What is so special about drying

The concentration of impurities which inactivate a catalyst, C, usually becomes obvious from a plot of the rate constant of the catalysed reaction against [C], such as is shown in Fig. 4.7. As the purification of the solvent, the monomer, and the hardware progresses, not only does the intercept diminish, but the slope of the line (usually) increases. It has been shown that if the dependence of on monomer concentration, [M], at [C] = constant and on [C] at [M] = constant is available, the [Imp] originating from the solvent and the [Imp] originating from the monomer can be measured separately (Holdcroft and Plesch, 1984). 

Drying, the removal of water, is a special problem because water is a unique compound and there is a lot of it around. The features which together make water unique include a high dipole moment and polarisability, its amphoteric character, its ability to act as donor and acceptor in hydrogen bond formation, and its smallness. 

---