Summary: A new approach for the production of macroporous polymer materials is presented. Cross‐linked polystyrene particles are first produced by emulsion polymerization. This latex is then swollen by a further addition of monomer and it is successively destabilized, by addition of salt, in such a way that a controlled aggregation is achieved. The system is left aggregating until a gel is obtained. Although polymer gels have their own consistency, latex particles are kept together by weak interactions only, e.g. Van der Waals' forces. In order to impart enough mechanical resistance to the material, the residual monomer is polymerized, thus bridging the polymer particles with cross‐linked polymer. Accordingly, the process has been named “reactive gelation”. In this work, it is shown how it is possible to obtain an accurate control upon the pore structure of the material by properly tuning each step of the process. An application of the obtained material as stationary phase in a separation carried out by high performance liquid chromatography is presented.SEM picture of the macroporous material obtained by reactive gelation.magnified imageSEM picture of the macroporous material obtained by reactive gelation.

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Dedicated to Professor Giambattista Consiglio on the occasion of his 65th birthday A novel process to produce homo-and copolymers by RAFT polymerization in emulsion is presented. It is known that RAFT-controlled radical polymerization can be conducted in emulsion polymerization without disturbing the radical segregation characteristic of this process, thus leading to polymerization rates identical to those encountered in the corresponding nonliving systems. However, RAFT agents are often characterized by very low water solubility and, therefore, they diffuse very slowly from the monomer droplets, where they are initially solubilized, to the reaction loci, i.e., the polymer particles. Accordingly, when used in emulsion polymerization, they are practically excluded from the reaction. In this work, we show that cyclodextrins, well-known for their ability to form water-soluble complexes with hydrophobic molecules, facilitate the transport across the H 2 O phase of the RAFT agent to the polymer particles. Accordingly, chains grow through the entire process in a controlled way. This leads to the production of low-polydispersity polymers with well-defined structure and end functionalities as well as to the possibility of synthesizing block copolymers by a radical mechanism.1. Introduction. -Despite the recent progresses in living radical polymerization (LRP) by RAFT (reversible addition-fragmentation chain transfer), especially in terms of new RAFT agents and produced polymers [1 -3], its application to emulsion polymerization is far from being assessed. On one hand, it has been shown, based on kinetic arguments, that this is the only living mechanism that allows realizing a radical-segregated system where the polymerization rates for the living and the equivalent nonliving processes are identical [4 -6]. On the other hand, the application to conventional emulsion polymerization, i.e., the so-called ab initio polymerization, did not enjoy much success, and good results have been obtained only in mini-emulsion poly-Mini-emulsion polymerization is generally regarded as more complex than conventional emulsion polymerization, which remains the preferred way to carry out industrial polymerizations. However, the application of RAFT to ab initio emulsion polymerization is not straightforward, mainly because of the heterogeneous nature of the process and, specifically, of the partitioning of the RAFT agent among the three phases present in the system: the monomer droplets, the H 2 O phase, and the polymer particles. In this respect, to best achieve satisfactory living conditions in ab initio emulsion polymerization, the RAFT agent must satisfy three main requirements: i) it has to be fully trans-

The scale-up of the HPLC separation of the enantiomers of the flavour norterpenoid ketones˛-ionone and˛-damascone from analytical to preparative scale was achieved using the chromatographic simulated moving bed (SMB) technique. Commercial HPLC columns, with heptakis-(2,3,6-per-O-methyl)-ˇ-cyclodextrin bound to silica gel as chiral stationary phase, were employed for the separation. High-purity enantiomers of both chiral compounds have been obtained with a rather satisfactory productivity.