U.S.-Egypt Cooperative Research: Ionic Crosslinking - A Novel Method for Fabric Stabilization

项目描述：该项目支持北卡罗来纳州立大学（NCSU）纺织化学系C. Brent Smith博士和埃及开罗国家研究中心Mohamed Hashem博士的合作研究。pi将考虑新的化学系统来处理棉花，通过使用不释放甲醛的离子交联剂，在不使用甲醛等有害化学物质的情况下提高性能。目标是为纤维素织物提供更好的干湿折皱恢复（WRA），以及其他优势，如抗菌活性和增强的可染性。研究将涵盖离子交联方法，以产生抗皱耐压效果的棉花。这包括用阴离子材料处理棉花，然后与聚阳离子反应；或者与阳离子材料反应，然后加入聚阴离子。他们将纤维素与氯乙酸（CAA）反应制备阴离子棉，将负离子位点附着在纤维素纤维上，并用各种阳离子处理阴离子纤维素，以提高WRA性能。他们还会用3-氯-2-羟丙基三甲基氯化铵（CHTAC）处理纤维素织物，将正离子附着在纤维上，然后用各种负离子处理织物。知识优势：当用甲醛基交联剂处理时，纤维素织物表现出更好的机械稳定性，折痕恢复角（CRA）和耐用的熨烫性能。但树脂处理也会导致织物失去强度，随后释放甲醛，一种已知的人类致癌物。pi已经发现，离子交联可以用来稳定纤维素，使用高分子量的反应性离子材料，不释放危险的反应性化学物质，但同时提供出色的CRA和完全的强度保留在处理过的货物。pi计划研究这种稳定的物理和化学机制，并测试各种离子交联剂和在纤维素纺织材料中产生这些交联的方法。这需要：1)在化学实验室进行基础研究，2)在商业生产环境中实施最佳化学原理。研究结果有可能对环境产生积极影响。更广泛的影响：为了稳定几乎在任何地方广泛使用的棉纺织产品，它们普遍使用树脂处理，然后释放甲醛，一种已知的人类致癌物质。这些树脂也会造成强度损失和颜色变化。纺织品生产商的长期目标是生产易于护理，抗皱纤维织物，而不使用甲醛为基础的反应物。此外，棉花上的离子电荷的存在可以使具有相反电荷的染料消耗得更高。这为棉纺商面临的两个最大问题提供了一个可能的解决方案：(1)纺织染色废水中过量的颜色浪费和颜色污染；(2)目前用于棉纺制品染色的大量盐造成的水生毒性。该项目为埃及科学家提供了一个机会，可以扩展一种可以长期为他们的国家服务的专业知识，而且由于埃及是棉花生产国，这可能会导致该国的经济和技术进步。该项目将包括对至少一名博士后的支持，也将包括NCSU的研究生。pi将与其他学术研究人员以及化学品制造商和纺织品制造商进行互动。该项目得到了美国-埃及联合基金项目的支持，该项目向两国的科学家和工程师提供赠款，以开展这些合作活动。

0513828SmithDescription: This project supports a collaborative research between Dr. C. Brent Smith, Department of Textile Chemistry, North Carolina State University (NCSU) and Dr. Mohamed Hashem, National Research Center, Cairo, Egypt. The PIs will consider new chemical systems for treating cotton, that give enhanced performance without using harmful chemicals like formaldehyde, by using ionic crosslinking agents that don't release formaldehyde. The goal is to provide better wet and dry wrinkle recovery (WRA) for cellulosic fabrics, as well as other advantages, such as antimicrobial activity and enhanced dyeability. The research will cover the ionic crosslinking method to produce non-wrinkle durable-press effects for cotton. This will involve treating cotton with either an anionic material, then reacting with a polycation; or reacting with a cationic material, then applying a polyanion. They will make anionic cotton by reacting cellulose with chloroacetic acid (CAA) to attach negative anionic sites to the cellulosic fibers, and treat the anionic cellulose with a wide variety of positive cations to get improved WRA performance. They also will treat cellulosic fabric with 3-chloro-2-hydroxypropyl trimethyl ammonium chloride (CHTAC) to attach positive cationic sites to the fiber, and then treat the cloth with a wide variety of negative anions. Intellectual Merit: When treated with formaldehyde-based crosslinkers, cellulosic fabrics show improved mechanical stability, crease recovery angle (CRA) and durable press performance. But resin treatment also causes fabrics to lose strength, and later to release formaldehyde, a known human carcinogen. The PIs have discovered that ionic crosslinks can be used to stabilize cellulose using high molecular weight reactive ionic materials that do not release hazardous reactive chemicals, but at the same time provide outstanding CRA as well as complete strength retention in treated goods. The PIs plan to study the physical and chemical mechanism of this stabilization and to test a wide variety of ionic crosslinking agents and methods for producing these crosslinks in cellulosic textile materials. This requires: 1) basic research in the chemical laboratory, and 2) implementation of the best chemical principles in a commercial production setting. The results have the potential for positive environmental impacts.Broader impacts: To stabilize cotton textile products, which are widely used nearly everywhere, they are universally treated with resins that later release formaldehyde, a known human carcinogen. These resins also can cause strength loss and color change. A long-standing goal of textiles producers is to produce easy care, wrinkle-resistant cellulosic fabrics without the use of formaldehyde-based reactants. Also, the presence of ionic charges on cotton can allow much higher exhaustion of dyes of the opposite charge. This give a possible solution to the two greatest problems facing cotton dyers: (1) Excessive color waste and color pollution in the wastewater from textile dyeing operations, and (2) aquatic toxicity caused by massive amounts of salt that are currently used to dye cotton goods. The project provides an opportunity for the Egyptian scientists to expand a type of expertise that could serve their country well over time, and since Egypt is a cotton producer, this could lead to economic and technical advances in that country. The project will involve support for at least one post-doctoral student, and will also involve graduate students at NCSU. The PIs will interact with other academic investigators, as well as chemical manufacturers and textile manufacturers. This project is being supported under the US-Egypt Joint Fund Program, which provides grants to scientists and engineers in both countries to carry out these cooperative activities.