壳聚糖整理棉织物透湿和抗折皱性能研究

使用不同分子量的壳聚糖对棉织物进行整理.借助FTIR分析了壳聚糖处理前、后的棉纤维结构,并对织物透湿和抗折皱性能进行了测试.结果表明,当壳聚糖分子量小于2.5×104时,随着壳聚糖浓度的增加透湿量逐渐增大,浓度为0.60%时透湿量达到最大值,此后透湿量又随着浓度的增加而减小;采用吸尽法处理的棉织物透湿性能整体上要好于浸轧法.低分子量壳聚糖处理的棉织物,其抗折皱回复性能明显好于高分子量的壳聚糖,而且随着壳聚糖浓度的增加,折皱回复率先增大后减小.     

壳聚糖接枝改性单羧基棉织物的结构及性能

采用HNO3/H3PO4-NaNO2氧化体系选择性氧化棉织物得到单羧基纤维素,然后与壳聚糖溶液酰胺交联反应,使壳聚糖化学键合单羧基棉织物。研究HNO3/H3PO4-NaNO2氧化时间对单羧基棉织物羧基含量、断裂强力及壳聚糖接枝后棉织物增重率的影响,得出氧化时间在45min时,壳聚糖接枝棉织物的最大增重率为5.52%。运用固相CP/MAS 13C NMR、FT-IR、SEM和XRD等测试分析,结果表明,HNO3/H3PO4-NaNO2体系将棉纤维葡萄糖单元中C6位伯羟基选择性氧化成羧基,壳聚糖分子中的氨基与氧化棉织物上的活性羧基反应形成C-N酰胺化学键,壳聚糖在织物表面共价交联成膜。壳聚糖接枝反应后,单羧基棉织物的结晶度从65.37%下降到60.86%,壳聚糖改性棉织物的断裂强力、白度及毛细效应有所减小,但折皱回复角明显提高。     

壳聚糖-氧气等离子体对棉织物抗皱及透湿整理

对比分析了经单独壳聚糖整理液整理、壳聚糖整理液-氧气等离子体联合整理(先采用壳聚糖整理液对纯棉坯布进行整理,再进行氧气等离子体处理)后棉织物的抗皱性、吸湿性、耐水洗性等;探讨了壳聚糖整理液-氧气等离子体联合整理后焙烘温度、焙烘时间等工艺参数对织物折皱回复角、断裂强力保留率、白度的影响.得出了棉织物壳聚糖-氧气等离子体抗皱整理的最佳工艺.结果表明:经氧气等离子体处理后,能提高棉织物的拉伸断裂强力,明显改善织物的吸湿性,提高服用舒适性,并且织物整理的耐久性较好.     

Induced expression of the Candida albicans multidrug resistance gene CDR1 in response to fluconazole and other antifungals

The Candida albicans CDR1 gene encodes a member of the ABC-type family of multidrug transporters which has been shown to be involved in azole resistance. Using an in-frame gene fusion between the CDR1 open reading frame and the green fluorescent protein allele yEGFP3, an optimized derivative for its use in C. albicans, we show here how the CDR1-yEGFP3 gene expression is induced in response to azoles as well as to other structurally unrelated drugs like cycloheximide. Moderate increases were observed for calcofluor, canavanine, 5′-fluorcytosine, cilofungin and caffeine, while no induction was found for the antifungals benomyl and amphotericin B or hydrogen peroxide at subinhibitory concentrations. The use of confocal microscopy enabled us to localize the Cdr1p fusion protein at the cell periphery, thus suggesting a cytoplasmic membrane localization. These results suggest deregulation of CDR1 gene as a putative mechanism for the generation of azole resistance in this clinically important pathogenic fungus. © 1998 John Wiley & Sons, Ltd.     

棉织物等离子体/柠檬酸的抗皱整理初探

采用低温等离子体/柠檬酸处理方法,对棉织物进行抗皱整理.研究了等离子体处理在棉织物抗皱整理中的加工顺序对棉织物性能的影响.以整理后织物的拉伸断裂强力、强力保留率、折皱回复角和白度等指标进行测试比较,说明该方法能在一定程度上提高整理织物的拉伸断裂强力和强力保留率,得出低温等离子体/柠檬酸整理织物的最佳工序为:浸轧整理液→烘干→焙烘→等离子体处理→水洗→晾干→烘干.     

Application of polyethylene glycol,cetrimide, chitosan and their mixtures on cotton muslin fabric to improve rot resistance,antimicrobial property and its salt-free reactive dyeing

In the present work, cotton muslin fabric is treated with eco-friendly antimicrobial agents in order to observe the effect of those chemicals on the rot resistance properties, physical appearance, important textile-related mechanical properties and dyeability with reactive dyes. The cotton fabric has been treated with polyethylene glycol (PEG 200), cetrimide and chitosan individually and their blends, in the presence of citric acid and sodium hydrogen phosphate as mixed catalyst to investigate the effect of such treatment on fabric properties of treated cotton mentioned above. Amongst all individual and combined applications of above said chemicals, it is observed that treatment with a mixture of chitosan and PEG is showing good result in terms of improvement in rot resistance performance and an optimum balance in other textile-related mechanical and appearance properties indicating lowest degradation against microbial attack. A series of experiments were undertaken with varying percentage of both the chemicals to arrive at the optimum ratio of mixture of PEG and chitosan and compared with such effect for treatment with conventional quaternary ammonium compound EPTAC. This treatment shows much balance results and also creates a newer provision of salt-free reactive dyeing of such treated/cationized cotton muslin fabric by unconventional reactive dyeing in acid bath after such chemical treatment/modifications.     

The removal of impurities from gray cotton fabric by atmospheric pressure plasma treatment and its characterization using ATR-FTIR spectroscopy

Gray cotton fabric shows hydrophobic characteristics due to presence of non-cellulosic impurities in outermost layers of cotton fiber. In the present study, atmospheric pressure plasma treatment for the removal of the non-cellulosic impurities from gray cotton fabric is investigated. Gray cotton fabric is treated with air dielectric barrier discharge at different time interval, and characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and scanning electron microscopy (SEM). Different species formed in plasma are identified using optical emission spectroscopy. The results clearly show that the plasma treatment improves wettability of gray cotton which is due to the removal of non-cellulosic impurities and due to the formation of polar carboxylate group. Removal of wax after plasma treatment is clearly reflected in ATR-FTIR spectra as disappearance of symmetric and asymmetric stretching of alkyl group at 2852.24 and 2917.81?cm^?1. Further, ATR-FTIR spectroscopy provides a fast and satisfactory assessment of removal of impurities from cotton surface when untreated and plasma-treated cotton fabric is exposed to HCl vapor and subsequently spectra are collected. We observed a strong carboxyl peak is induced at 1749?cm^?1 in case of untreated cotton. While for plasma-treated cotton fabrics substantial variation in the intensity of 1641 and 1749?cm^?1 peak is observed with increase in plasma treatment time. The morphological changes observed by SEM are in accordance with ATR-FTIR results. The results are compared with conventionally (alkaline scouring) treated cotton fabric. The study reveals that atmospheric pressure plasma has potential to become dry and environment friendly process to improve wettability of gray cotton fabric.