Organic polymer monoliths preparation

Svec, E (2004a). Preparation and HPLC applications of rigid macroporous organic polymer monoliths. J. Sep. Sci. 27, 747-766. 

This section provides an overview of properties of polymer monolith columns related to 2D-HPLC. Monolithic organic polymer columns, having longer history than silica monoliths, have been reviewed in detail recently by S vec and by Eeltink including their preparation methods and performance (Eeltink et al., 2004 Svec, 2004a). Polymer monolith columns commercially available include polyfstyrene-co-di vinyl benzene) (PSDVB) columns and poly(alkyl methacrylate) columns. 

In contrast to the above technologies that involve packing beads, the most appealing aspect of the monolithic materials discussed in this section is their ease of preparation in a single step from low molecular weight compounds. In situ created monoliths can be prepared from both silica and organic polymers. 

Monolith Column—Porous silica column prepared in situ to completely fill the column tube with a fully porous silica foam skelton. After the organic polymer support is heated off, the silica surface is silylated in place to product bonded-phase surface. Column is high resolution and can be used at high flow rates with relatively low back-pressure (see Chapter 16). 

Monolithic columns are an interesting recent alternative to conventional packed columns. Such columns are created by in situ polymerization from liquid precursors, usually organic polymer- or silica-based. When prepared, monolithic columns have the form of cylindrical rods. They are much more porous than typical packed particle beds, therefore they present significantly lower resistance to mobile phase flow. Consequently, these can be operated at much higher flow rates than conventional columns. The main application of monolithic columns is in high-throughput analysis. 

Several polymer-based monolithic columns have become available commercially in different formats, e.g., disks, membranes, and LC columns with diameters in the range of 0.1-100 mm ID [52], The preparation and application of organic polymer-based monoliths have been reviewed recently [20]. 

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