news research progress on alternatives to 4,4′-diaminodiphenylmethane and its potential applications in the field of environmental protection background and importance of 4,4'-diaminodimethane 4,4'-diaminodimethane (mda, methylene dianiline)... 02/18734'-diaminodiphenylmethane and its potential applications in the field of environmental protection Research progress on alternatives to 4