Ammonium bicarbonate, blowing agents

Chemical blowing agents undergo decomposition at the vulcanisation temperature to form a gaseous species such as nitrogen or carbon dioxide, e.g., azo compounds, nitroso compounds, sulphonyl hydrazide compounds, ammonium carbonate, ammonium bicarbonate and sodium bicarbonate. 

Other inorganic blowing agents used are ammonium carbonate and ammonium bicarbonate which produce mostly carbon dioxide with a small amount of ammonia. 

The manufacture of sponge rubber products such as gaskets for heat exchangers is based on the inclusion in the compound of chemicals which cause gas formation during vulcanization and thereby produce the desired porosity. Sodium bicarbonate and ammonium bicarbonate are examples of popular blowing agents. 

As for decomposable matter, examples are sodium carbonate, ammonium carbonate, sodium nitrite, sodium sulfite, and sodium bicarbonate. Other well-known examples are di-N-nitrosopentamethyl-enetetramine, N,N-disubstituted 5-amino-l,2,3,4-thiatriazole, diesters of azodiformic acid, diazonium salts, sulfonhydrazides, and N-alkyl N-nitrosodiacetoneamine (7). The water produced during the exothermic resol condensation reaction is used as a blowing agent for producing high-density foamed composites. 

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