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新型两性壳聚糖衍生物的制取及应用研究 总被引:4,自引:0,他引:4
用氯乙酸和2,3-环氧丙基三甲基氯化铵对壳聚糖进行改性,采用不同反应条件制备了一系列不同取代度的O-羧甲基-N-羟丙基三甲基氯化铵壳聚糖。通过红外光谱对结构进行表征,IR谱图分析证实羧甲基以0位上为主,季铵盐阳离子基以N位上取代为主。研究了产物的取代度、吸湿保湿性、抗菌性、pH稳定性及与表面活性剂的配伍性,结果表明具有良好的吸湿保湿性。 相似文献
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不同取代度壳聚糖季铵盐的制备及其热稳定性研究 总被引:3,自引:0,他引:3
制备了不同取代度的壳聚糖季铵盐(羟丙基三甲基氯化铵壳聚糖),利用单因素实验分析了制备条件,采用热重分析探讨了壳聚糖季铵盐的热降解温度。结果表明,壳聚糖季铵盐的最佳制备条件为环氧丙基三甲基氯化铵(ETA)与壳聚糖的比为3,水与异丙醇的比为3,反应温度为80℃,反应体系的pH值为6.0。壳聚糖季铵盐与壳聚糖相比,热稳定性下降,随着壳聚糖季铵盐取代度的增加,初始降解温度(T0)、最大降解速率温度(Tp)和终止降解温度(Tf)均逐渐降低。同时,从初始降解温度到最大降解速率温度的时间也随着取代度的增加而减少。 相似文献
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以环氧氯丙烷和三乙胺为原料合成了缩水甘油基三乙基氯化铵,并用其对壳聚糖进行了交联改性。产品结构经FT IR、HRTEM进行了表征;考察了反应时间、反应温度及pH值对壳聚糖交联取代度的影响;探讨了交联取代度对产品热稳定性和水溶性的影响。结果表明,缩水甘油基三乙基氯化铵成功地对壳聚糖进行了交联改性;pH≈7、反应温度90℃、反应时间14h时,交联壳聚糖的取代度最大可达93.4%;交联壳聚糖的热稳定性比壳聚糖有所降低,且随取代度的增大而下降;水溶率随取代度的增大而升高。 相似文献
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壳聚糖季铵盐(HTCC)是以壳聚糖为基本原料,将壳聚糖与2,3-环氧丙基三甲基氯化铵(GTA)发生醚化反应的产物。壳聚糖季铵化改性后,不仅提高了壳聚糖的溶解性,而且在一定程度上增加了其抑菌性。优化了制备壳聚糖季铵盐的几项基本工艺参数,确定了壳聚糖季铵盐制备的最佳工艺参数为:GTA与壳聚糖的质量比为4∶1,反应温度为70℃,反应时间为9h,p H值为7.0,产物取代度最高可达85.1%。将制备的壳聚糖季铵盐产品用于咸鸭蛋和草莓的保鲜,取得了较好的保鲜效果。 相似文献
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采用氯乙酸、丙烯酸和2,3-环氧丙基三甲基氯化铵对壳聚糖(CTS)改性,制得羧甲基-季铵壳聚糖(CMQAC)和羧乙基-季铵壳聚糖(CEQAC),并通过IR、1H NMR、XRD对产物进行了结构确证。用静态阻垢的方法对两性壳聚糖衍生物阻硫酸钙垢的性能进行了评价,结果表明两性壳聚糖用量为16 mg/L、[Ca2+]〈2000 mg/L、[SO42-]〈4800 mg/L时,阻垢率可达到100%。用小瓶测试法测定不同季铵取代度(DS)的两性壳聚糖对异养菌的杀菌效果。研究结果表明,在用量为30 mg/L时,CMQAC季铵取代度为0.73时杀菌率为99.7%,CEQAC季铵取代度为0.50时杀菌率为99.2%,改性后壳聚糖衍生物的阻垢和杀菌性能与壳聚糖相比有了明显提高。 相似文献
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在酸性条件下,以壳聚糖与环氧季铵盐为原料反应得到水溶性良好的产物N-(2-羟丙基三甲基氯化铵)壳聚糖(HTCC),再用实验室自制的环氧海因改性,得到O-羟丙基(5,5-二甲基海因)-N-(2-羟丙基三甲基氯化铵)壳聚糖衍生物(GH-HTCC),用 FTIR、1H NMR、UV-VIS和EA 等对产物进行表征。抗菌实验结果表明,产物对两种菌种都有一定的抗菌活性,对金黄色葡萄球菌的抗菌活性优于大肠杆菌;GH-HTCC的抗菌活性优于HTCC,并随环氧海因取代度的增加而增强;低浓度的乙二胺四乙酸(EDTA)增强了HTCC和GH-HTCC的抗菌活性,而高浓度的EDTA在一定程度上抑制了二者的抗菌活性。 相似文献
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壳聚糖季铵盐的合成及其对鞣酸的絮凝性能 总被引:3,自引:0,他引:3
通过引入季铵盐基团的方法对壳聚糖进行改性得到完全溶于水的壳聚糖季铵盐,IR谱图表明取代反应主要发生在壳聚糖的氨基上。以中药药液中的主要杂质之一鞣酸为对象进行了絮凝试验,结果显示其鞣酸去除率,明显高于壳聚糖。同时壳聚糖季铵盐絮凝剂投加量适用范围更宽,有利于实际使用。 相似文献
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采用异丙醇为溶剂,以壳聚糖(CTS)、2,3-环氧丙基三甲基氯化铵(GTA)为原料,用环氧衍生物开环法制备了壳聚糖季铵盐(HACC).通过单因素实验,研究了反应物摩尔比、反应时间、反应温度等因素对产物取代度的影响.结果表明,制备壳聚糖季铵盐的最优工艺为:ncrs∶nGrA =1∶4,反应时间8h,反应温度75℃,反应pH值为7,碱化时间14h,壳聚糖分子量3.2×105,反应体系含水率20%.通过红外光谱、扫描电镜、热重仅对壳聚糖、壳聚糖季铵盐的结构、外观形貌以及热稳定性进行了表征与分析,结果表明壳聚糖季铵化改性以N-取代为主,改性后外貌和粒度有了明显变化,且热稳定性降低. 相似文献
