Photocrosslinking of silicones .12. UV-curing of silicone acrylates in thin layers - A real time infrared study

Silicone acrylates are useful as model systems for the investigation of the crosslinking process in bulk. The photocrosslinking of silicone acrylates is studied by both RT-IR spectroscopy and a photocalorimetric set-up using a laminate technique. The influence on the polymerization kinetics of light intensity, exposure time, and type of photoinitiator are described. The parameters of the kinetic equation are determined. It is shown that oxygen acts as an inhibitor. Only oxygen which diffuses through the polypropylene protecting layer into the system determines the termination reaction. The experimental results received with calorimetric and infrared methods show analogous results. However, because the experimental conditions differ in the two experimental set-ups, the results are influenced.