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The purpose of this research was to determine the influence of material properties on the impact response of a laminate, whereby specimens were fabricated and cured under a vacuum and high temperature using three types of pre-impregnated (prepreg), carbon fibers, namely unidirectional fiber, plain weave woven fiber, and non-crimp fiber (NCF). Each carbon fiber panel, usually known for its low-impact properties, of 16 plies underwent impact testing using a low-velocity impactor and visual damage inspection by C-scan in order to measure the damage area and depth, before and after impact testing. These panels were treated with UV exposure and moisture conditioning for 20 days each. Water contact angles were taken into consideration to determine the hydrophobicity and hydrophillicity of the respective prepreg materials. Experimental results and damage analysis showed that UV exposure and moisture conditioning showcased the variation in impact response and behavior, such as load-carrying capacity, absorbed energy, and impact energy of the carbon fiber panels. This study illustrates that non-crimp carbon fiber laminates were far more superior relative to load capacity than woven and unidirectional laminates, with the NCF-AS laminate exhibiting the highest load capacity of 17,244 lb/in (pre-UV) with only 0.89% decrease after UV exposure. This same laminate also had a 1.54% decrease in sustaining impact and 31.4% increase in wettability of the panel. Moreover, the study shows how symmetric and asymmetric stacking sequences affect the impact behavior of non-crimp fiber laminates. These results may be useful for expanding the capacity of carbon fiber, lowering costs, and growing new markets, thus turning carbon fiber into a viable commercial product.

Sol-gel driven hydroxyapatite (HA) nanoparticles and graphene nanoflakes were incorporated with polycaprolactone (PCL) at different concentrations, and then electrospun at various spinning conditions, such as distance, electrical potential, viscosity and pump speed. The HA nanoparticles were initially amorphous, so they were annealed at elevated temperature (750 °C) for two hours to make them crystalline. Scanning electron microscopy and X-ray diffraction analysis techniques were conducted on the produced nanocomposite fibers. The studies showed that the HA nanoparticles (20–50 nm) and graphene were well distributed in the PCL fibers (500 nm to 5 μm). We believed that such nanoscale biomaterials can accelerate the bone growth and bone regeneration for many patients who are seeking solutions.