Experimental determination and numerical prediction of mechanical properties of injection molded self-reinforcing polymer composites

A novel method to calculate the distribution of tensile modulus of injection molded PET/LCP blends across the thickness of the mold cavity has been developed, based on the generalized Halpin-Tsai composite model, but with a variable fiber aspect ratio. Using this method, we are able to make a number of predictions regarding the effects of melt temperature, mold temperature, injection speed, and LCP volume fraction on the moduli of the injection molded blends. Our predictions show that in order to optimize the reinforcement effect of the in-situ formed LCP fibers in the blends, low mold temperature and low injection speed are required. These results are in good agreement with experimental results.