Resin and interlayer properties play significant roles in the resistance to impact of fibre-reinforced polymer composites (FRPCs). To investigate the contribution of each factor within the coupled variables to the impact resistance ability of FRPCs, in this work, waterborne polyurethane (WPU) with different tensile elastic modulus, tear strength and bonding strength was obtained. To systematically evaluate the impact resistance and failure mechanisms of the composite materials under varying external loads, impact resistance tests, numerical simulations, and relative weight analysis were conducted. The relative weight analysis results quantified the individual contributions of these three factors to the overall energy absorption capacity across diverse loading conditions. The results indicated that with the increasing rate of the external loading, the resin modulus consistently contributed more significantly to energy absorption than tear strength of resin and interlayer strength, reaching up to 44.3%. In ballistic penetration tests, with the increase in resin modulus, the ballistic performance of PE/WPU laminates demonstrated an S-shaped downward trend. Composites prepared with more rigid matrix could lead to unsatisfactory interlayer damage. A more robust structure could result in fibre pull-out and breakage to a greater extent at the point of forced impact while less in the secondary affected area, presenting comparatively lower impact resistant performance.
Zhou et al. (Mon,) studied this question.