摘要:以2,3-环氧丙基三甲基氯化铵(GTMAC)为改性剂对壳聚糖(CTS)进行季铵化改性,制备适当取代度的2-羟丙基三甲基氯化铵壳聚糖(HTCC)。以HTCC为活性功能层,聚醚砜(PES)超滤膜为支撑层,环氧氯丙烷(ECH)为交联剂,制备荷正电壳聚糖复合纳滤膜,并探讨了ECH浓度、HTCC浓度等条件对膜性能的影响。通过扫描电镜对膜的结构进行了表征,并考察了膜的各项性能。实验结果显示,壳聚糖分子的亲核中心-NH2上的氢已被季铵盐部分取代;HTCC/PES复合膜的纯水渗透系数为19.1 L·h-1·m-2·Mpa,截留分子量为977左右,对无机盐的截留顺序为MgCl2 >NaCl >KCl >MgSO4 >Na2SO4 > K2SO4,呈现荷正电纳滤膜的特征;复合膜具有良好的机械性能(机械强度234.53Mpa,断裂伸长率20.75%)。63754
毕业论文关键词:壳聚糖;2-羟丙基三甲基氯化铵壳聚糖;环氧氯丙烷;荷正电纳滤膜;膜性能
毕业设计说明书(论文)外文摘要
Title Preparation and Properties of quaternized chitosan (HTCC)/ polyethersulfone (PESF) composite nanofiltration membrane
Abstract
N-(2-hydroxy)-propyl-3-trimethylammonium chloride chitosan (HTCC) with different substitution degrees were prepared by means of quaternization between chitosan and glycidyl trimethyl ammonium chloride (GTMAC) in a homogeneous system. Then, a novel composite nanofiltration (NF) membrane was prepared using HTCC as active layer, polyethersulfone (PESF) ultrafiltration (UF) membrane as support layer and epichlorohydrin (ECH) as cross-linking reagent. The effects of membrane preparation conditions such as HTCC concentration, ECH concentration, etc on membrane performance were investigated. The structure characteristics of the resultant NF membrane was observed by scanning electron microscope. The pure water permeability of this membrane is 19.1 L·h-1·m-2·Mpa and the cut-off molecular weight of the composite membrane is about 977. The order of rejection to different salt solutions is MgCl2>NaCl>KCl>MgSO4>Na2SO4 > K2SO4, revealing the characteristic of positively charged NF membranes. The membrane also has good mechanical properties (mechanical strength 234.53, elongation at break 20.75%).
Keywords: Chitosan; Hydroxypropyl-trimethyl ammonium chloride chitosan; epichlorohydrin; Positively charged composite NF membrane; membrane properties
目 录
1 绪论 5
1.1壳聚糖及其改性 5
1.2 羟丙基三甲基氯化铵壳聚糖 6
1.3 改性壳聚糖复合膜 6
1.3.1 季铵盐壳聚糖复合膜 6
1.3.2 羧甲基壳聚糖复合膜 7
1.4 荷正电壳聚糖纳滤膜的制备 8
1.4.1 复合法制备荷正电纳滤膜 8
1.4.2 改性壳聚糖制备荷正电纳滤膜 8
1.4.3 共混法制备壳聚糖纳滤膜 9
1.5 选题目的与意义 9
2 实验部分 10
2.1 实验试剂与仪器 10
2.2 羟丙基三甲基氯化铵壳聚糖(HTCC)的制备 11
2.2.1 实验装置 11
2.2.2 实验原理 11
2.2.3 实验方法 12
2.3 壳聚糖和羟丙基三甲基氯化铵壳聚糖的表征