Interfacial and tensile properties improvement of composites using a modified matrix with epoxy-terminated hyperbranched polyether sulfone

The carbon fiber/epoxy resin (CF/EP) composites have been prepared using CF and the diglycidyl ether of bisphenol-A (DGEBA) matrix, modified by a new epoxy-terminated hyperbranched polyether sulfone (EHPES). Compared with CF/DGEBA composite, the modified CF/EHPES composites achieve excellent performances. The tensile strength, modulus, and elongation at break are increased by 19.1%, 7.9%, and 66.7%, respectively. The results are mainly caused by the strong interfacial properties, the interfacial shear strength (IFSS) of CF/7% EHPES composite is increased by 20.7%. Many crosslinking points enhance the mechanical interlocking between the DGEBA/EHPES matrix and CF surface. The strengthened chemical bonding promotes the formation of a higher density crosslinking network. This study provides a strategy for the domestication of large diameter wind turbine blades.