干燥方法对细菌纤维素膜的结构与性能影响

Influnence of Drying Method on Structure and Properties of Bacterial Cellulose Membranes

本文探讨了热风干燥、真空干燥、冷冻干燥、液氮-冷冻干燥四种不同干燥方法对细菌纤维素膜的结构性能的影响。利用FTIR、X衍射、SEM测定不同干燥方式膜的分子结构和结晶度,并对膜的力学性能、复水率和溶胀率以及对活性物质的吸附与解吸附性能进行了分析,结果表明,不同干燥方式均保留了纤维素膜原有的分子结构,但水分流失方式的区别使其分子内立体及空间结构不一致,膜空间网状结构维持度及分子间孔隙依次为:液氮-冷冻干燥冷冻干燥真空干燥热风干燥,溶胀率(81.31%)和复水率(53.07%)表明液氮-冷冻干燥膜效果最优,且液氮-冷冻干燥膜和冷冻干燥膜由于空间结构的关系更易吸附活性维生素D,其吸附平衡和解吸附平衡所需的时间越长。

In this paper,the influence of drying methods(hot air drying,vacuum drying,freeze drying,and liquid nitrogen-freeze drying)on the structural and properties of bacterial cellulose membranes was investigated.FTIR,X-ray diffraction,and SEM were used to determine the molecular structure and crystallinity of membranes by different drying methods.The mechanical properties,rehydration rate,swelling rate of the membranes and the adsorption and desorption performance of active substances were analyzed,and the results showed that the drying methods retain the original molecular structure of the cellulose membrane,but the difference in the way of water loss makes the three-dimensional and spatial structure of the molecule inconsistent.The maintenance degree of the membrane space network structure and the intermolecular pores were:liquid nitrogen-freeze dryingfreeze drying vacuum dryinghot air drying,the swelling rate(81.31%)and rehydration rate(53.07%)showed that the effect of liquid nitrogen-freeze-drying membrane was the best.The relationship between liquid nitrogen-freeze-drying membrane and freeze-drying membrane was due to the spatial structure,and the easier it was to adsorb active vitamin D,the longer the time required for its adsorption equilibrium and desorption equilibrium.