甲壳素和甲壳胺纤维质量的影响因素

概述了影响甲壳素和甲壳胺纤维质量的因素,如甲壳素和甲壳胺的品质、纺丝原液的溶剂选择及浓度的确定、凝固浴的确定;简述了通过化学改性来改善甲壳素和甲壳胺纤维性能;介绍了国内外为改善纤维质量所作的最新研究。     

间接法生产甲壳素纤维

由于天然甲壳素结晶度高,在湿法纺丝过程中溶解甲壳素时需要使用价格较高的有机溶剂。甲壳素脱乙酰基后得到的甲壳胺可以很方便地溶解在稀醋酸水溶液中,经喷丝孔挤出后用稀碱中和沉淀即可得到甲壳胺纤维。在甲壳胺纤维上加上乙酰基后可以得到再生甲壳素纤维。介绍了在用乙酸酐处理甲壳胺纤维制备再生甲壳素纤维过程中,反应时间、反应温度、乙酸酐用量对乙酰化的影响。     

纺织用甲壳素纤维的研究进展

甲壳素及甲壳胺纤维具有生物可相容性、生物可降解性、无毒性及良好的抗菌性能等特点,已经被应用于纺织服装行业以及医用卫生材料的生产中。介绍了纺织用甲壳素及甲壳胺纤维的制备方法及几个国内外甲壳素纤维品种,分析了甲壳素纤维的应用领域。     

甲壳素与甲壳胺纤维1.纤维的制备

甲壳素和甲壳胺是广泛存在于动物和植物中的天然高分子材料。近年来,这两个高分子的生物相容性、生物可降解性、对伤口愈合的促进性能和其它一些优异性能在科技和工商界引起了广泛的重视。作为一种天然再生资源,它们在许多领域内都有很广的应用和开发潜力。总结了甲壳素和甲壳胺纤维的生产条件。     

甲壳素与甲壳胺纤维4.纤维在生物医药领域中的应用

甲壳素和甲壳胺是广泛存在于动物和植物中的天然高分子材料。近年来,这两个高分子的生物相容性、生物可降解性、对伤口愈合的促进性能和其它一些优异性能在生物医药领域引起了重视。甲壳素和甲壳胺纤维既具有天然高分子的生物活性,又有纤维材料的特性,在手术缝合线、医用敷料、人工皮肤、硬组织修复材料、人工肾膜、抗菌材料、保健内衣面料、药物缓释等材料中得到了广泛的应用。     

以天然高分子为原料的生物降解性纤维的开发

本文就甲壳胺及明胶的纤维化进行一些介绍。1甲壳胺纤维甲壳胺溶于弱酸,以此作为纺丝液,可用碱-醇体系作凝固浴或铜-氨体系作凝固浴进行纺丝。但是,纤维的脱碱或脱铜费时,而且凝固液是强碱性,在操作安全性和废液处理方面都有问题。我们在寻找甲壳素的缓和溶剂的过程中,发现了氯     

甲壳胺纤维的改性处理

近年来甲壳胺纤维在抗菌纺织品、医用敷料等产品中得到广泛的应用。这些产品利用了甲壳胺纤维的广谱抗菌性能,以及它的吸湿性和促进伤口愈合的性能。由于甲壳胺的分子结构中有反应活性很高的氨基,通过对氨基的化学改性可以得到具有特殊功能的改性甲壳胺纤维。介绍了近年来开发的几种典型的功能性改性甲壳胺纤维。     

甲壳胺纤维的螯合性能

把甲壳胺纤维与CuSO4和ZnSO4的水溶液处理后,通过控制处理的时间可以使纤维吸附不同含量的金属离子。研究了纤维上的金属离子的含量对纤维的物理机械性能的影响。结果表明,吸附金属离子后,纤维的干强和湿强都有明显的增加。纤维上的金属离子可以被EDTA的水溶液洗去,从而可以使纤维重复地应用于废金属离子的回收利用。把甲壳胺纤维进行乙酰化处理后,纤维可以在固体状态下转化成甲壳素纤维。实验结果表明,乙酰化后的纤维失去了它们对金属离子的螯合性能,从而证明了甲壳胺纤维的螯合性能主要来自于纤维上的自由胺基团。     

甲壳素与甲壳胺纤维2.纤维的性能

甲壳素和甲壳胺纤雏既具有纤维材料的强度、桀软性、高表面积和形成各种类型的织物的能力,又有这两种天然高分子所特有的生物相容性、生物可降解性、广谱抗菌性、凝血作用以及促进伤口复愈、调节血脂、降低胆固醇、增强免疫和抗肿瘤等多种生理活性作用。     

化纤园地

甲壳素和甲壳胺纤维的技术进展用甲壳素和甲壳胺制成的纤维,具有抑菌、镇痛、吸湿、止痒等功能。在医疗领域中,可用于生产缝合线、制作人体皮肤烧伤,烫伤用纱布和非织造布等。在工业领域中可作为吸收放射性的罩布,超级话筒布,特殊抗玷污罩布等。在纺织品方面可制成尿布、婴儿服     

不同虾壳部位中的甲壳素和壳聚糖

用EDTA的方法分别从虾壳的不同部位:虾头、虾身、虾足和虾头内容物三部分制备甲壳素和壳聚糖,对三组试样的性能参数如脱乙酰度和相对分子量等进行分析研究。得出结论:由虾壳不同部位所制得的甲壳素和壳聚糖结构基本一致,但其脱乙酰度和相对分子量有较大差别,其物化性质也有所不同。在三组试样中,以从虾头壳制备的甲壳素和壳聚糖的相对分子质量为最大;而脱乙酰度则以从虾足和虾头内容物中制得试样较高。     

