α-纤维素/魔芋葡甘聚糖复合水凝胶的制备及其性能

Preparation and Properties of α-Cellulose/Konjac Glucomannan Composite Hydrogels

摘要:

为提高魔芋葡甘聚糖（Konjac glucomannan,KGM）凝胶的热稳定性和凝胶强度，通过与α-纤维素（α-Cellulose，α-CE）按不同比例复配制得α-CE/KGM复合水凝胶。使用旋转流变仪测定加入不同量α-CE对复合水凝胶流变特性的影响，利用扫描电子显微镜(SEM)、红外光谱(FTIR)和差式扫描量热计(DSC)表征α-CE/KGM水凝胶的表观形貌、微观结构、特征官能团及其热稳定性。结果显示，KGM溶胶和α-CE/KGM溶胶的黏度随剪切速率的增大而减小；在0~300s-1剪切速率内，剪切应力随剪切速率的增大而增大；在0.1~100 Hz频率内，α-CE/KGM的储能模量(G’)低于其损耗模量(G”)，α-CE的添加使复合水凝胶的模量升高。在不同质量比的α-CE/KGM凝胶体系中，当m(α-CE)：m(KGM)=1:1（即α-CE4）时得到的复合水凝胶，熔融吸收峰为122.3℃，热稳定性高有所提高

Abstract:

α-CE/KGM composite hydrogels were prepared by mixing konjac glucomannan (KGM) and α-cellulose (α-CE) in different proportions to improve the thermal stability and gel strength of KGM hydrogels. We used the Rotational Rheometer to research the influence of different quantities of α-CE on the rheological properties of the KGM gels.The surface morphology, characteristic functional groups, thermal stability and microstructure of α-CE/KGM hydrogels were characterized by scanning electron microscope (SEM), infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC). Result reveals that the viscosity of KGM sol and α-CE / KGM sol decreases with the increase of shear rate. In the range of 0 to 300s-1, the shear stress increases with the increase of shear rate. At the selected frequency in the range of 0.1 to 100 Hz, the storage modulus G' of α-CE / KGM is lower than its loss modulus G'', and the addition of α-CE increases the modulus. Especially when m(α-CE):m(KGM)=1:1 (α-CE4), the melting absorption peak is 122.3℃, and the thermal stability is improved.