Domestic Carbon Fiber Reinforced Poly(Phthalazinone Ether Sulfone)s Composites And Their Compatibilizer

Continuous carbon fiber reinforced thermoplastic composites(CCFRTP) have vast application prospects in the field of aerospace and vehicles because of their inherent properties such as high strength and stiffness, higher impact resistance, recyclability, short molding cycle, etc. The industrializations of domestic carbon fibers have made breakthroughs in recent years. However, their applications in the field of CCFRTP are relatively backward as a result of foreign technology blockade and embargo of products, particularly in the field of high performance thermoplastic composites. Poly(phthalazinone ether sulfone)s (PPBES) is a high performance resin, developed by our group, possessing excellent mechanical properties, heat resistance and good solubility in some organic solvents. Thus the solution processing can be adopted to prepare fiber reinforced composites using PPBES as martrix.Herein PPBES was chosen as the matrix, and the domestic continuous carbon fiber (T300,12K) as the reinforced material. The method of solution impregnation and compression molding were adopted to prepare the unidirectional composites. Testing mechanical properties under different temperatures and C scan by ultrasound were conducted to analyze and improve the fabricating process. The best fiber volume content is 57%after the improvement of process. The flexural strength, fiexural modulus and ILSS of the composites are 1620 MPa,137 GPa and 73 MPa, respectively; CF/PPBES composites exhibit excellent mechanical properties at elevated temperature.A kind of poly(phthalazinone ether ketone)s with pendent ester group(PPEK-E) was synthesized as the compatilizer of CF/PPBES composites to improve the melt flow properties of PPBES and interfacial properties of the composites. Copoly(phthalazinone ether ketone)s containing pendent carboxyl group(PPEK-P) was firstly prepared from phenolphthalein (PPL) and 4-(3-chloro-4-hydroxylphenyl)(2H)-phthalazin-l-one (DHPZ) with bis(4-fluorophenyl) ketone (DFK). Then the copoly(phthalazinone ether ketone)s contain pendent ester group (PPEK-E) was synthesized through the direct esterifying reaction of PPEK-E. FT-IR, 'H-NMR, TGA and DSC instruments were conducted to confirm the structures of the resulting polymers. The molecular weight of PPEK-E is 16800, the glass transition temperature (Tg) is 264? and the temperature of 5% mass loss is 450 ?. The campatilizer also can be soluble in some organic solvents, indicating that match with PPBES in thermostability and solubility. The rheology tests show that the melt viscosity of PPBES can be reduced by 20% with 5% PPEK-E mass fraction. With 10% PPEK-E mass fraction, the flexural strength and the interlaminar shear strength of CF/PPBES composites are 1777 MPa and 77 MPa, respectively, which are 9.6% and 5.5% higher than that of CF/PPBES without campatilizer. Scanning electron microscopy show that the campatilizer can improve the impregnation effects of carbon fibers.