Preparation And Characterization Of Polyurethane Carbon Fiber Composite Materials

As a new type of synthetic polymer material,polyurethane elastomer(PUE)has excellent comprehensive properties such as good mechanical properties,water resistance,weather resistance,high and low temperature resistance,and wear resistance.It is widely used in construction,medical treatment,machinery and other fields,among which polyurethane elastomer has made great progress in the direction of bearings.However,it is still one of the current important research directions to meet the application conditions in bearings,bearing bushes and other fields by modifying polyurethane elastomer composites.In this paper,by designing the molecular structure of polyurethane,the hardness and friction properties of polyurethane elastomer are improved under the premise of maintaining the mechanical properties of the polymer matrix.The specific method is to use different types of oligomer polyols as mixed soft segment monomers,toluene diisocyanate(TDI)and 3,3’-dichloro-4,4’-diaminodiphenylmethane(MOCA)as hard segment The monomer is used as the main raw material to synthesize polyurethane elastomer,and carbon fiber(CF)is used as a reinforcing filler to improve the wear resistance of the composite material,and to prepare a polyurethane elastomer composite material with excellent comprehensive performance.The main research contents and experimental conclusions are as follows:1.Using four different types of oligomer polyols as the soft-segment monomers of polyurethane elastomers,and the hard-segment monomers as TDI and MOCA,polyurethane elastomers were prepared by prepolymer method.The basic properties of polyurethane elastomers synthesized from four different polyols were compared.By optimizing the types of polyols and using them as soft segments,the PUE synthesized had the best mechanical properties and wear resistance,and its tensile strength and elongation at break were respectively are 29.24 MPa and 39.44 MPa,183.18% and 216.48%,the friction coefficients are 0.81 and 0.72,and the wear rates are 23.01% and 15.67%,respectively.2.Polyurethane elastomer was prepared by prepolymer method by mixing two best polyols as soft segment monomer and hard segment monomer as TDI and MOCA.Select the optimum soft segment polyol mixing ratio,NCO% content and other conditions to prepare polyurethane elastomer materials,and discuss the influence of the above conditions on the mechanical properties and wear resistance of polyurethane elastomers.When NCO%=8.5%,POH2: POH1=1:3 The tensile strength is stable at 40 MPa,the elongation at break is 231%,the friction coefficient is 0.3,and the wear rate is 0.17%.3.Carbon fiber(CF)is used as a reinforcing filler to increase the wear resistance of PUE,and a high hardness and wear-resistant CF/PUE composite material is prepared.Adding a certain amount of carbon fiber improves its mechanical properties and wear resistance.When the CF content is 7 wt%,the tensile strength can reach 55 MPa,the elongation at break is 298%,the friction coefficient is 0.12,and the wear rate is 0.57%.