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The water-soluble N-(2-hydroxy)propyl-3-trimethylammonium chitosan chloride (HTCC) was prepared by chitosan and glycidyl trimethyl ammonium chloride. Fourier-transform infrared spectroscopic analysis spectrum confirmed that glycidyl trimethyl ammonium chloride was grafted to the amino groups of chitosan via substitution reaction (Zhao et al., Int J Pharm 2010, 393, 268; Montazer and Afjeh, J Appl Polym Sci 2007, 103, 178). The obtained chitosan derivative was used to modify cotton fabrics for improving aqueous pigment-based inkjet printing and antibacterial properties. Scanning electron microscope images showed that HTCC was adhered onto the cotton fabrics surface and formed film structure. The K/S value on printed cotton substrates increased from 3.20 to 4.87, which indicated that higher color yield was achieved in this way. Modified samples performed better crocking fastness and laundering fastness than the control cotton fabrics. The line definition of modified cotton fabrics respectively, improved 16.5% and 12.6% in the warp and weft direction as the specified line width was 0.5 × 103 μm. Samples also showed good antibacterial potential, the inhibitory rate for Staphylococcus aureus and Escherichia coli were both more than 95% when the concentration of HTCC used in the pretreatment solution was 0.8%. The antibacterial effect was found to be durable for 20 laundering cycles. However, the hand feeling of modified cotton fabrics presented a slight decrease. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
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Zhao‐Sheng Cai Zhan‐Qian Song Chun‐Sheng Yang Shi‐Bin Shang Yan‐Bai Yin 《应用聚合物科学杂志》2009,111(6):3010-3015
N,O‐(2‐carboxyethyl)chitosan (N,O‐2‐CEC) was prepared from chitosan with 3‐chloropropionic acid as modifying agent and NaOH as binding‐acid agent. 2‐Hydroxypropyl dimethylbenzylammonium N,O‐(2‐carboxyethyl) chitosan chloride (HPDMBA‐CEC) was obtained by the reaction of N,O‐2‐CEC with glycidyl dimethyl benzyl ammonium chloride (GDMBA) using NaOH as catalyst. The structures of chitosan derivatives were characterized by FTIR, 1H NMR, and gel permeation chromatography. The antimicrobial activity of HPDMBA‐CEC was evaluated against a Gram‐negative bacterium Escherichia coli (E.coli) and a Gram‐positive bacterium Staphylococcus aureus (S. aureus). Compared with CTS, N,O‐2‐CEC, and HPDMBA‐CTS, HPDMBA‐CEC had much stronger antimicrobial activity, and this activity increased with increasing substitution degree of quaternary ammonium group (DQ). When the substitution degree of carboxyethylation (DS of CE) was 0.72 and DQ was 0.60, the minimum inhibitory concentrations (MICs) of HPDMBA‐CEC were 3.1 and 6.3 μg/mL against S. aureus and E. coli, respectively. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献