Influence of poly aryl ether ketone resin matrix properties on interfacial properties and interlayer properties of composites

The interfacial strength between PAEK resin matrix and domestic T300 grade carbon fiber (SCF35) carbon fiber was studied by microsphere debonding method for domestic high performance poly aryl ether ketone (PAEK-L, PAEK-H) resins with different characteristics. The composites were prepared by using domestic carbon fiber reinforced poly aryl ether ketone (SCF35/PAEK) thermoplastic prepreg, and the effects of resin matrix on 90° tensile properties, short beam shear properties, type I fracture toughness and type II fracture toughness of the composites were studied. The results show that the interfacial properties of SCF35/PAEK composites are influenced by the fluidity of the resin matrix, and PAEK-H resin with higher fluidity can form a better interfacial bond with the fibers and higher interfacial strength. In the SCF35/PAEK-H composite, the resin-fiber contact angle is ~34.4°, the interfacial shear strength is ~79 MPa, the 90° tensile strength of the composite is ~76 MPa, the modulus is ~9.7 GPa, and the short-beam shear strength is ~92 MPa. While in the lower-fluidity PAEK-L resin and SCF35 carbon fiber composite, the resin-fiber contact angle of ~35.8°, interfacial shear strength of ~64 MPa, composite 90° tensile strength of ~55 MPa, modulus of ~8.6 GPa, and short-beam shear strength of ~86 MPa. The interlaminar properties of SCF35/PAEK composites are influenced by the plastic deformation ability of the resin matrix. PAEK-L, which has a stronger plastic deformation ability of the matrix, has a higher fracture toughness than PAEK-H. The type I fracture toughness of SCF35/PAEK-L is ~938 J/m² and the type II fracture toughness is ~2232 J/m², and the type I fracture toughness of SCF35/PAEK-H is ~638 J/m² and the type II fracture toughness is ~1702 J/m².