The Study Of Preparation And Properties Of Functional Polyurethane Hydrogels

Hydrogels have a wide range of applications in biomedical and intelligent materials due to its excellent comprehensive properties.However,relatively weaker mechanical properties limit its use in a wider range of fields,and stimuli-responsive hydrogels are candidates for the preparation of smart materials.This article takes the functional hydrogel as the starting point and carries out the following three aspects.The effect of polyhydroxy POSS on mechanical properties,water absorption and other properties of hydrogel has been studied.The prepolymers were synthesized with PEG and HDI.And,the polyhydroxy cage silsesquioxane(POSS-OH16)was prepared by a single chemical reaction(Click chemistry)between OVPOSS and Monothioglycerol.Then,POSS-OH16,T7 and β-cyclodextrin(β-CD)were used as cross-linking agents of hydrogel,respectively,and the different ratios of the two cross-linking agents were adjusted to study the morphology,swelling ratio and mechanical properties of the hydrogel.The results showed that when the proper amount of POSS-OH16 was introduced into the hydrogel system,not only the mechanical properties of the hydrogel could be improved,but also the water absorption performance of the hydrogel could be effectively improved.The effect of graphene oxide(GO)on mechanical,water absorption and other properties of hydrogels has been studied.The prepolymers were synthesized with PEG and MDI.The graphene oxide was prepared by Hummers method,then the graphene-containing hydrogel was prepared by using graphene oxide and P-CD as cross-linking agent,and the content of graphene oxide was adjusted to study the change of properties of hydrogel.When the proper amount of graphene oxide was added,the water absorption,mechanical properties and thermal properties of the hydrogel were improved.Light-controlled stimulus-response behavior of azobenzene hydrogels was investigated.P-hydroxy azobenzene monomer was synthesized by diazo-even method.The prepolymers were synthesized with PEG,HDI and AZO,which could make the prepolymer contain light responsive substances.Secondly,β-cyclodextrin(CD)was used as a chemical cross-linking agent to form a three-dimensional network hydrogel.Finally,Effect of different amounts of POSS-OH16 or AZO in the hydrogel system on properties of hydrogel was studied.Finally,the prepared hydrogel has a high water content(greater than 90%),a good mechanical property.Besides,under repeated irradiation of ultraviolet light and visible light,the hydrogel could exhibit light responseperformance.