Cationically curable polyurethane compositions having vinyl ether functionality

摘要

A cationically curable polyurethane composition comprises the reaction product of an organic polyisocyanate with a transvinylation polyhydric alcohol mixture containing hydroxy groups. The polyisocyanate consumes substantially all of the available hydroxy groups in the transvinylation polyhydric alcohol mixture. These compositions are particularly useful in stereolithography. A method of transvinylation utilizing ultrasonic energy is also disclosed.