OSA改性高直链玉米淀粉复合疏水膜的制备及性能研究OA北大核心CSTPCD

In this study,high amylose corn starch(HACS)was esterified with octenyl succinic anhydride(OSA)to ob-tain three types of OSA starchs with different degree of modification(OS-3,OS-6,and OS-9).Three types of OSA-modified high amylose corn starch composite films(OS-3/GEL,OS-6/GEL,and OS-9/GEL)were prepared using the as-prepared OSA starchs as raw materials and gelatin as a compound material.The light permeability,water solubility,moisture absorption,and surface hydrophobicity of the composite films were investigated.The results indicated that the properties of OSA-modified starch composite films were greatly improved compared to the unmodified starch composite film.OS-6/GEL exhibited the best performance with high light transmittivity of 87.72%.However,its water solubili-ty,moisture absorption,and water vapor transmittance decreased by 24.5%,29.6%,and 30.35%,respectively.In addition,its maximum static contact angle and dynamic contact angle reached 124.6 °and more than 100 °,respectively,after contact with water for 3 min.X-ray diffraction results indicated that the crystallinity of the original starch was re-duced by the OSA modification,and the compatibility between the film-forming components was improved.Infrared spectroscopy analysis demonstrated that the introduction of OSA group weakened the interaction between the starch and the hydroxyl groups in gelatin molecules,causing the stronger hydrogen bonding between the two groups.Based on the properties and structure of the composite films,it could be concluded that the OSA modification enhanced the hydropho-bic properties of the high amylose corn starch composite films.Through introducing an appropriate number of OSA groups,the resultant OS-6/GEL presented the best properties and excellent hydrophobic performance.