ИСТИНА

Stimuli-responsive polymer microgels have proven to be conventional objects suited to create functional materials – superabsorbents, carriers for drugs and dyes, etc. The advantages of using microgels instead of macrogels are the shorter response times to external stimuli and opportunities for managing the internal structure and mechanical properties of the material. The main objective of the presented work is to synthesize the microgels based on poly(N-isopropylacrylamide) (PNIPAM) and poly(acrylic acid) (PAA) interpenetrating networks (IPN), to investigate their properties and to produce the stimuli-responsive polymer films by assembling of IPN miscrogels. To obtain the microgels with IPN structure, in the first stage, the PNIPA microgels were synthesized by thermo-induced precipitation polymerization, then the second subnetwork was obtained by in situ polymerization of acrylic acid within PNIPA microgel particles. Different types of cross-linking agents and cross-linking mechanisms were used to govern the inner network structure of IPN particles. Polymer films were produced by assembling of IPN microgel particles on substrate and temperature treatment, crosslinking by multivalent ions or recrosslinking of disulfide bridges, which are a part of the structure of one of used crosslinking agents. The termo- and pH-induces swelling behavior of obtained films was investigated. The absorption and thermo-induced release of organic dyes and drugs by presented polymer films were studied to demonstrate the potential possibilities of their biomedical application.