Deepening the insight into poly(butylene oxide)-block-poly(glycidol) synthesis and self-assemblies: micelles, worms and vesicles

Abstract

Improved synthesis and well controlled self-assembly of PBO-b-PG amphiphilic diblock copolymers led to homogenous phases of micelles, worms and vesicles.

Fully amorphous atactic and isotactic block copolymers and their self-assembly into nano- and microscopic vesicles

“…3 repetitive measurements were performed at 25°C, using methanol as solvent and reference, and a monomer or polymer concentration of 50 mg mL −1 (5% w/v). The specific rotation is stated and was calculated from the measured optical rotation α as follows: [α] 25 D = α/(l•c) with [α] 25 D specific rotation, l path length and c concentration.…”

“…The atactic and isotactic poly(butylene oxide)-block-poly(glycidol) (PBO-b-PG) BCPs were synthesised in two sequential, microwave-based anionic ring-opening polymerisations following a previously published protocol. 25 The polymer configuration was predetermined using either racemic or enantiopure butylene oxide (BO) and 1-ethoxyethyl glycidyl ether (EEGE) monomers. The detailed synthetic protocols for all polymers can be found in the ESI.…”

“…The microwave-assisted anionic ring-opening polymerisation of atactic and isotactic PBO-b-PG BCPs followed a previously established procedure. 25 This involved three steps, as displayed in Fig. 1a: (1) synthesis of a hydrophobic PBO homopolymer, which served as a precursor for the following chain extension;…”

“…The f-ratios of the BCPs of 34-35% were in the range where vesicular structures were reported for atactic PBO-b-PGs when subjected to aqueous self-assembly. 25 Exemplary SEC traces and their dispersities are shown in the inset in Fig. 2 for the (S)-PBO homopolymer, (S)-PG homopolymer and (S)-BCP.…”

“…In this work, a straightforward approach to obtain small and giant unilamellar vesicles (SUVs, GUVs) composed of fully amorphous isotactic BCPs is presented. Poly (butylene oxide)-block-poly(glycidol) (PBO-b-PG) was chosen as vesicle-forming BCP, since its atactic version fulfills all requirements to prepare biomedically applicable nanoparticles: 24,25 both blocks are biocompatible, fully amorphous [26][27][28] and their side groups allow for the introduction of isotacticity. Here, a set of three amphiphilic PBO-b-PG BCPs with either atactic (R/ S), isotactic (R) or isotactic (S) configuration, was synthesised.…”