Research on the surface roughness of aramid fibers via the surface modification

The friction among yarns plays an important role in the energy absorption, and in previous research, it has been found that compared to other types of woven fabrics, the aramid angle-interlock woven fabric has shown the weak capability of the energy absorption due to the low friction among yarns. However, the surface of aramid yarn is very smooth, and it is difficult to increase the friction among aramid yarns directly, because of high crystallinity and low chemical activity of the aramid yarn. Therefore, the fiber surface needs to be modified to provide the surface roughness to increase the friction among yarns. In this paper, acetone, calcium chloride, and hydrogen peroxide were used to modify the aramid fiber surface in order to increase the surface roughness, and the effects of which were demonstrated by the infiltration of the fiber. The results showed that the reagent of acetone and calcium chloride, and the reagent of acetone and hydrogen peroxide, had strong capability to increase the surface roughness of the aramid fibers. It was also found that the strength of the aramid fiber treated by the reagent of acetone and calcium chloride achieved an increase of 10.2%, while that by the reagent of acetone and hydrogen peroxide demonstrated a decrease of 4.6%. Therefore, the reagent of acetone and calcium chloride maybe an ideal choice to provide higher surface roughness, with no negative influence on the breaking strength of the aramid fiber, when the aramid fiber is modified to be considered as the ballistic material.