Short communicationHydrophobization of starch nanocrystals through esterification in green media

- Starch nanocrystals (SNC) were modified through esterification by using anhydrides.
- Degree of substitution and replacing groups determined the hydrophobicity of SNC.
- The crystalline structure of SNC was preserved after the modifications.
- The modifications could improve dispersion of SNC in non-polar solvents or polymers.

Starch nanocrystals (SNC) were successfully modified through esterification by using dodecenyl succinic anhydride (DDSA), 2-octen-1-ylsuccinic anhydride (OSA) and acetic anhydride (AA) in green media. The chemical modifications were confirmed using FT-IR. The esterification extent of the modified SNC was evaluated by degree of substitution (DS). The modifications imparted hydrophobic character to SNC so that the modified SNC could be dispersed in non-polar solvents such as chloroform, dichloromethane and toluene. It was found that the dispersibility of the modified SNC in non-polar solvents increased with increasing of DS and hydrophobicity of the group replacing the hydroxyl groups in starch. XRD analysis showed that the crystalline structure of SNC was preserved after the modifications.