| abstract |
In the suspension polymerization of (meth) acrylic acid esters or of vinyl aromatics or of mixtures of such monomers, an “emulsion polymer” is formed as a by-product, which reduces the yield. The aim is to keep the proportion of the emulsion polymer as low as possible, since this also impairs the physical properties of the suspension polymer.n n n The formation of the emulsion polymer is reduced if the polymerization is carried out with the addition of polyvalent phosphonic acids or their alkali metal or ammonium salts or with the addition of alkali metal or ammonium salts of condensed inorganic phosphates, for example Graham's salt.n n n Production of suspension polymers, in particular based on PMMA, for the production of plastic articles. |