Dimethyl maleate can be synthesized from maleic anhydride and methanol, with sulfuric acid acting as acid catalyst, via a nucleophilic acyl substitution for the monomethyl ester, followed by a Fischer esterification reaction for the dimethyl ester.
Dimethyl maleate is used in many organic syntheses as a dienophile for diene synthesis.
[1] Dimethyl maleate has also found use in applications where improvements in the hardness and toughness of polymer films are desired.
This includes, in particular, the improvement of anti-blocking properties of copolymers of vinyl acetate with DMM.
It is also used as an internal modifier to increase the glass transition temperature of styrene or vinyl chloride polymers.