Polymerization catalyst for polythiourethanes, polymerizable liquid composition and process for the production of organic polythiourethane glass with a high refractive index

摘要

Polymerizable liquid compositions containing three components (A), (B) and (C) are provided, wherein component (A) contains at least one cycloaliphatic diisocyanate monomer wherein the weight percentage of free isocyanate groups in component (A) ranges from about 20% to about 50% by weight with respect to the total weight of component (A); component (B) contains at least one polythiol having a molecular weight ranging from 50 to 1,200 g/moles and a functionality ranging from 2 to 5, the components (A) and (B) being present in a weight ratio varying from 0.5:1 to 2:1; and component (C) being a defined polymerization catalyst. A process for the production of organic glass using the polymerizable liquid composition is further provided.