【作者】 李少光；

【导师】 査飞；

【作者基本信息】 西北师范大学 ， 高分化学与物理， 2008， 硕士

【摘要】 论文在综述壳聚糖的改性及其固载环糊精研究进展的基础上,主要作了以下工作:1.以壳聚糖和戊二醛为原料,采用O/W反相乳液方法制备了壳聚糖微球,然后使用6-亚甲基二异氰酸酯为交联剂,将功能基团β-环糊精固载在壳聚糖微球上,得到一种新型的壳聚糖固载β-环糊精微球。苯酚-硫酸法确定β-环糊精的表观固载量为4.3%。FT-IR、TG-DTA和XRD表明,壳聚糖固载β-环糊精微球的结构、热稳定性、结晶度等性质变化较大。2.应用制备的壳聚糖固载β-环糊精微球做吸附剂,研究了对对苯二酚的吸附行为。在pH=7.0、操作温度303K、振荡时间10h的条件下,聚糖固载β-环糊精微球对对苯二酚的理论最大吸附量达到23.31mg/g。该吸附剂对对苯二酚的吸附可以用Langmuir和Freundlich方程来描述,热力学分析结果表明吸附为一自发的放热过程。3.以β-环糊精为原料,用环氧氯丙烷对其进行交联聚合,制备了水溶性环糊精聚合物,然后使用具有双官能团的γ-缩水甘油基醚氧基-3-甲氧基硅烷,采用溶液蒸发的方法,实现对壳聚糖的交联和对环糊精聚合物的固载,制备了壳聚糖固载环糊精聚合物薄膜。用FT-IR、XRD、TG和SEM对产物的结构与性质进行了表征。在投料比(以γ-缩水甘油基醚氧基-3-甲氧基硅烷环氧基团和壳聚糖氨基的摩尔比计)为1:1,303K时蒸发6h,制得的壳聚糖固载β-环糊精多孔膜微孔规则、分布均匀(1-3μm),饱和吸水率为120.52%,β-环糊精表观固载量为78mg/g。4.用制得的壳聚糖固载β-环糊精多孔膜做吸附剂,研究了对水中对苯二酚的吸附行为,吸附容量随溶液浓度和pH的增大而增加,吸附在2h内可达平衡;动力学研究表明壳聚糖固载环糊精多孔膜对对苯二酚的吸附为准二级过程,以化学吸附为速率控制步骤,吸附表观活化能为70.0kJ/mol。更多还原

【Abstract】 Based on the review of the development of modification of chitosan and its support of cyclodextrins, the dissertation included following contents:1. Glutaraldehyde activated chitosan beads were prepared by an O/W inverse emulsion polymerization andβ-cyclodextrin was cross-linked to the beads by 1, 6-hexamethylene diisocyanate. The content of theβ-CD moiety in the beads is 4.3%, which was determined by the phenol–sulfuric acid method. The beads were characterized by the methods of IR, XRD and TG-DTA. It shows significant changes in the molecular constitutions, crystalline and thermal properties.2. The adsorption property of hydroquinone by the modified chitosan supportedβ-cyclodextrin synthysized was studied with spectrophotometry. The adsorption capacity increases with the increasing of temperature and the pH. The theoretic amount of the hydroquinone adsorbed can be up to 23.31mg/g under the conditions at temperature of 303K, pH=7.0 and the adsorption time of 10h. The adsorption process can be simulated by Langmuir isotherm and Freundlich isotherm. Thermodynamic parameters such as free energy change, enthalpy change and entropy change were calculated. The adsorption seems to be a spontaneous and endothermic process.3. The water-solubleβ-cyclodextrin polymer was synthesized by a limited polycondensation ofβ-cyclodextrin with epichlorohydrin. Afterwards, porous structured chitosan-β-cyclodextrin membrane was synthesized by incorporatingβ-cyclodextrin polymer synthesized as the functional reagent and usingγ-glycidoxypropyltrimethoxysilane as crosslinking agent. Compared with chitosan itself, the synthesized membrane shows the significant changes in the molecular constitutions, the crystallinity and the thermal properties. Under a optimal condition of mol ratio (epoxy groups ofγ-glycidoxypropyltrimethoxysilane to free amino groups of chitosan) of 1:1, evaporated time of 6h at 333K, the membrane hassmoother surface and the micropore is more regular (1-3μm), with swelling ratio of 120.52% and the content of theβ-cyclodextrin of 78mg/g.4. The behavior of citosan-β-cyclodextrin membrane synthesized for the adsorption of hydroquinone in water was studied. The effects of the initial concentration of adsorbate and the pH on the adsorption were investigated by the spectrophotometry. The adsorption equilibrium can be reached within 2h. The adsorption capacity increases with the increasing of initial concentration and the pH value. Kinetic studies show the adsorption is a pseudo-second order process. The adsorption is endothermic and chemically activated reaction with activation energy of 70.0 kJ/mol.更多还原