Photostimulation of Astralenes during Polymerization: Influence on the Reaction Kinetics and the Properties of the Resulting Material

The development of communication systems requires the development of innovative materials capable of limiting the laser radiation power in optical components. One promising approach involves composites based on polyacrylates and astralenes. In our previous study, we demonstrated the successful modification of astralenes for incorporation into acrylates. In this work, we investigate the effect of astralenes on photopolymerization. Photostimulation of these nanoparticles causes the conversion of molecular oxygen to its singlet state, which does not inhibit radical polymerization. Experimental results showed that the introduction of astralenes slows photopolymerization, reducing the reaction rate by approximately half. Furthermore, in situ generation of singlet oxygen by irradiating astralenes with red light makes the polymerization rate comparable to that observed for undoped monomers. Neither the addition of astralenes at concentrations from 0.01 to 0.5% nor the singlet oxygen generated by them significantly affects the thermal stability, glass transition temperature, and the proportion of the network structure in the material.