摘要
纳米细菌纤维素在脱水过程中其微观结构和浸润性、吸水性等会发生很大变化。文中采用自然干燥、微波干燥、冷冻干燥、双滚干燥、离心干燥5种不同的脱水方法对细菌纤维素（BC）进行脱水处理，考察和比较了脱水样品的再吸水性能、微观结构的变化以及脱水过程对样品表面浸润性的影响，并从动力学角度分析了不同样品的吸水过程。结果表明，微观三维网络结构保持较好的样品表现出良好的亲水性。冷冻干燥方式得到的样品浸润性最好，再吸水性能达到其干质量的108倍，其次是离心干燥，其它3种干燥样品的吸水性能均有不同程度的下降（约为10～25倍）。动力学分析表明，细菌纤维素再吸水溶胀过程遵循Fickian扩散定律，BC的网络结构保持越完整，材料的扩散系数越高，对应的再吸水性能也越好。
Microscopic structure and infiltrating water absorbability of nano bacterial cellulose （BC） in the dehydration process will change greatly. BC membranes were dried by five different dehydration methods： natural drying, microwave drying, freeze drying, double roll drying, and centrifugal drying. The water reabsorbability and microstructure changes as well as surface infiltrating of different dehydrated samples were investigated. Dynamics of their water absorbability was also discussed. The results show that specimens which maintain the 3D nano-network well have good hydrophilism. Frozen drying samples have the best water infiltration, of which water absorbability reaches 108 times of the original sample mass, while centrifugal drying samples has a inferior water absorbability. Water absorbability of other samples is subject to different degree of damage （10--25 times）. According to dynamics analysis, it is found that water adsorption and swelling process follow Fickian diffusion law, BC with better 3D network structure has the larger diffusion coefficient, leading to better water absorbability.
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
2013年第10期50-54,共5页
Polymer Materials Science & Engineering
基金
北京市科技计划(z111103066611005)
国家自然科学基金资助项目(51073024,51273021)
关键词
细菌纤维素
干燥
吸水性能
微观结构
吸水动力学
bacterial cellulose
dehydration
water absorbability
microstructure
water-absorbing dynamics
