Synthesis And Characterization Of Liquid Crystalline Polyurethane And Study On The Properties Ofuhmwpe/Lcpu Compositematerials

In this thesis, the research at home and abroad the development situation of liquid crystalline polymer (LCP) and liquid crystalline polyurethane (LCPU) were reviewed. Structure and properties characterization of LCP and Synthesis, properties application and influences of LCPU were analysised, meanwhile the wide applying prospect, application and the methods of processing and modification of UHMWPE were expatiated. Meanwhile the theory of thermoplastic resin and thermotropic liquid crystalline polymers composite was included.Four kinds of LCPU were synthesized: One part, LCPU1 was synthesized from TDI-100, 4, 4'-biphenol and 1,4-butanediol, in the solution of N,N-Dimethylformamide (DMF). The other part, BHHBP1 and BHHBP(1) were synthesized from 4, 4'-biphenol and 2 - chlorine ethanol, in the solution of ethanol/DMF. LCPU2,LCPU3 and LCPU4 were synthesized from TDI-100, ethylene glycol/1,4-butanediol/1,6-hexandiol and BHHBP1, LCPU(2),LCPU(3) and LCPU(4) were synthesized from ethylene glycol,1,4-butanediol,1,6-hexandiol and BHHBP2, in the solution of DMF. BHHBP was characterized by High Performance Liquid Chromatography(HPLC), Ultra VioletSpectra(UV) and FT-IR. LCPUs were characterized by FT-IR.The thermal properties were viewed by DSC, as well as the structure of mesophasess were observed by POM. LCPUs were blended with UHMWPE in different contents of LCPU through compatilbilizer KH-550. The values of MFR of composite materials were tested, and then the microstructures of composite materials were observed by POM.It showed that the components of BHHBP was different with different solutions. LCPUs which synthesized by BHHBP1 exhibited themotropic liquid crystalline properties at the temperature between Tm and Ti, but LCPUs which synthesized by BHHBP(1) did not exhibited themotropic liquid crystalline properties at the temperature between Tm and Ti. And the Tm and Ti of LCPUs were decreased with the increasing of the number of methylene. In UHMWPE/LCPU composite materials, taking KH-550 as compatibilizer would improve the consistence between UHMWPE and LCPU, which would make LCPU dispersed in UHMWPE uniformly. The rheological property of composite materials would be the best when LCPU/KH-550 is 5. The values of MFR of composite materials had been improved linearly with the increasing of percentage of LCPU, when the ratio of LCPU/KH-550 is fixed.