Brønsted Acid Catalyzed Stereoselective Polymerization of Vinyl Ethers.

Isotactic poly(vinyl ether)s (PVEs) have recently been identified as a new class of semicrystalline thermoplastics with a valuable combination of mechanical and interfacial properties. Currently, methods to synthesize isotactic PVEs are limited to strong Lewis acids that require a high catalyst loading and limit the accessible scope of monomer substrates for polymerization. Here, we demonstrate the first Brønsted acid catalyzed stereoselective polymerization of vinyl ethers.

Mapping protein-polymer conformations in bioconjugates with atomic precision.

Rational design of protein-polymer bioconjugates is hindered by limited experimental data and mechanistic understanding on interactions between the two. In this communication, nuclear magnetic resonance (NMR) paramagnetic relaxation enhancement (PRE) reports on distances between paramagnetic spin labels and NMR active nuclei, informing on the conformation of conjugated polymers. H/N-heteronuclear single quantum coherence (HSQC) NMR spectra were collected for ubiquitin (Ub) modified with block copolymers incorporating spin labels at different positions along their backbone.

Investigating the Mechanism of Horseradish Peroxidase as a RAFT-Initiase.

A detailed mechanistic and kinetic study of enzymatically initiated RAFT polymerization is performed by combining enzymatic assays and polymerization kinetics analysis. Horseradish peroxidase (HRP) initiated RAFT polymerization of dimethylacrylamide (DMAm) was studied. This polymerization was controlled by 2-(propionic acid)ylethyl trithiocarbonate (PAETC) in the presence of H₂O₂ as a substrate and acetylacetone (ACAC) as a mediator.