Enhanced the mechanical and dielectric properties of bismaleimide composites modified by graphene oxide grafting with maleic anhydride

摘要

MAH-GO was prepared by grafting maleic anhydride (MAH) on the surface of graphene oxide (GO). The polymer matrix (MBAE) was synthesized by modifying 4,4'-diamino diphenyl methane bismaleimide (BMI) with bisphenol A bisallyl ether (BBE) and diallyl bisphenol A (BBA). The MAH-GO/MBAE composites were obtained by in-situ polymerization, MBAE as matrix and MAH-GO as reinforcement. The microstructure of MAH-GO show that MAH has successfully modified GO, and the grafting ratio was about 11.32% by chemical titration; there are clear folds and lamellar structure on the MAH-GO surface. The micromorphology of MAH-GO/MBAE composites indicate that the fracture cracks are irregular, divergent, and belong to ductile fracture, MAH-GO can uniformly disperse in the matrix resin, when the content of MAH-GO is reasonable. The impact strength and bending strength of the MAH-GO/ MBAE composite are 15.88 kJ/m~2 and 142.13 MPa, which are 67.68% and 43.61% higher than that of MBAE, respectively, the dielectric constant and dielectric loss are about 2.53 and 0.003 from 102 to 103 Hz, when the content of MAH-GO is 0.5 wt%. The mechanical and dielectric properties of the composite have been improved obviously.