KINETICS OF PHOTOPOLYMERIZATION OF DIACRYLATES IN STYRENE DIENE BLOCK-COPOLYMERS

Photopolymerization of dimethacrylic ethers of ethylene-, diethylene-, and tetramethylene glycol in styrene/isoprene thermoelastoplasts, in contrast to solutions, occurs as a process with a linear chain termina tion. Significant decrease in the process rate with an increase in the conversion degree and a decrease in the initial concentration of mono mer is caused by a change in the molecular mobility of media. Using a paramagnetic probe it was demonstrated that the polymerization of dime thacrylic ethers occurs predominantly in polystyrene domains; the dens ity of the networks being formed depends on the length of the glycol c hain. Quantum yields and the lengths of the polymerization chains were determined; rotational and translational mobilities of low-molecular- mass species in modified thermoelastoplasts were evaluated.