Preparation Of Polytetrahydrofuran Copolymer Elastomer

Polytetrahydrofuran copolyether rubber material was studied and produced in Germany in 1960s.After nearly 60 years of development,it is mainly used in biomedical materials and dental clinic as impression materials.At present,there are few studies,and because of the excellent properties of polytetrahydrofuran,the synthetic rubber has very high strength and excellent low temperature resistance compared with other rubber,so the material has very attractive research prospects.In this thesis,a new preparation method of epoxy compound-tetrahydrofuran copolymer was used.The copolymer is an alternating copolymer of epoxy compound and tetrahydrofuran,and prepared by copolymerization of tetrahydrofuran with allyl glycidyl ether and epichlorohydrin.The double bonds of carbon-carbon are of the molecular chain of the copolymer,which provide sulfur-crosslinking functional groups for the preparation of polytetrahydrofuran elastomers.The polyether elastomer obtained has good oil resistance,heat resistance and cold resistance.This study will further expand the polymerization methods and applications of polytetrahydrofuran and play a role in the development of polytetrahydrofuran materials.In this study,three monomers of tetrahydrofuran?THF?,allyl glycidyl ether?AGE?and epichlorohydrin?ECH?were used as raw materials,and the initiator was the compound of Diphenyl Sulfoxide and boron trifluoride?Ph₂SO·2BF₃?.The ternary copolyether needed in the experiment was prepared.The prepared initiator was characterized by FT-IR.and Vis-UV.The results show that the prepared initiator has complex structure,which is the same as our experimental expectation.The structure and composition of copolyether were characterized by FT-IR and¹H-NMR.The results showed that the functional groups in copolyether are the same as our experimental expectations;GPC analysis showed that only one single peak existed in the copolymers,and no raw material peak and homopolymer peaks were found.The optimum reaction temperature and time were 25?and 8 h,respectively.The optimum ratio of initiator to monomer was 1:100.The optimum monomer ratio was tetrahydrofuran:epichlorohydrin:allyl glycidyl ether=5:4:1.UV-curing and thermal-curing methods were used to prepare polyether elastomers with the ternary copolyether synthesized.By testing the mechanical properties and hardness of elastomers,the effects of different fillers,curing time and temperature on the properties of elastomers were studied,and the optimum curing conditions were determined.The optimum curing conditions for ultraviolet curing are as follows:the content of Polymethyl methacrylate is 50%?mass ratio of ternary copolyether,the same below?,the content of methyl methacrylate is 20%,the content of dioctyl phthalate is 50%,the curing time is 2 h and the polymer ratio is 5:2:3.The optimum curing conditions for thermal curing are as follows:the content of methyl methacrylate is 20%,the content of dioctyl phthalate is 40%,the content of Polymethyl methacrylate is 50%,the curing time is 6 h,the curing temperature is 80?,and the polymer ratio is 5:2:3.