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Micelle dispersions purification is made available via inline flow dialysis in which micelles are separated from the organic solvent used to dissolve the block copolymers in the micelle formation step. Purification was performed using simple and cost-effective dialysis units employing cellulose membranes. The proposed setup allows us to remove THF from a micelle dispersion within a few hours almost entirely in a looped flow system, without significantly changing the micelle size. Purification is found to be independent of the exact flow rates and only on the circulation time through the dialysis units. The system is not only able to reduce the concentration of the organic solvent, but also water-soluble monomers can be removed. Further, the integration of the method into a full synthesis line to produce encapsulated micelles directly from block copolymer solutions is demonstrated with a throughput of 1.2 g of micelles per hour.

To be applicable to in vivo measuring, molecularly imprinted polymer (MIP) based sensors need to have high reproducibility, require miniaturization, and must be free of toxic materials (such as hea...

We present the synthesis of polymeric nano-particles of targeted morphology in a continuous process via visible light-mediated aqueous RAFT polymerization-induced self-assembly (PISA). A trithiocarbonate-derived poly-(ethylene glycol) (PEG) macroRAFT was activated in the presence of hydroxypropyl methacrylate (HPMA) at 37 degrees C under blue light irradiation (460 nm), leading to the formation of PEG-b-P(HPMA) nanoparticles. The method is attractive in its simplicity-spheres, worms, and vesicles can easily be obtained in a continuous fashion with higher control in comparison to conventional batch procedures. This allows for more accurate production of particle morphologies and scalable synthesis of these nano-objects. The versatility of this process was demonstrated by the in situ encapsulation of an active compound. MCSC-IF-GF [12U1717N]

The polymer product spectra of poly(butyl acrylate), polyBA, samples obtained by full conversion bulk polymerization in the temperature range of 60−140 °C in presence of the chain transfer agent (CTA) octylthiol is analyzed via electrospray ionization−mass spectrometry (ESI−MS) and quantitative 13C NMR. The combination of both these analytical techniques allows for very detailed information on the reaction products associated with the formation of midchain radicals to be obtained. At 60 °C, highly uniform polyBA is generated that consists of the structure alkyl−S−(BA)n−H. With increasing temperature, several other peaks emerge that can be assigned to either conventional termination product or to the three different β-scission products of the so-called midchain radicals that are known to be formed in acrylate polymerization via transfer to polymer reactions. Because of the formation of β-scission products that were formed by scission to either side of the radical functionality, intermolecular transfer to p...

The chain-length dependence of the termination rate coefficient, kt, in butyl acrylate free-radical polymerization has been determined by two independent methods, RAFT-SP-PLP and RAFT-CLD-T, both employing control of radical chain length by reversible addition fragmentation chain transfer (RAFT) polymerization. Within RAFT-SP-PLP, the polymerization induced by a laser single pulse is monitored via near-IR spectroscopy with a time resolution of microseconds. In RAFT-CLD-T, isothermal reaction rate measurements are carried out via DSC under stationary polymerization conditions. The resulting kt data refer to the situation of living/controlled radical polymerization, where both radical chain length and monomer conversion increase during the course of the reaction. The RAFT-SP-PLP measurements were carried out at 60 °C and two pressures, 5 and 1000 bar. The RAFT-CLD-T experiments were run at ambient pressure and at two temperatures, 60 and 80 °C, respectively. In absolute value, the termination rate coefficie...