Blowing Agent

Azodicarbonamide, ADCA, ADA, or azo(bis)formamide, is a chemical compound with the molecular formula C2H4O2N4.[1] It is a yellow to orange-red, odorless, crystalline powder. Its widespread use in foamed plastics.

The principal use of Azodicarbonamide is in the production of foamed plastics as a blowing agent. The thermal decomposition of Azodicarbonamide results in the evolution of nitrogen, carbon monoxide, carbon dioxide, and ammonia gases, which are trapped in the polymer as bubbles to form a foamed article.

Azodicarbonamide is used in plastics, synthetic leather, and other industries and can be pure or modified. Modification affects the reaction temperatures. Pure Azodicarbonamide generally reacts around 200 °C. In the plastic, leather, and other industries, modified Azodicarbonamide (average decomposition temperature 170 °C) contains additives that accelerate the reaction or react at lower temperatures.

An example of the use of Azodicarbonamide as a blowing agent is found in the manufacture of vinyl (PVC) and EVA-PE foams, where it forms bubbles upon breaking down into gas at high temperature. Vinyl foam is springy and does not slip on smooth surfaces.