摘要
壳聚糖基复合材料在水凝胶领域应用广泛,但其制备过程中通常需要有毒性的化学交联剂和经过繁琐的化学修饰等过程。将壳聚糖、丙烯酸和钛酸四丁酯共混,在遇水后,通过钛酸四丁酯的原位水解形成的纳米二氧化钛作为物理交联剂,一步法制备复合水凝胶,过程简单且无需化学交联剂。在此复合水凝胶中,纳米二氧化钛作为交联剂和光催化剂,丙烯酸可以提高壳聚糖的吸水性,同时丙烯酸和壳聚糖表面的羟基和氨基等基团又可以增强二氧化钛的光催化性能。利用X射线衍射、傅里叶红外光谱、扫描电镜和透射电镜等考察其形貌与结构等特征,并通过吸水试验和亚甲基蓝的光降解试验测试了其溶胀及光催化性能。结果表明:该复合水凝胶内部为多孔结构,粒径约为5~12 nm的二氧化钛均匀分散在复合水凝胶中,无团聚现象。该复合水凝胶材料具有优良的吸水性,其饱和吸水率约为1500%,在模拟自然光下对亚甲基蓝有较好的光催化降解效果。以上结果表明该材料在污水处理领域具有一定的应用前景。
Large-scale production of chitosan-based composite hydrogels is limited because the preparation process is extremely complicated,which involved complex process of chemical modification,and the utilization of some noxious chemical crosslinking agents.In order to solve these problems,the authors fabricated in-situ physically cross-linked chitosan/acrylic acid/titanium dioxide composite hydrogel by one-step method.In this hydrogel,the acrylic acid can increase the water absorption capability of the composite hydrogel,and nano-size titanium dioxide was used as the crosslinking agent.This method can be much simpler and did not need any chemical cross-linking.At the same time,the titanium dioxide in this hydrogel can be also used as a photo catalyst,and the hydroxyl groups and amino groups of the acrylic and chitosan can enhance the photo catalytic performance of the titanium dioxide.The SEM images showed that the composite hydrogel had a 3D porous structure with the pore diameter ranging from 200-300 nm,which indicated that the composite hydrogel may have a good water loading performance.The TEM images showed that the titanium dioxide with a particle size of about 5-12 nm were well-dispersed in the composite hydrogel without agglomeration,indicating the good compatibility among the titanium dioxide,chitosan and acrylic acid in this composite hydrogel.The high degree of crystallinity of the titanium dioxide in hydrogel was anatase,which was measured by the X-ray diffraction method.The FT-IR analysis showed that no groups of materials were changed in the progress of hydrogel formed,which indicated that the composite hydrogel was indeed formed by the physical cross-linking.The composite hydrogel had excellent water absorption and a large saturated water absorption rate proportion of up to 1500%,thus the hydrogel can be used as a water absorbing material.Furthermore,the composite hydrogel as catalysis was used to degrade simulation dye effluents such as methylene blue irradiate with natural light.The effect of photo catal
作者
张辉
江健平
李静
李由
周亮
高慧
刘盛全
ZHANG Hui;JIANG Jianping;LI Jing;LI You;ZHOU Liang;GAO Hui;LIU Shengquan(School of Forestry and Landscape Atchitecture,Anhui Agricultural University,Hefei 230036,China)
出处
《林业工程学报》
CSCD
北大核心
2020年第2期76-81,共6页
Journal of Forestry Engineering
基金
国家重点研发计划子课题(2017YFD0600201)
安徽省教育厅自然科学重点项目(KJ2019A0200)
国家级大学生创新创业训练项目(201910364020)
关键词
壳聚糖
丙烯酸
二氧化钛
复合水凝胶
光催化
chitosan
acrylic acid
titanium dioxide
composite hydrogel
photocatalytic
