Patent ID: 9181390
Filing Date: 2015-11-10
Classification: C08G

Abstract:
1. A process for preparing a photoactive additive from a dihydroxybenzophenone, a diol chain extender, an end-capping agent, a carbonate precursor, a base, a tertiary amine catalyst, water, and a water-immiscible organic solvent, comprising: combining the dihydroxybenzophenone, diol chain extender, tertiary amine catalyst, water, and water-immiscible solvent to form a reaction mixture; adding the carbonate precursor to the reaction mixture over a first time period while co-adding the base to regulate the reaction pH; adding the end-capping agent to the reaction mixture for a second time period while continuing to add the carbonate precursor and the base; and continuing to add the carbonate precursor and the base to the reaction mixture for a third time period after addition of the end-capping agent is complete to obtain the photoactive additive.