虾壳制备甲壳素和壳聚糖的研究

用EDTA的方法分别从虾壳的不同部位:虾头、虾身、虾足和虾头内容物三部分制备甲壳素和壳聚糖,对三组试样的性能参数如脱乙酰度和相对分子量等进行分析研究。得出结论:由虾壳不同部位所制得的甲壳素和壳聚糖结构基本一致,但其脱乙酰度和相对分子量有较大差别,所以其物化性质也有所不同。特别值得一提的是,在三组试样中,以从虾头壳制备的甲壳素和壳聚糖的相对分子质量为最大;而脱乙酰度则以从虾足和虾头内容物中制得试样较高。     

Interaction of lead and chromium with chitin and chitosan

The interaction of the natural marine polymer chitin and its deacetylated derivative chitosan with lead and chromium has been investigated. The uptake of lead and chromium was determined from changes in concentration as measured by atomic absorption spectroscopy. A significant uptake of Pb(II) on both chitosan and chitin was observed. However, the uptake of Pb(II) on chitin was approximately 21% of that on chitosan. The number of Natoms in chitin and chitosan and per number of Pb(II) ions sorbed was 115 and 29, respectively. The number density of flakes observed in the scanning electron microscope and characterized by an intense Pb signal in energy dispersive analysis of x rays (EDAX) was greater on the surface of chitosan [containing 1.7 × 10^?4 mole Pb(II)/g chitosan] than chitin [containing 3.5 × 10^?5 mole Pb(II)/g chitin] after equilibration with Pb(II) solution. The bonding state of lead on chitosan as determined by electron spectroscopy for chemical analysis (ESCA) is similar to the bonding of lead in PbO based on the Pb 4f_7/2 binding energy. A significant shift in the O 1s binding energy from 532.2 to 531.4 eV was observed for chitosen after equilibration with Pb(II) solution. The caculated values of the N/Pb ratio from ESCA spectra were 0.5 and 11, for chitosan and chitin, respectively. A significant uptake of Cr(III) on chitosan was observed and a significant increase in the pH of solutions of Cr(III) on equilibration with chitosan occurred. A high number density of nodules characterized by an intense Cr signal in EDAX was observed in chitosan [containing 2.5 mole Cr(III)/g chitosan] after equilibration with Cr(III) solution. The calculated values of the N/Cr ratio from ESCA spectra was 18 for chitosan.     

Current state of chitin purification and chitosan production from insects

Chitin, and especially its deacetylated variant chitosan, has many applications, e.g. as carrier material for pharmaceutical drugs or as a flocculant in wastewater treatment. Despite its versatility and accessibility, chitin, the second most abundant polysaccharide on Earth, has so far been commercially extracted only from crustaceans and to a minor extent from fungi. Insects are a viable alternative source of chitin, but they have not been exploited in the past due to limited availability. Today however, for the sustainable production of animal feed, insect farming is being developed substantially. The availability of large quantities of insect biomass and chitin-rich side products such as exuviae and exoskeletons has been increasing. This review provides an overview of recently published studies of chitin extraction from insects, its subsequent conversion into chitosan and the primary analytical methods used to characterize insect-based chitin and chitosan. We have discovered a large number of research articles published over the past 20 years, confirming the increased attention being received by chitin and chitosan production from insects. Despite numerous publications, we identified several knowledge gaps, such as a lack of data concerning chitin purification degree and chitosan yield. Furthermore, analytical methods used to obtain physicochemical characteristics, structural information and chemical composition meet basic qualitative requirements but do not satisfy the need for a more quantitative evaluation. Despite the current shortcomings that need to be overcome, this review presents encouraging data on the use of insects as an alternative source of chitin and chitosan in the future. © 2020 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI).     

壳聚糖作为分离膜材料的研究进展

介绍了甲壳素和壳聚糖的制备、结构和性质,对壳聚糖在反渗透膜、渗透蒸发膜、超滤膜、纳滤膜、亲和膜、离子交换膜、气体分离膜等方面的应用进行了综述。     

甲壳素及其衍生物纤维的研究进展

回顾了用不同溶剂溶解甲壳素并纺制纤维的尝试,以及壳聚糖乙酸水溶液的纺丝工艺和通过后处理提高壳聚糖纤维强度的方法;对甲壳素和壳聚糖的化学改性和衍生物纤维的制备作了综述。     

Hydrogels Based on 2-Hydroxyethylmethacrylate and Chitosan: Preparation,Swelling Behavior,and Drug Delivery

The authors report preparation of chitosan by deacetylation of chitin extracted from shrimp shells. The quality of chitosan depended on the chemical extraction process, the concentration of chemicals used, soaking time, sequence of deproteination, decalcification, and deacetylation. Hydrogels composed of hydroxyethylmethacrylate and chitosan were subsequently prepared and their swelling and ibuprofen delivery kinetics at various chitosan concentrations were studied. The swelling properties of the network varied with the chitosan concentration. Furthermore, the swelling process followed second-order kinetics, while ibuprofen diffusion into the hydrogel showed Fickian behavior.     

改性甲壳素和壳聚糖在食品中的应用

本文介绍了甲壳素和壳聚糖及其有关化学改性方法,阐述了水溶性甲壳素和壳聚糖衍生物的制备方法及其在食品工业中作食品添加剂的应用。     

降解制备壳寡糖研究进展

壳寡糖因具有多种生物活性,成为国内外研究的热点,其制备技术是壳聚糖产业研究开发的重点领域。壳寡糖的制备方法主要有化学法、酶解法和综合法。本文对壳寡糖的制备方法及其作用机理进行了综述。