyl-terminated polyepichlorohydrin polyols and polyetherester polyols by ring-opening polymerization of epichlorohydrin and copolymerization of PO and CO₂ using DMC catalysts respectively,which can open up a new idea for the synthesis of special polyethers and the use of CO₂ in the polyurethane industry. In addition,we also synthesized polyurethane elastomer using polyepichlorohydrin polyols and studied its damping properties. The main contents and conclusions are as follows:1. Hydroxyl-terminated polyepichlorohydrin polyols were synthesized for the first time with tri（hydroxyethyl） isocyanurate and bisphenol A as initiators respectively, using DMC catalyst. The effect of reaction conditions such as pretreatment of monomer, polymerization temperature, catalyst concentration,the molar ratio of monomer to initiator et al on the polymerization were investigated. It was found that induction period and reaction time decreased with the increase of temperature and DMC catalyst concentration,but the product color would become darker. the suitable reaction temperature is 135℃, catalyst concentration is 500ppm when THEIC is used as initial agent; the appropriate temperature is 128℃, catalyst concentration is 450ppm when bisphenol A is used as initial agent.2.Hydroxyl-terminated polyetherester polyols were synthesized by copolymerization of PO and CO₂ using DMC catalyst. The effect of reaction conditions such as initiator types, polymerization temperature,pressure,feeding method,catalyst concentration et al on the polymerization was investigated. It was found that propylene carbonate（PC） was also obtained as by-product and the content of PC varied between 10%¹5%; low molecular weight ordinary polyether polyols and bisphenol A are suitable as starting agents, while the THEIC and its derivatives are not; The preferable polymerization condition is: polymerization temperature is 110℃, pressure is 2.5MPa, catalyst concentration is 500ppm, using semi-continuous feeding style. The molar fraction of CO₂ in the copolymer was relatively low,and the molecular weight distribution was relatively wide, so the catalyst has yet to be further improved.3.Hydroxyl-terminated polyetherester polyols were synthesized by copolymerization of PO,MA and CO₂ catalyzed by DMC catalyst. The results demonstrated that the introduction of MA can improve the catalytic activity of the catalyst and shorten the polymerization time.The Cyclic carbonate can be reduced while adding in appropriate amount of MA. the molecular weight distribution was narrower compared with PO-CO₂ copolymer,but still relatively wide. The content of MA was mostly no more than 15% when synthesizing high molecular weight polyetherester polyols, and can be increased with the molecular weight decreased.4.Hydroxyl-terminated polyetherester polyols were synthesized by copolymerization of PO,PhA and CO₂ catalyzed by DMC catalyst. The results demonstrated that the catalytic activity of the catalyst can significantly improved with the introduction of PhA.The polymerization can smoothly go on while the catalyst concentration is only 340ppm. Both the molar fraction of CO₂ in the copolymer and PC by-product will increase with PhA increased.The molecular weight distribution was narrower compared with PO-CO₂-MA copolymer,but still relatively wide.5. Polyurethanes based on polyepichlorohydrin polyols were synthesized, and its damping properties was studied.The results demonstrated that these materials have good damping properties. The damping properties were improved while increasing polyether’s molecular weight, lowerring -NCO content and hard segment of the elastomer,but its glass transition temperature and used temperature also decreased.The material has better damping properties when using TDI and 1,2– propylene glycol as chain extender.