Production of Polymeric Materials with Controlled Pore Structure: the “Reactive Gelation” Process

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.