Facile, one-step synthesis of self-assembling, cationic block copolymers of poly(2-N-(dimethylaminoethyl) methacrylate) (pDMAEMA) and PEO-PPO-PEO (Pluronic®) is developed. The copolymers are obtained via free-radical polymerization of DMAEMA initiated by Pluronic-radicals generated by cerium (IV). The copolymers possess surface activity, are polycationic at pH<7.1, and self-assemble into micell...

In Research News article 1500394, recently developed methods for activating polymerizations employing RAFT agents are described by T. G. McKenzie, C. Boyer, M. Kamigaito, G. G. Qiao, and co-workers. Direct photolysis, or the use of a multitude of (in)organic photoredox catalysts are shown to be effective for activation of radical polymerizations, while various acids are employed together with d...

Iodonium salts are historical cationic photoinitiators extensively used for the polymerization of epoxides or vinyl ethers. As drawback, absorption iodonium is strongly UV-centered so that this UV photoinitiator can only operate in visible range by mean a photosensitization process. With aim at simplifying composition photopolymerizable resins, numerous chromophores have been covalently linked ...

Models of the index response of diffusion photopolymers typically assume that polymerization is proportional to optical intensity. However, common radical initiators self-terminate. This reduces the polymerization rate and has been shown in steady state to result in polymerization that is proportional to the square root of intensity. We examine the impact of sublinear polymerization rate on the...

The RNA world hypothesis states that the early evolution of life went through a stage in which RNA served both as genome and as catalyst. The central catalyst in an RNA world organism would have been a ribozyme that catalyzed RNA polymerization to facilitate self-replication. An RNA polymerase ribozyme was developed previously in the lab but it is not efficient enough for self-replication. The ...

This article introduces tri-cationic hemicyanine dye employed as a visible-light photoinitiator of acrylic monomers polymerization. This dye, in combination with borate anions, was found to be a very effective photoinitiating system. The kinetics of trimethylolpropane triacrylate polymerization was studied by a microcalorimetric method. The photoredox pair concentration, the co-initiator struct...