Temperature‐sensitive poly(N‐tert‐butylacrylamide‐co‐acrylamide) hydrogels bonded on cotton fabrics by coating technique

Different from the conventional method of developing stimuli‐sensitive textiles by graft copolymerization of environmental responsive polymers onto the fabric, the coating technique was applied to bond temperature‐sensitive hydrogels with cotton fabric through chemical covalent in our work. A temperature‐sensitive linear copolymer of N‐tert‐butylacrylamide (NTBA) and acrylamide (AAm) was prepared in methanol. Then, the cotton fabrics were coated using an aqueous solution of this copolymer containing 1,2,3,4‐butanetertracarboxylic acid as a crosslinker and sodium hypophosphite (SHP) as a catalyst, followed by drying and curing. The surface of the cotton fabrics was bonded on more or less coatings of poly (NTBA‐co‐AAm) hydrogels, as verified by Fourier transform infrared spectroscopy and scanning electron microscopy images. The poly(NTBA‐co‐AAm) hydrogels‐coated fabrics exhibited temperature sensitive, and the temperature interval of the deswelling transition was higher than lower critical solution temperature of linear copolymer solution. The coated fabrics presented good water‐impermeable ability because of the swelling of hydrogels bonded, especially when the add‐on was as high as 14.14%. Environmental scanning electron microscopy images revealed that coating hydrogels swelled and covered on the surface as a barrier to prevent water from penetrating once the coated fabric came into contact with water. The findings demonstrate that the temperature‐sensitive hydrogels can be covalently bonded on the cotton fabrics by coating technique and the coated fabrics have potential on immersion fabrics. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009