Interfacial adhesion of glass fibre reinforced polypropylene–maleic anhydride modified polypropylene copolymer composites

In this work, the interfacial adhesion between the glass fibre and polypropylene–maleic anhydride modified polypropylene copolymer has been studied using a microbond test. The interfacial shear strength of the composite increased from 6.58 to 14.85 MPa, with the increase of the content of maleic anhydride modified polypropylene from 0 to 5% in the matrix composition. Oxygen plasma and γ-aminopropyltrimethoxysilane surface treatments were also introduced to modify the surface chemistry of the glass fibre. Compared with γ-aminopropyltrimethoxysilane surface treatment and the control, the interfacial adhesion of the composites of oxygen plasma was stronger in the same content of maleic anhydride modified polypropylene. This trend matches the law of surface morphology, which was imaged by scanning electron microscope. And there was no transcrystallisation at the interface of fibre and matrix resin, and no crystalline morphology change on the matrix resin by a polarised optical microscope.