With the development of aerospace industry, the demand for high-temperature carbon fiber composite materials increased day by day, and carbon fiber made before the composite material should be sizing treatment, and sizing agent heat resistance directly affects the composite material Interface performance. AKD Sizing Agent At present, the sizing agent for carbon fiber is mainly epoxy resin, epoxy sizing agent can only be the highest temperature of 180 ℃, and many fields in the aviation field need to work in the high temperature environment of 250 ℃, and there is no resistance to 250 ℃ high temperature carbon fiber sizing So it is of great significance to study the preparation of a high temperature sizing agent for carbon fiber with temperature above 250 ℃. The sizing agent used in this paper is a polyamide imide (PAI) solution, which is obtained by high performance liquid chromatography and infrared spectroscopy. The sizing agent contains only one main component of polyamide imide; (5h) → 210 ℃ (10h). AKD Sizing Agent The results show that the mass fraction of the slurry is higher than 250 ℃. The results show that the mass fraction is 0.1% for the best sizing concentration, the sizing fiber has good surface characteristics, and at 250 ℃ for 24 h weight loss is only 4 ‰. The surface morphology of the carbon fibers before and after sizing was characterized by scanning electron microscopy and atomic force microscopy (AFM). The results show that the sizing can improve the surface morphology of the fibers. AKD Sizing Agent The contact angle of the fibers under different solvents shows that the surface of the fibers XPS test results show that the polarity of the fiber surface after sizing increased, thereby enhancing the resin matrix in the infiltration capacity; the sizing fiber and epoxy resin and bismaleamide resin were formed. The interfacial shear strength decreased by 2.15% and 1.93%, respectively, which indicated that the two kinds of monofilament composites were resistant to high temperature, AKD Sizing Agent and the two kinds of monofilament composite materials were tested for wet heat resistance. The interfacial shear strength decreased by 30.78% and 25.92%, respectively, but the interfacial shear strength was partially restored after removal of water, indicating that the interface was completely cracked at 72 h after boiling.
A sizing agent formed by mixing at least 0.1 to 25 parts by mass of a tertiary amine compound having a molecular weight of 100 g / mol or more and / or a tertiary amine salt (B1) with respect to the component (B) with respect to 100 parts by mass of the component (A) [b] a quaternary ammonium having a cationic site represented by any one of the following general formulas (I) or (II), AKD Sizing Agent which is used as the component (B) with at least 0.1 to 25 parts by mass with respect to 100 parts by mass of the component (A) Salt (B2) and (II), R1 to R5 each represent a hydrocarbon group having 1 to 22 carbon atoms, and a hydrocarbon group having 1 to 22 carbon atoms and an ether structure A hydrocarbon group having 1 to 22 carbon atoms, a hydrocarbon group having 1 to 22 carbon atoms, or a group containing a hydrocarbon group having 1 to 22 carbon atoms and a hydroxyl group, R6 and R7 each represent hydrogen, 8, a group containing a hydrocarbon group having 1 to 8 carbon atoms and an ether structure, AKD Sizing Agent or a group containing a hydrocarbon and an ester structure having 1 to 8 carbon atoms.) [C] A), at least 0.1 to 25 parts by mass of a sizing agent formed as a quaternary phosphonium salt and / or a phosphine compound (B3) of the component (B).