Macroporous polymer beads

Note 1 Macroporous polymers are often network polymers produced in bead form. However, linear polymers can also be prepared in the form of macroporous polymer beads. Note 2 Macroporous polymers swell only slightly in solvents. 

The porogen is usually an inert solvent, or mixtures of inert solvent and polymers. The meso- and macropores in the polymer network are the voids once occupied by the porogen. Individual recipes for the preparation of macroporous polymer beads may seem complex in terms of the number of components involved and the required control of the experimental conditions. The technology, however, for their preparation has been developed to such a degree that excellent control over their properties (e.g. particle size, shape, porosity and chemistry) is routinely achieved. The vast majority of current macroporous polymers are based on styrene-divinylbenzene copolymers. Other suitable monomers include acrylates, methacrylates, hydroxyalkylacrylates, vinylpyridines and vinyl acetate. A wide range of products are available for HPLC in particle sizes from 5-20 p,m, pore diameters from about 2-400 nm, and surface areas from about 50-500 m /g [141,144,146-148]. 

The syndiesis of macroporous polymer beads by suspension polymerization using scCOa as a pressure-adjustable porogen. 

Figure 2. (a) Macroporous polymer beads synthesized using scCOs as the porogen (entry 4, Table 1) (b) Variation in BET surface area of macroporous beads as a Junction of CO2 pressure. 

Figure 3.9 SEM picture of a macroporous polymer bead the bar represents 1 pm.

Washington, D.C., 2001, p.125-6. 012 SYNTHESIS OF MACROPOROUS POLYMER BEADS BY SUSPENSION POLYMERIZATION USING SUPERCRITICAL CARBON DIOXIDE AS A PRESSURE-ADJUSTABLE POROGEN Wood C D Cooper AI Liverpool,University... 

Macroporous polymer beads, synthesized by suspension polymerization, are a class of polymer beads containing a permanent, well-developed porous structure in a dry state and having a wide range of applications—such as support for catalysts, immobilization of enzymes, HPLC columns, liberation of active substances, or adsorbents. 

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