The RAFT-mediated, surfactant-free, ab initio, batch emulsion polymerization of n-butyl acrylate (nBA) and its copolymerization with methyl methacrylate (MMA) were studied. The control agent was a surface-active trithiocarbonate macromolecular RAFT agent composed of a hydrophilic poly(ethylene oxide) (PEO) block and a hydrophobic dodecyl chain. The homopolymerizations of nBA were fast with high final conversions, and the polymer chains were well-controlled with narrow molar mass distribution. The length of the PEO chain was shown to affect the particle size and the polymerization kinetics directly. We found the conditions to tune the particle size independently from the poly(n-butyl acrylate) chain length by playing with a mixture of macro-RAFT agents with long and short PEO segment or by adding a PEO-based nonionic surfactant. The copolymerizations of nBA and MMA exhibited features very similar to those of the nBA homopolymerizations provided that the molar percentage of MMA did not exceed approximately 75%. In all cases, stable, submicrometric particles composed of amphiphilic diblock copolymer chains were formed.

We report on the generation of surface attached polymer networks through C,H insertion reactions based on carbene intermediates. To this copolymers based on N,Ndimethyl acrylamide, which contain a-diazo ester groups, are generated and coated onto a solid substrate covered with a self-assembled monolayer of a silane. After deposition, films having thicknesses of approximately 120 nm are irradiated with UV light having a wavelength of 254 nm or 360 nm or heated to temperatures between 80 and 180 8C. During the light or heat-induced activation process, carbenes are formed, which react via CAH insertion with any neighboring polymer chain and/or with the self-assembled monolayer on the substrate, thus forming surface-attached polymer networks. To follow the kinetics of the crosslinking process, the conditions are adjusted, so that they range between 5 and 10 min for the UVcrosslinking and 5 to 15 min for the heat-induced crosslinking. UV-patterning of the surface-attached polymer networks through chrome contact masks allows generation of microstructures in the micrometer range. We investigate the layer formation process and describe the formation of microstructured surfaces based on these surface-attached polymer networks.

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