Design and Fabrication of Bistratal Functional Anionic Polyurethane Membrane on the Surface of Cashmere Fiber Based on Foaming Micro-Coating and the Studies of its Structure–Activity Relationships

This research aims to reinforce the hand-feeling and washing fastness of anti-pilling and antistatic cashmere textiles based on a traditional “addition” technique. The technical proposal that effectively controls the distribution of polymer on cashmere textiles, based on foaming micro-coating technology, is studied and compared to prevent the superabundant polymer being fixed in the gaps between yarns/fibers and to ensure the graphene is semi-embedded in the membrane of “Table coating.” A couple of flexible hydrophilic anionic polyurethanes are used in micro-coating processing of cashmere purposefully. The effects of different coating technique on pilling, static, anti-ultraviolet, and washing resistance of coated cashmere textiles are studied. The results show that the semi-embedded graphene in the table coating membrane is meaningful to the static resistance. The pilling resistance of cashmere textile covered by polymer membranes is enhanced from grade 1–2 to grade 4–5 when the weight gain rate of “Bottom coating” polyurethane reaches 1.5% (o.w.f.), and its static voltage half-life decreases from 170 s to less than 2 s. In addition, the ultraviolet protection factor (UPF) value of coated cashmere is doubled, and anti-pilling and anti-static effects can withstand five washings.