[Chemical analysis of methacrylate plastics].

It was the object of this study to find quick but exact methods for determining the components of quickly setting methacrylate materials for dentures, dental fillings (PMMA) and for bone surgery. Furthermore, lower-molecular components still being present in the hardened resin were tested. By measuring refraction index and by infrared spectrum and gas-chromatographical analyses the composition of the liquid is obtained. Dimethyl-p-toluidine, hydrochinon and cross-linking agents were determined spectrophotometrically. Filling agents, pigments, plasticizers and soluble components of the powder were determined gravimetrically. The presence of polystyrol is established by infrared analysis, that of benzoyl peroxide by spectroscopic analysis. As to the hardened material, the molecular weight is determined by viscosity measurements and the molecular weight distribution by gel permeability measurements. Residual monomer is found by gas chromatography.