An apparatus for continuously monitoring a photopolymerization reaction in real time by optical pyrometry includes a housing having a chamber; a sample mount that may be disposed within the chamber; a light source for supplying light to induce a photopolymerization reaction in a monomer sample disposed on the sample mount; and an optical pyrometer that may be attached to the housing for measuring temperature of the monomer sample. The temperature of the sample with respect to time is used to monitor progress of the reaction. Another apparatus for monitoring a photopolymerization reaction combines optical pyrometry and infrared spectroscopy. The apparatus includes a sample mount disposed in a beam of an infrared spectrometer a light source for supplying light to induce a photopolymerization reaction in a monomer sample disposed on the sample mount and an optical pyrometer for measuring temperature of the monomer sample.