Sono-RAFT Polymerization-Induced Self-Assembly in Aqueous Dispersion: Synthesis of LCST-type Thermosensitive Nanogels

Abstract

The first sonochemically induced reversible addition-fragmentation chain transfer by the polymerization-induced self-assembly process (Sono-RAFT-PISA) has been investigated. High-frequency ultrasound (490 kHz, 40 W) was applied for the controlled polymerization of N-isopropylacrylamide (NIPAM) in aqueous dispersion via the Sono-RAFT-PISA technique using poly(poly(ethylene glycol) methyl ether acrylate) (PPEGA) as both macromolecular chain transfer agent and surfactant (macro-transurf). The synthesis of PPEGA-b-PNIPAM copolymers in aqueous media at 20 °C (DPn,NIPAM = 204) was found to reach total NIPAM conversion in a short time (60 min.) with narrow molecular weight distribution (D < 1.26). ..