生物质复合材料制备的溶解技术研究

摘要对细菌纤维素，从溶解速率、溶解度两方面，研究溶解溶剂及相应溶解工艺参数对细菌纤维素溶解的影响，确定了溶解的最佳浓度配比。

本实验采用三种溶解方法：NMMO溶剂，NaOH/尿素，NaOH/尿素/硫脲并控制不同的浓度配比来探究其溶解的速率和溶解度。对溶解后得到的再生膜通过SEM ，XRD和傅氏转换红外线光谱分析仪等来进行显微观察和结构分析。67786

溶解比较可知，当NaOH/尿素/硫脲质量比为4/3/2时，溶解速率最快，且溶解度也较高，但需要进行多次的冷冻解冻过程。而使用NMMO溶剂时，溶解过程较简单。通过SEM观察，细菌纤维素为纳米网状结构，在溶剂中溶解的很彻底。通过XRD和FTIR检测可知，细菌纤维素溶解再生中，其晶型从纤维素Ⅰ型变为了纤维素Ⅱ型。

毕业论文关键词细菌纤维素活化溶解

毕业设计说明书（论文）外文摘要

Abstract The effect of dissolve solvent and the corresponding dissolution process parameters on the dissolution rate and solubility of bacterial cellulose( BC) was investigated and at last the optimum concentration was determined in this paper.

In this work, three dissolution methods including N-methylmorpholine-N-oxide solvent(NMMO), NaOH / urea, NaOH / urea / thiourea were utilized and the effect of different content ratio on the dissolution velocity and dissolution content was studied. The resulting regeneration BC membrane was studied by Field emission scanning electron microscopy(FESEM)，X-ray diffraction(XRD) and Fourier transform infrared spectroscopy (FTIR).

It was founded that the dissolution velocity is the fastest as well as the dissolution content is also high on the condition that the mass ratio of NaOH / urea / thiourea is 4/3/2, but it requires repeatedly frozen. But when N-methylmorpholine-N-oxide was utilized, dissolution process is relatively simple. It can be seen from FESEM images that bacterial cellulose has nano-network structure and was completely dissolved in the solvent. By using XRD and FTIR, it can also be found that after the dissolution followed by regeneration process, the crystal type of BC transforms from celluloseⅠto celluloseⅡ.

Keywords Bacterial cellulose Activation Dissolve

1 绪论 1

1．1细菌纤维素的合成及其特性 1

1．2 细菌纤维素的应用 2

1．3 纤维素溶解的研究进展 4

1.3.1 纤维素的溶解机理 4

1.3.2 纤维素的溶解方法 5

1．4 本论文的主要研究内容 10

2 细菌纤维素溶解实验 10

2．1 实验材料与实验设备 10

2.1.1 实验材料与药品 10

2.1.2 实验设备 11

2．2 实验内容 11

2.2.1 粒状细菌纤维素原材料的预处理 11

2.2.2 膜状细菌纤维素的处理 13

2.2.3 细菌纤维素的活化 13

2.2.4 配制N-甲基吗啉-N-氧化物(NMMO)溶液和碱性溶剂 13

2.2.5 细菌纤维素的溶解 13

2.2.5.1 碱性溶剂溶解细菌纤维素生物质复合材料制备的溶解技术研究:http://www.751com.cn/cailiao/lunwen_76123.html