乙酰化纳米纤维素淀粉复合膜的制备及性能

The preparationand properties of acetylated nanocellulose-starch composite film

以乙酰化纳米纤维素(ACNF)作为淀粉膜(ST)的增强相,提高ST的耐水性能和机械性能,并以Nisin为抗菌剂,赋予ACNF-ST复合膜良好的抗菌性能,从而制备出具有良好应用性能的食品包装膜材料。研究表明,由于疏水性的ACNF能够显著提升ST的水接触角,降低ST的吸水率,而乙酰基取代度适度的ANCF能够提高ST的耐水性能,同时,ACNF还能显著提高ST的拉伸强度。研究中,乙酰基取代度为0.27的ACNF-ST表现出较好耐水性能和机械性能,其水接触角为96.8°,水蒸气透过率为0.79 g·mm/(m2·h·KPa),吸水率为17%,拉伸强度为17 MPa。将抗菌剂Nisin引入到ACNF-ST中制备的复合膜具备一定的抗菌性能,通过抗菌实验可知,抗菌膜对大肠杆菌和金黄色葡萄球菌均表现出良好的抗菌能力,抑菌带直径分别为2.85、2.90 cm。

This study employed acetylated nanocellulose(ACNF)as the reinforcing phase of starch(ST)film to prepare a composite film with remarkable mechanical properties and water resistance.Moreover,Nisin was used as the antibacterial agent to endow ACNF-ST excellent antibacterial properties.Thus,composite films applicable to food packaging was prepared accordingly.The results show that ACNF with moderate acetyl substitution degree can significantly improve the water resistance of ST.This is ascribed to that the hydrophobic ACNF can substantially improve the water contact angle of ST and reduce its water absorption.Furthermore,ACNF can lead to improved tensile strength of ST.Within the scope of this study,ACNF-ST with acetyl substitution degree of 0.27 exhibited superior water resistance and mechanical properties.Specifically,the water contact angle was 96.8°,the water vapor transmittance was 0.79 g·mm/(m2·h·KPa),the water absorption rate was 17%and the tensile strength was up to 17 MPa.The resultant composite film by introducing Nisin into ACNF-ST showed considerable antibacterial properties,which possessed good antibacterial capacity to Escherichia coli and Staphylococcus aureus with the inhibition zone diameter of 2.85 and 2.90 cm,respectively.