The weak interfacial adhesion of glass fiber-reinforced polypropylene (PP+GF) composites limits their use in structural applications. While compatibilizers like maleic anhydride-grafted polymers are commonly used, their working mechanisms require further investigation. This study examines the adhesion enhancement in PP+GF composites by comparing three compatibilizers: PP-g-MAH (MAH, Maleic Anhydride), POE-g-MAH (POE, Polyolefin Elastomer), and EPDM-g-MAH (EPDM, Ethylene-Propylene-Diene Monomer). Results show that PP-g-MAH provides the most significant improvement. Scanning Electron Microscopy revealed that this enhancement is associated with the formation of micro-porous structures in the composite, which increase surface energy and contribute to mechanical interlocking. X-ray Diffraction and Gel Permeation Chromatography analyses indicate that changes in crystallinity and molecular weight were not primary factors in the adhesion improvement. This work provides an alternative perspective for understanding adhesion mechanisms in polypropylene composites.
Lin et al. (Sun,) studied this question.