Effects of interfacial properties on mechanical properties in glass fiber reinforced polypropyleme injection moldings

In injection moldings, glass fibers are treated with various surface treatments. Coupling agents are used to improve interfacial adhesive strength and binders are used to bound glass filaments. Matrix resin was modified with maleic anhydride to improve interfacial adhesive strength. Recently, it is known that binder phase exits between glass fiber and matrix resin. The binder phase has different properties from matrix resin. Therefore, two interfaces exist among fiber, binder phase and matrix resin. These were named ''interphase''. In this study, various combinations of binder and matrix resin were used in order to change the strength of both interfaces. Mechanical properties of interphase depended on two interfacial strengths. Amount of maleic anhydride modified Polypropylene in binder smd matrix phase largely contributed to interfacial shear strength.