Thermal and Photochemical Crosslinking of Paper Fibers for Generation of Paper Substrates Providing a High Wet Strength and Multiple Chemical Fucntions

纸纤维的热交联和光化学交联生成具有高湿强度和多种化学功能的纸基材

• 批准号: 405422473
• 负责人: Professor Dr. Markus Biesalski
• 金额: --
• 依托单位: Fachgebiet Makromolekulare Chemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/405422473?language=en
• 关键词: Thermal; Photochemical; Crosslinking; Paper; Fibers

If paper comes into contact with water, the mechanical strength decreases considerably and under certain circumstances only reaches a few percent of the initial strength. For this reason, when producing papers that are intended for use in which they can get wet, significant amounts of a so-called wet strength agents - mostly cationic polymers - are added. These wet strength agents are attached to paper fibers, are partially chemically cross-linked and strengthen the paper fibers and their cohesion, although the details of this reinforcement mechanism have not been clarified down to the last detail. The commonly used wet strength agents are, however, not without problems in terms of their environmental behavior. In the current funding phase, it has been possible to use C,H insertion crosslinking processes (CHic process) to generate papers that have a wet strength that is 50 times better than that of unmodified paper. For this purpose, photochemical and thermally induced crosslinking processes have been developed or further developed. Furthermore, the first results to elucidate the reinforcement mechanism of the paper fibers could be obtained. The aim of the continuation of the research project is to further continue our investigations into wet-strength development of functionalized papers. The focus will be on studies that will further improve our understanding of the reinforcement mechanism in wet papers. For this purpose, the distribution of the polymers in the paper is to be analyzed in more detail and individual fiber experiments are to be continued. To investigate the polymer immobilization (CHic method), the topology of the cellulose fibers is to be stained with the help of specific binding enzymes that contain the carbohydrate binding motif. Furthermore, changes are to be made in the chemical structure of the wet strength agent, which allow rapid bonding and reinforcement of the paper even at temperatures below 100 ° C, so that the papers do not have to be completely dry for the wet-strength finish, which would result in considerable energy savings. In addition, the concept is to be expanded so that even paper fibers and incomplete papers can be modified and the concentration of polymers used can be significantly reduced. In addition, the concept is to be expanded so that paper fibers can already be modified before paper production and the use concentration of the polymers can be significantly reduced. Furthermore, first concepts for the design of multifunctional wet strength agents will be investigated, in which the improvement of wet strength is combined with further functionalities.

如果纸与水接触，机械强度会大大降低，在某些情况下仅达到初始强度的百分之几。出于这个原因，当生产旨在用于其中它们可以变湿的纸时，添加大量的所谓的湿强度剂-主要是阳离子聚合物。这些湿强度剂附着于纸纤维，部分化学交联并增强纸纤维及其内聚力，尽管这种增强机理的细节尚未被阐明到最后的细节。然而，常用的湿强剂在其环境行为方面并非没有问题。在目前的资助阶段，已经可以使用C，H插入交联工艺（CHic工艺）来产生湿强度比未改性纸好50倍的纸。为此，已经开发或进一步开发了光化学和热诱导交联方法。初步揭示了纸纤维的增强机理。该研究项目的目的是继续进一步研究功能化纸张的湿强度发展。重点将是研究，这将进一步提高我们的理解，在湿纸的增强机制。为此，将更详细地分析论文中聚合物的分布，并继续进行单独的纤维实验。为了研究聚合物固定化（CHic方法），纤维素纤维的拓扑结构将在含有碳水化合物结合基序的特异性结合酶的帮助下染色。此外，湿强剂的化学结构也将发生变化，即使在低于100 ° C的温度下也能快速粘合和增强纸张，因此纸张不必完全干燥即可进行湿强整理，这将节省大量能源。此外，这一概念还将得到扩展，甚至可以对纸纤维和不完整的纸张进行改性，并显著降低所用聚合物的浓度。此外，这一概念还将得到扩展，以便在造纸之前就可以对纸纤维进行改性，并且可以显著降低聚合物的使用浓度。此外，第一个概念的多功能湿强剂的设计将进行调查，其中湿强度的改善与进一步的功能相结合。