Improved soiling resistance of polypropylene fibers on the addition of synthetic compounds

With the aim of enhancing the soil resistance of polypropylene (PP) fibers, polydimethylsiloxane (PDMS) and/or oleamide (OA) were added, and the soiling and wear resistances of the obtained fibers were evaluated. Films made from PP with the addition of PDMS and/or OA were fabricated and their water repellencies were evaluated by using droplets to measure their contact angles. The water contact angle increased with increasing amount of PDMS and/or OA added to PP. These blended resins were then used to produce fibers, which were in turn used to form fabrics. The soil resistances of these fabrics were evaluated by immersing them in aqueous solutions of a water-soluble artificial soiling substance for 1 min. Fiber G, for which both PDMS and OA had been added to PP, had a soiling ratio that was about 8–15% lower than that of pure PP fibers to which nothing had been added. Longer immersion of 24 h resulted in Fiber E, for which only PDMS had been added, having the lowest soiling ratio. In contrast, Fibers L and G (produced by adding OA) had relatively high soiling ratios when immersed for a long time. The wear resistances of knitted fabrics were evaluated using an abrasion tester. Fabric made from pure PP fibers had holes after 20 cycles of abrasion, whereas fabrics formed from fibers to which PDMS and/or OA had been added did not have holes even after 100 cycles of abrasion, which represents a remarkable improvement in wear resistance.