Processing Lyotropic Crystalline Solutions of Cellulose in the Liquid Ammonia/Ammonium Thiocyanate Solvent System to Form High Performance Fibers and Films

纤维素具有形成纤维和薄膜的潜力， 比目前已知的更强。 提出要 通过液晶溶液的湿法纺丝来实现这一点， 在氨/硫氰酸铵溶剂体系中形成。 的倾向 使手性纤维素分子形成手性溶液， 得到补偿，并形成替代解决方案， 调节溶剂比和聚合物浓度。 研究 到目前为止表明，一个系统是首选的，从 将形成高强度、高模量的纤维。 在 开发生产这种纤维的方法，必须仔细注意 给出了重要的纺丝参数和后挤出 条件 纤维素是一种天然存在的材料， 工业上用作从树木中提取的木浆或从棉花中提取的纤维。 两种形式的纤维素都不熔化，也不容易溶解在水中。 任何溶剂。 为了制造有用的产品，例如纤维或 从纤维素薄膜，一个人必须能够通过处理熔融成型 或解决方案。 此外，已经发现，如果非常 在溶剂中产生浓缩溶液，这是一种非常有趣的方法。 一种叫做液晶的物质形式就可能产生。 如果纤维或薄膜 是由这些纤维素液晶，新纤维， 织物和薄膜，它们非常坚固， 抵抗 新的轻质、坚固、坚硬的 材料或复合材料可以取代钢和其他传统材料。 工程材料在许多方面的应用。

Cellulose has the potential for forming fibers and films that are much stronger than those which are currently known. It is proposed to accomplish this via wet spinning of liquid crystalline solutions that form in an ammonia/ammonium thiocyanate solvent system. The tendency for the chiral cellulose molecules to form cholesteric solutions can be compensated and nematic solutions formed in their stead by adjusting the solvent ratio and the polymer concentration. Research thus far indicates that a nematic system is the preferred one from which high strength, high modulus fibers will be formed. In developing a process for producing such fibers, careful attention must be given to both important spinning parameters and to post extrusion conditions. Cellulose is a naturally occurring material which is available to industry as wood pulp from trees or as fibers from cotton plants. Cellulose in either form does not melt nor does it dissolve readily in any solvent. In order to make a useful product, such as a fiber or a film from cellulose, one must be able to shape it by processing a melt or a solution. Further, it has been discovered that if very concentrated solutions are produced in a solvent, a very interesting form of matter called liquid crystals may develop. If fibers or films are prepared from these cellulose liquid crystals, new fibers, fabrics, and films may be formed which are exceptionally strong and resistant. It is possible that the new lightweight, strong, stiff materials or composites could replace steel and other conventional engineering materials in many uses.