Influence of surface esterification with alkenyl succinic anhydrides on mechanical properties of corn starch films

The influence of surface esterification modification, by using dodecenyl succinic anhydride (DDSA) and octenyl succinic anhydride (OSA), on mechanical properties of corn starch films was investigated. The results showed that the surface modifications significantly increased tensile strength and Youngʹs modulus of starch films; the modification decreased elongation at break of starch films at 75% RH but enhanced it at 95% RH. The effects of NaOH aqueous solution treating time on mechanical properties of starch films were more notable at 75% RH than at 95% RH. The films modified with DDSA were more strong and rigid, while the films modified with OSA were more flexible and ductile.