introduction to 4,4′-diaminodimethane 4,4′-diaminodimethane (mda, methylene dianiline), is an important organic compound with the chemical formula c13h12n2. it has a wide range of applications in industrial production, especially in the synthesis of polyurethane materials. as a high-performance crosslinking agent and curing agent, mda can significantly improve the mechanical strength, heat resistance and chemical stability of...