Amphiphilic molecular brushes with regular polydimethylsiloxane backbone and poly-2-isopropyl-2-oxazoline side chains. 1. Synthesis, characterization and conformation in solution. (5th November 2020)

• Record Type: Journal Article
• Authors: Rodchenko, Serafim; Amirova, Alina; Milenin, Sergey; Ryzhkov, Aleksei; Talalaeva, Evgeniya; Kalinina, Alexandra; Kurlykin, Mikhail; Tenkovtsev, Andrey; Filippov, Alexander
• Is Part Of: European polymer journal. Volume 140(2020)
• Publication Date: 2020-11-05
• Subjects: Hydrosililation -- Functional polydimethylsiloxane -- Molecular brushes -- Poly-2-isopropyl-2-oxazoline -- Molecular hydrodynamic and optics -- Macromolecular conformation; Polymers -- Periodicals; Polymerization -- Periodicals; Polymères -- Périodiques; Polymérisation -- Périodiques; Polymerization; Polymers; Periodicals; Electronic journals; 547.705
• DOI: 10.1016/j.eurpolymj.2020.110035
• Languages: English
• ISSNs: 0014-3057

Abstract

Graphical abstract: Highlights: The synthesis of new regular polydimethylsiloxane with undecene tosylate groups in every fourth siloxane unit was developed. Two molecular brushes with varying side chain length was synthesized based on polydimethylsiloxane macroinitiator. Star-like conformation of both molecular brushes was observed in selective solvents. Molecular brushes exhibit thermoresponsive behavior in water. Abstract: The samples of molecular brushes with a polydimethylsiloxane backbone and side chains of poly-2-isopropyl-2-oxazoline have been synthesized. Regular polydimethylsiloxane with undecene tosylate groups in every fourth siloxane unit was used as a macroinitiator. Two prepared samples are characterized by the same grafting density of side chains, but their different length and copolymer molar mass, 400, 000 and 710000 g⋅mol −1 . Solution behavior study revealed that macroinitiator and its precursor are flexible-chain polymers and macroinitiator's thermodynamic rigidity is similar to one of polydimethylsiloxane. It was shown that the conformation of the graft copolymer molecules in a selective solvent resembles a polymer star because of the backbone of molecular brushes is strongly folded and shielded from the solvent by the side chains. The thermoresponsiveness of the synthesized molecular brushes in aqueous solutions has been demonstrated.