细菌纤维素的制备及改性研究

【作者】 潘颖；

【导师】 朱平；

【作者基本信息】 青岛大学 ， 纺织化学与染整工程， 2007， 硕士

【摘要】 研究了静态培养时培养条件和培养基成分对细菌纤维素产量的影响，确定了获得较高纤维素产量时的发酵培养条件和培养基成分。通过两种途径制备了改性细菌纤维素。一是在发酵培养基中添加水溶性多糖后合成细菌纤维素；二是把在最优条件下合成的普通细菌纤维素凝胶膜或干膜浸渍多羟基化合物改性。对普通和改性细菌纤维素样品分别进行了性能测试。红外光谱分析表明制备产物为纤维素，并可明显看出改性基团的存在；扫描电镜可看到细菌纤维素的超微细网状结构以及改性后网孔的变化；称重法测得细菌纤维素含水量为88％，改性后则都在90％以上，最高达99％，自然干燥后纤维素膜再溶胀能力也获得了不同程度的提高；金属离子吸附能力测试表明细菌纤维素尤其是改性后对铜离子具有较高的吸附量。另外通过粘度法测试了细菌纤维素的聚合度，DSC测试分析了它的热稳定性。实验结果表明，细菌纤维素是一种良好的新型生物纳米材料，改性后的纤维素性能更加优异，为制备其它高性能复合材料、拓宽细菌纤维素的应用奠定基础。更多还原

【Abstract】 The influence of cultivated conditions and medium components oncellulose yield was studied in this paper, and the optimized fermentationcondition and medium component were obtained.Modified bacterial cellulose was then produced by two methods. One is toproduce bacterial cellulose by adding water soluble polysaccharide to thefermentation medium, the other is to modify common bacterial celluloseproduced in optimized fermentation condition by dipping them into polyhydriccompounds.Performances of common and modified bacterial cellulose were tested.Infra-red spectrums show that the products are cellulose, and modified groupsare also shown obviously in them. The ultrafine reticular structure and changesof meshes after modification can be seen by SEM. The water content of bacterialcellulose is 88% which is tested by weighing method, and above 90% aftermodification, the highest can be up to 99%; the swelling capacities of cellulosefilms are also improved with different degrees after drying in nature. Theadsorptive capacities to metal ion tests show that bacterial cellulose has highadsorbance to Cu²⁺, especially its modification products. In addition, thepolymerization degree and thermal stability of bacterial cellulose were tested byviscosimetry and DSC respectively.The experimental results show that bacterial cellulose is an excellent newkind of nanometer biomaterial, and the performances of its modificationproducts are better, we expect that these results can lay a foundation for makingother high performance composite material and broadening the application ofbacterial cellulose.更多还原