Title Synthesis of cationic random and diblock brush copolymers and their application for stabilization of titania nanoparticle dispersions /
Translation of Title Katijoninių šepetinių statistinių ir diblokinių kopolimerų sintezė ir jų panaudojimas titano dioksido nanodalelių dispersijoms stabilizuoti.
Authors Klimkevičius, Vaidas
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Pages 29
Keywords [eng] RAFT polymerization ; cationic brush copolymers ; TiO2 nanoparticle dispersions ; stabilization ; rheology
Abstract [eng] There is an increasing demand to develop polymer ceramic nanocomposites with both high transparency and scratch resistance, and optionally with a tailored refractive index. The efficient stabilization of ceramic suspensions and homogeneous incorporation of the ceramic nanoparticles is prerequisite to achieve these properties. Stable dispersions could be achieved using additives (dispersants), thus the development of the materials for stabilization of nanoparticles in dispersions is of growing interest. It is known, that the best dispersants are brush-type polyelectrolytes with complex structure and functionality. The synthesis of molecular brushes with desired architecture and well-defined molecular characteristics and their application for stabilization of nanoparticle dispersions remain very important part of modern polymer chemistry and nanotechnology research. In this work, cationic comb and diblock brush copolymers of low dispersity, desirable molecular weight (degree of polymerization) and composition were synthesized via RAFT polymerization. The optimal conditions for the synthesis of diblock brush copolymers by the RAFT were determined, and diblock brush copolymers with the blocks differing in the length of PEO side chains were synthesized for the first time. Cationic comb and diblock brush copolymers were applied for the stabilization of concentrated aqueous dispersions of titania nanoparticles for the first time. The effect of the copolymer structure (charge density and length of PEO side chains) on stability of the titania nanodispersions was evaluated.
Dissertation Institution Vilniaus universitetas.
Type Summaries of doctoral thesis
Language English
Publication date 2017