Fabrication of speedy and super‐water‐absorbing non‐woven cloth with hierarchical three‐dimensional network structure

Abstract A novel speedy and super‐water‐absorbing non‐woven cloth with hierarchical three‐dimensional network (3D‐SS‐PET) was fabricated through the induction of UV copolymerization on polyethylene terephthalate (PET) fibers followed by a volume phase transition. The macroscopic three‐dimensional network implied that the PET non‐woven substrates are complicated three‐dimensional fibrous materials including oriented fibers in preferential or random directions. The microscopic three‐dimensional network is poly(acrylic acid‐ co ‐acrylamide) (poly(AA‐ co ‐AM)) crosslinked copolymer layers on the fiber surface. The rapid volume phase transition was achieved by immersing the swelled non‐woven poly(AA‐ co ‐AM) modified PET (PET‐ g ‐AA‐ co ‐AM) in ethanol. The above process was an essential step to prepare the copolymer chain; after that the fiber surface was extended to form abundant capillary channels and plenty of space between fibers. The water contact angle decreased remarkably from 130° to 0°, while the absorbing capacity of the saturated water and the average water‐absorbing rate experienced an increasing trend, rising from 300 to 324.6 g g −1 in 24 h and 18.6 and 222 g (g min) −1 in 40 s, respectively. It was concluded that surface hydrophilicity and capillaries of the hydrophilic modified macroscopic fibrous structure enhanced the water‐absorbing rate and the swelling process contributed to the higher water absorption capacity. This speedy and super‐water‐absorbing material exhibits great potentiality in diapers, sanitary napkins, wound dressings, surgical pads, and hygroscopic and sweat‐free underwear in extremely cold areas. © 2018 Society of Chemical Industry