Synthesis and Properties of Fluorine and Silicon Modified Polyurethane Self-assembly Films

Abstract

Fluorinated polyurethane prepolymer(FPU) was synthesized using 2,4-toluene diisocyanate(TDI),poly(ethylene glycol) adipate(PEA),dimethylol propionic acid(DMPA),fluoride monohydric alcohol(F-OH).FPUSi was then synthesized by the in situ acylation reaction of isocyanatopropyltriethoxysilane(Si-NCO) with FPU forming a polymer bearing triethoxysilyl groups.The structures of polymers and self-assembled fluorocarbon films were characterized by FT-IR.The surface properties of self-assembled films were tested by atomic force microscopy et al.FPU and FPUSi showed thermal stability with 5% mass loss at 178 ℃ by thermal gravimetric analysis in nitrogen.The contact angle of the obtained FPUSi self-assembled film was improved to 81°.The tribological experiment showed that the self-assembled films had a very low friction coefficient(about 0.09) and good anti-wear properties under a load of 400 mN.The improved tribological properties of the modified substrate were attributed to the good adherence of FPUSi self-assembled films on the substrate and synergy of FPUSi matrix.