Fabrication of smart functional microgels and their potential biological and environmental applications

Abstract

The thesis work deals with a detailed investigation on poly (N-isopropylacrylamide-co-methacrylic acid) (PNIPAM)-based functional microgels to understand the unexplored fundamental aspects associated with the colloidal properties of these soft particles and to widen the scope of their applications. A free radical precipitation polymerization method was used for the preparation of microgels. The prepared microgels were characterized through the advent of both classical and modern experimental techniques. A detailed study of the solution properties, including temperature- and pH-induced deswelling, viscosity and colloidal stability of the PNIPAM-based microgels upon incorporation of functional moieties was undertaken. The adsorption behaviour of these microgels at the oil water interface at different temperatures was also investigated as a complimentary study to critically assess the functional systems. The use of different functional microgels in the controlled protein adsorption and delivery, and in environmental decontamination process by catalytic degradation of organic dyes was demonstrated in details. In this work, while, biologically compatible polymer, PNIPAM was employed to prepare the main gel-network, comonomers such as short oligo(ethylene glycol) (OEG) chain derivatives and methacrylic acid and gold nanoparticles were used as functional units. newlineIt is concluded that the ease by which stimuli-responsive microgels could be fabricated and functionalized, opens up new avenues for the sustainable development of materials in a wide range of applications. This application-based tailoring of microgel functionality and structural features turned out to be a particularly appealing attribute for practical uses. newline newline