Study on the Preparation and Modification of Hydrazodicarbonamide

This study relates to an improved method for they preparation of hydrazodicarbonamide, an intermediate in the preparation of azodicarbonamide which is useful as a chemical blowing agent. Hydrazodicarbonamide is prepared by reaction of urea and hydrazine in acidic medium. Hydrazine is a relatively expensive chemical and this is reflected in the cost of materials derived from it. Accordingly any means of effecting a substantial increase in the yield of hydazodicarbonamide from hydrazine is commercially very important. By Series of comparative experiments, Factors of influencing the yield of biurea which is prepared from the condensation reaction between hydrazine hydrate and urea are studied.