A simple procedure for extracting methacrylic acid from water-miscible methacrylates.

A simple procedure for removing methacrylic acid from water-miscible methacrylates is described. One volume of monomer is diluted with 9 volumes of diethyl ether. Three consecutive extractions are carried out with 5% aqueous NaHCO3 at 4 C. Residual water is removed by shaking with anhydrous sodium sulfate. The ether is removed by flash evaporation on a Büchi Rotavapor. Weak alkali extraction produces good quality semithin sections which are free of background staining. This method may be a useful alternative to existing methods for removal of methacrylic acid.