Synthetic mechanism of octenyl succinic anhydride modified corn starch based on shells separation pretreatment

Herein, the synthetic mechanism of octenyl succinic anhydride (OSA) modified corn starch (OSCS) and granule shells (OSCs) based on shells separation pretreatment (SSP) was investigated. High intensity peaks around 1720 and 1570 cm(-1) were observed for OSCs in Fourier transform infrared (FTIR) spectra after SSP. OSCs showed higher degree of substitution (DS) values (ranging from 0.128 to 0.170) than OSCS (0.121) determined by H-1 NMR. The average molecular weight (M-w) of OSA modified CS decreased, due to the introduction of OS groups. X-ray diffraction (XRD) indicated that esterification mainly took place in the amorphous regions of starch granules. X-ray photoelectron spectroscopy (XPS) revealed that a new peak corresponding to Is orbital electrons of Na was obtained due to the introduction of OSA molecules. Meanwhile, lower surface DS and higher fluorescence intensity were noticed for OSCs. Conclusively, SSP would significantly increase the reaction efficiency of OSA modification process of CS. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

The synthetic mechanism of octenyl succinic anhydride (OSA) modified corn starch (OSCS) and granule shells (OSCs) based on shells separation pretreatment (SSP) was investigated in this study. The SSP process resulted in higher degree of substitution values and lower average molecular weight for OSCs compared to OSCS. Additionally, SSP was found to significantly increase the reaction efficiency of OSA modification process of CS.