Versatile multicompartment nanoparticles constructed with two thermo-responsive, pH-responsive and hydrolytic diblock copolymers

Abstract

Multicompartment block copolymer nanoparticles (MCBNs) constructed with a thermo-responsive and base-sensitive poly(N-acryloylsarcosine methyl ester)-block-polystyrene (PNASME-b-PS) and a pH-responsive poly(4-vinylpyridine)-block-polystyrene (P4VP-b-PS) are synthesized by dispersion RAFT polymerization employing two macro-RAFT agents. These MCBNs contain a hydrophobic polystyrene (PS) core and dispersed microdomains formed either by the pH-responsive poly(4-vinylpyridine) (P4VP) and/or the thermo-responsive and base-sensitive poly(N-acryloylsarcosine methyl ester) (PNASME). By changing the polymerization degree of the PS block, the molar ratio of two diblock copolymers, temperature, pH, and tuning the interaction between the acidic poly(N-acryloylsarcosine) block obtained from hydrolysis of PNASME and the alkaline P4VP block, convenient tuning of the size and morphology of the MCBNs is achieved, and well-defined block copolymer nanoparticles including several MCBNs with different microdomains, core–corona particles and shell-bonded core–shell nanoparticles have been prepared.