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Polyurethane foaming machineAfter the foam is created, how do you chemically recycle it?

Polyurethane is obtained by polymerization of compounds containing isocyanate-nco, such as TDI and MDI, and compounds containing active hydrogen, such as ROH and RNH2. The polymer contains carbamate bond and urea bond, etc. The two important reactions of this polymerization are as follows

Ocn-r-nco +HO~~OH ~ oocnh-r-nhcoo ~(carbamate group)2 ~ NCO+H2O~ NHCONH~ (urea group)+CO2

Chemical recovery means that under certain conditions, carbamate and urea groups in soft polyurethane foam are broken down and decomposed into polyols, aromatic amines and carbon dioxide by means of alcoholization, hydrolysis, alkaline hydrolysis and pyrolysis, and then the decomposed substances are separated through distillation and other equipment to achieve the purpose of recovery.