Some aspects on the synthesis and characterization of dodecenyl succinic anhydride (DDSA)—a curing agent for epoxy resins

Dodecenyl succinic anhydride (DDSA), a liquid anhydride curing agent for epoxy resins, was synthesised from C 12 olefin and maleic anhydride by the “ene synthesis” reaction. C 12 olefin was prepared by the dehydration of lauryl alcohol using Al 2 O 3 (acidic) catalyst. The dehydration was carried out in a flow type reactor. The olefin collected was found to be a mixture of positional isomers of C 12 olefin. Systematic studies were carried out by varying the dehydration temperature, mode of feeding and flow rate of lauryl alcohol, and the C 12 olefin collected were converted into DDSA and mechanical properties of an epoxy resin–DDSA system were evaluated. The C 12 olefins and DDSA were characterized, and the properties correlated with structure and composition. It was found that DDSA derived from C 12 olefin with double bond near to the center of the chain gave better tensile strength than the DDSA derived from C 12 olefin with terminal double bond.