Investigations have been carried out to study the influence of dendritic polymers on the interfacial adhesion and mechanical properties of GF/PP thermoplastic composites based on continuous filament reinforcement. The dendritic polymer used in this work was an epoxy functional polymer with a molecular weight of approximately 12,000 g/mole. The reinforcing fibers were made from E-glass, the yarns in the fabrics were placed unidirectional and bonded together with thin polyester filaments. The effect of dendritic compatibiliser on the neat PP-resin was studied. The composite properties studied included DMTA, DSC, flexural strength, Charpy impact and SEM analysis. The results have shown that whereas the dendritic additive does not have any negative influence on the neat matrix properties it significantly affects the mechanical properties of the composites. The results of this preliminary study clearly demonstrate the positive effects of dendritic polymer additives as coupling agents in PP-matrices resulting in significantly improved mechanical properties.
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