2-Dodecenylsuccinic acid anhydride (DDSA) is used as hardener for epoxy resins like Glycid ether 100 (Epon 812), one of the most widely used embedding media in electron microscopy.Glycid ether cured with DDSA alone will result in rather soft blocks. The combination of DDSA with the hardener methylnadic anhydride (MNA) in varying proportions enables the production of blocks of desired hardness. 2-Dodecenylsuccinic acid anhydride (DDSA) is used as hardener for epoxy resins like Glycid ether 100 (Epon 812), one of the most widely used embedding media in electron microscopy.Glycid ether cured with DDSA alone will result in rather soft blocks. The combination of DDSA with the hardener methylnadic anhydride (MNA) in varying proportions enables the production of blocks of desired hardness.