细菌纤维素光致变色功能柔性膜的制备及性能

发布时间：2018-02-08 20:25

本文关键词： 细菌纤维素光致变色氧化螺VA嗪氢键复合　出处：《东华大学》2014年硕士论文　论文类型：学位论文

【摘要】：光致变色材料,是一种光学特性在适当的光能辐照后发生改变的新型功能材料,在众多领域具有潜在应用前景。螺VA嗪作为一种新型的光致变色化合物,具有较好的抗疲劳性和光稳定性,此外,它还具有响应快、化学性质稳定等优点,很有希望进入应用领域。然而,光致变色化合物一般都是小分子,要真正的广泛应用比较困难,而高分子材料恰恰在这方面有很大优势。细菌纤维素是一种新型的天然高分子材料,它独特的纳米三维网状结构使其具备优异的物化特性,且表面具有大量的羟基,易于改性和表面修饰。以细菌纤维素为模板和螺VA嗪化合物复合,在传承细菌纤维素优秀性能的同时具有光致变色的特殊性能,使功能化细菌纤维素膜在现代光电子材料领域展现了诱人前景。具体研究内容如下： (1)分别合成含羟基和羧基的两种螺VA嗪化合物。利用红外、质谱和核磁共振氢谱对其结构进行表征,研究了不同外界因素对其光致变色性能产生的影响。螺VA嗪在晶态下没有光致变色现象,在溶液中具有良好的光致变色性能。随着溶剂极性的增强,螺VA嗪溶液呈色体颜色蓝移,最大吸收波长红移。螺VA嗪溶液在不同pH值范围存在颜色的可逆变化。随着温度的降低,螺嗯嗪溶液经紫外光照后颜色变深,恢复速度变慢。 (2)通过TEMPO/NaClO/NaBr氧化体系对细菌纤维素膜进行羧基化改性。研究了乙二胺活化和缓冲溶液体系对提高氧化后羧基含量的影响。在NaClO用量为8mmol/g,反应时间为2小时的最优氧化条件下,羧基含量达1.22mmol/g。氧化过程对细菌纤维素膜的结构和性能影响不大。 (3)通过氢键作用,制备了细菌纤维素,氧化细菌纤维素与螺嗯嗪的复合膜,研究了复合膜的光致变色性能。随着复合量的增加,热性能提高。含羟基螺嗯嗪在氧化细菌纤维素中具有更好的光响应性和光稳定性,经100次显色消色循环后,光密度仅仅下降4.9%,抗疲劳性较好。
[Abstract]:Photochromic material is a kind of new functional material optical properties change in the appropriate light irradiation, has a potential application prospect in many fields. As a new type of screw VA in photochromic compounds with anti fatigue resistance and good light stability, in addition, it also has the advantages of fast response, chemical nature is stable, is expected to enter the field of application. However, photochromic compounds are generally small molecules, to achieve a wide range of applications is difficult, and the polymer material just has a great advantage in this respect.
Bacterial cellulose is a new type of natural polymer materials, its unique nano three-dimensional network structure which has excellent physical and chemical properties, and the surface has a large number of hydroxyl groups, easy modification and surface modification. The bacterial cellulose as templates and triazine compound spiro VA, has the special photochromic properties in the inheritance of bacterial cellulose outstanding performance at the same time, the function of bacterial cellulose membrane shows attractive prospect in the field of modern optoelectronic materials.
The specific research contents are as follows:
(1) two kinds of spiral VA compounds were synthesized containing hydroxyl and carboxyl groups. By using infrared, mass spectrometry and nuclear magnetic resonance spectroscopy to characterize the structure, the influence of external factors on the photochromic properties. Spiro VA piperizine in amorphous state without photochromism, with good color performance the light in the solution. With the increasing of solvent polarity, spiro VA in solution is color color blue shift of the maximum absorption wavelength red shift. In the range of existing spiro VA solution reversible color changes at different pH values. With the decrease of the temperature of spirooxazine solution after irradiation Yan color, restore speed slow down.
(2) through the carboxyl modification of bacterial cellulose membrane for TEMPO/NaClO/NaBr oxidation system. The effects of ethylenediamine activation and buffer solution on the carboxyl content after oxidation. Increase in the amount of NaClO is 8mmol/g, the reaction time is 2 hours under the optimum oxidation conditions, little amount of carboxyl containing 1.22mmol/g. oxidation process on structure and properties of bacteria the influence of cellulose membrane.
(3) through hydrogen bonding, bacterial cellulose prepared composite oxide film of bacterial cellulose and spirooxazine, the composite membrane photochromic properties. With the increase of the amount of the composite, improve the thermal performance. The photoresponsive hydroxyl containing spirooxazine has better oxidation in bacterial cellulose and the stability of light. The 100 color bleaching cycles, optical density dropped only 4.9%, fatigue resistance is good.

【学位授予单位】：东华大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TB383.2

【参考文献】