The Study Of Effects Of PSF Graft Copolymer On The Processing And Properties Of PSF/Fiber Composites

Polysulfone（PSF）is a special engineering plastic with excellent heat resistance,dimensional stability and excellent mechanical properties,however,its high melt viscosity and high viscosity flow temperature make it difficult to process and form.The performance of fiber-reinforced polysulfone composites is superior to that of PSF.At the same time,the addition of fibers makes the melt viscosity of the composites increase,and the processing conditions are more severe,which limits the further development and application of the composites.Therefore,it is particularly important to reduce the melt viscosity of polysulfone/fiber composites.A moderately branched polysulfone graft copolymer is added as a modifier to the composite material so that the polysulfone/fiber composite material can reduce the melt Viscosity increases and toughens.In this paper,the acylation method was used to synthesize polysulfone-octanoyl chloride graft copolymer PSF-g-8C（G8）with different grafting rate of 8C with anhydrous AlCl₃ as catalyst and acyl chloride as acylating agent.（G8,G12,G16,G20）and polysulfone-carbonyl chloride graft copolymers PSF-g-C（C4,C6,C8,C10,C18）with different carbon chain lengths of 12%.The structure of the obtained polysulfone graft copolymer was characterized by using infrared spectroscopy（FTIR）and nuclear magnetic resonance（NMR）.GF/PSF and CF/PSF were prepared by melt-blending process.The polysulfone graft copolymer was added to GF/PSF and CF/PSF to prepare different PSF-g-8C contents and different PSF-g-8C compositions.Fractional GF/PSF-g-8C/PSF composites and different PSF-gC content,different PSF-gC carbon chain lengths of different CF/PSF-gC/PSF composites,using thermogravimetric analyzer,melt index determination MFR,capillary rheometer,electron universal testing machine and field emission scanning electron microscope（FESEM）were used to characterize and study the heat resistance,flow properties,mechanical properties and surface morphology of the composites.The results showed that the addition of polysulfone graft copolymer significantly reduced the melt viscosity of PSF/GF and PSF/CF composites,but the inherent properties of the composites did not decrease.The addition of 20 wt.%GF and CF significantly increased the heat-resistant temperature,mechanical strength and modulus of PSF,but also reduced the melt index of PSF by 31 to 36%.After different amounts of polysulfone graft copolymer are added to polysulfone/fiber composites,compared to PSF,the melt index of GF/PSF-g-8C/PSF and CF/PSF-g-C/PSF composites improved separately 55 to 101%and 25 to 120%,and the thermal properties and mechanical properties of the ternary composites are well maintained.