Novel Synthesis Pathways for PNIPAAm-Based Hydrogels and Their Application in Thermosensitive Textiles

Abstract

The research focus is lately directed towards the development of the thermosensitive textiles with advanced functionalities. As sources of inspiration for a progress in the field of these innovative materials, stimuli-sensitive polymer engineering, plasma surface engineering, and nanotechnology have been extensively explored. In this work, the polymerization methods for synthesis of Poly(N-isopropylacrylamide), PNIPAAm-based hydrogels, incorporating natural biopolymers (chitosan and b-cyclodextrin), for achieving dual temperature/pH sensitivity and improvement of relevant loading capacity towards specific guest molecules are outlined. These PNIPAAm-based hydrogels are of great interest for biomedical applications (transdermal drug delivery, cell encapsulation, wound dressing, tissue repair, etc.) and intelligent stimuli-sensitive textile coatings for moisture regain control, antimicrobial properties, water and/or oil repellency, and fragrance release. The strategies for synthesis of PNIPAAm-based hydrogels (macro and micro forms) and their proper integration onto textiles through the plasma surface modification, graft polymerization, and coatings are discussed. Novel possibilities for creating hydrogels based on atmospheric plasma polymerization of NIPAAm monomers in liquids have alos been reported. Plasma polymerization in liquids demonstrated a great technological potential given that it may be performed without the use of chemical initiators and even without cross-linking agents, offering multiple advantages over the conventional hydrothermal polymerization methods. Further research on adequate chemical and physical structures of PNIPAAm-based hydrogels and methods of their applications in textiles could boost a progress in the domain of smart textiles, implying novel performances and end uses.