Alkoxyamine-functionalized latex nanoparticles through RAFT polymerization-induced self-assembly in water

Abstract

The use of a new symmetrical trithiocarbonate holding two alkoxyamine moieties (I), was explored in surfactant-free emulsion polymerization of styrene or n-butyl acrylate through reversible addition-fragmentation chain transfer (RAFT). I revealed as an effective chain transfer agent in the synthesis of well-defined end-functionalized poly(acrylic acid)s (PAA). These macro RAFT agents were further used in water for the preparation of amphiphilic triblock copolymers by polymerization induced self-assembly (PISA). The corresponding final latex particles decorated with alkoxyamine moieties were used to trigger out NMP polymerization of sodium 4-styrene sulfonate (SSNa) in water. The thermal activation of the surface alkoxyamines groups which had hitherto been dormant induced the formation of a double hydrophilic corona PAA-b-PSSNa and a sharp reorganization of latex particles.

A Critical Appraisal of RAFT-Mediated Polymerization-Induced Self-Assembly

“…This approach enables the design of a wide range of spheres, worms, or vesicles exhibiting nonionic, 34,89,111 zwitterionic, 81,103,112 anionic, 102 or cationic 56,71,113 character in the case of RAFT aqueous dispersion polymerization. Similarly, RAFT aqueous emulsion polymerization has been used to produce non-ionic, 35,114 anionic, 105,115−117 or cationic spheres. 118 As expected, the chemical nature of the stabilizer block directly influences the colloidal stability of the nanoparticles.…”

Polymer Synthesis with More Than One Form of Living Polymerization Method

“…Guerrero‐Santos et al . prepared bis‐initiators containing an alkoxyamine and a dithiobenzoate to combine NMP and RAFT polymerization ( Table 7 ).…”

Polymer Nanospheres with Hydrophobic Surface Groups as Supramolecular Building Blocks Produced by Aqueous PISA

“…The final latex particles are composed of amphiphilic block copolymers with predefined and narrowly distributed molar masses. When reversible addition–fragmentation chain transfer (RAFT) polymerization is used as the RDRP technique, surface functionalization can be introduced via the design of the initial RAFT agent (thiocarbonylthio compound Z–C(=S)–SR) . Any chemical function connected to the R‐group will be retained at the hydrophilic chain end and form the particle surface.…”

“…When reversible addition-fragmentation chain transfer (RAFT) polymerization is used as the RDRP technique, surface functionalization can be introduced via the design of the initial RAFT agent (thiocarbonylthio compound Z-C(=S)-SR). [17,18] Any chemical function connected to the R-group will be retained at the hydrophilic chain end and form the particle surface. In principle, this presents an opportunity for making hydrophobic units such as dialkoxynaphthalene available in water, but also entails the challenge of retaining them at the water interface without disrupting the self-assembly process.…”