Comparison of Low Velocity Impact Behavior of Conventional Glass-Polyester and CNF-Filled Glass Polyester Nanophased Composites

摘要

A high intensity ultrasonic liquid processor was used to infuse carbon nano fibers (CNFs) into polyester matrix that was then mixed with catalyst using a high speed mechanical agitator in this research work. The trapped air and reaction volatiles were removed from the mixture using a high vacuum. Dispersion effect on mechanical properties of CNF/polyester was investigated performing sonication dispersion at 40, 60 and 90 minutes, respectively. Sonication dispersion method used to infuse CNFs in the matrix was compared with mechanical mixing method. Results show the significant improvement in the dispersion of CNFs in sonication over the mechanical mixing method. Compression and flexure tests performed on the unfilled, 0.1 wt. %, 0.2 wt.%, 0.3 wt.% and 0.4 wt.% CNF filled polyester, respectively, show increase in modulus and strength with increasing loading percentage of CNF up to 0.2%. Low velocity impact test using Dynatup was performed at 10, 20, and 30 J energy levels on the woven glass polyester composite and 0.2 wt. % CNF filled woven glass polyester nanophased composite, respectively, processed with vacuum assisted transfer molding (VARTM). The fracture morphology of the tested specimens was examined taking photographs with digital camera. There was slight increase in the peak load for all nanophased composite as compared to the conventional composite at different energy levels. The extent of damage was more pronounced in the conventional composite as compared to the nanophased composite.