Application of temperature and pH responsive microhydrogels for functional finishing of cotton fabric

This paper discusses the developing of an innovative strategy for functional finishing of cotton by application of surface modifying systems based on stimuli responsive microparticulate hydrogels. Dual responsive hydrogels in the microscale were prepared using a temperature responsive synthetic polymer (poly-NiPAAm) and a pH responsive biopolymer (chitosan). The physicochemical characterisation and the stimuli responsiveness of the microparticulate systems have been investigated by microscopy and spectrophotometric techniques, and dynamic light scattering. In an attempt to enhance the incorporation of microparticulate hydrogel to cotton surface, carboxymethylation and aminisation methods for cotton activation have been assessed. Surface modified textile material with incorporated microparticles has been characterised by SEM and XPS techniques in order to determine surface morphology and chemical structure. The capability of the material to respond to different stimuli (pH, temperature, humidity) was studied through swelling/shrinking or hydration/dehydration kinetics and equilibrium using a gravimetric method.