Process for producing a transparent shaped polymeric product

A process for efficiently producing a transparent shaped polymeric product, free from defects such as bubbles and strain, of sufficiently high mechanical strength, surface hardness, weather resistance, and impact resistance to serve as a substitute for inorganic glass, consisting essentially of the steps of:

• mixing
• (A) one or more compounds represented by the formula ##STR4## wherein X is H or CH.sub.3 and l is an integer of from 1 to 4, or a prepolymer thereof, in an amount of from 30 to 80% by weight,
• (B) one or more compounds represented by the formula ##STR5## wherein X is H or CH.sub.3, n is an integer of 2, 3 or 4 and m is an integer of from 3 to 6, or a prepolymer thereof, in an amount of from 70 to 20% by weight based on the total amount of (A) and (B), and
• (C) a radical polymerization catalyst in an amount of from 0.5 to 5 parts by weight per 100 parts of the total amount of (A) and (B);
• pouring the mixture into a cell or mold adapted to cast polymerization;
• irradiating it with light of ionizing radiation at a temperature below room temperature to subject it to cast polymerization;
• and then
• heating it to a temperature ranging from 80.degree. C. to the decomposition temperature of the copolymer to be produced to complete the polymerization.