VINYL CHLORIDE AND VINYLIDENE CHLORIDE POLYMERS CAN BE CROSS-LINKED OR OTHERWISE MODIFIED BY REACTION WITH A POLY (DIAZO) COMPOUND SELECTED FROM THE GROUP OF

R-(O-CO-CN2-R'')X AND A-(CN2-R'')X

WHERE X IS AN INTEGER GREATER THAN 1, R IS AN ORGANIC RADICAL INERT TO MODIFICATION REACTIONS, A IS AN AROMATIC RADICAL INERT TO MODIFICATION REACTIONS, AND R'' IS A HYDROGEN, ARYL OR -COOZ RADICAL WHERE Z IS AN ALKYL OR ARYL RADICAL. THE REACTION BETWEEN THE POLY (DIAZO) COMPOUND AND POLYMER CAN BE INITIATED EITHER BY HEATING OR BY EXPOSING TO ULTRAVIOLET RADIATION.