Establishment of Stabilization Technology of Extruded Starch Fibers

A.将约10%的淀粉水溶液加入40%的硫酸铵溶液中，在60℃下通过直径为0.2mm的圆形或矩形加压喷嘴挤出，可制得淀粉纤维。在各种淀粉样品中，玉米淀粉最适合制备淀粉纤维，这可能是由于玉米淀粉中直链淀粉和支链淀粉的质量比合适。为了提高所得淀粉纤维在热或弱碱性条件下纤维形态的稳定性，对淀粉纤维进行了交联处理。然而，只要到目前为止所考察的各种条件，就不能获得足够的形状稳定性。另一方面，当碳酸钙或氧化钛填料混合在淀粉溶液中用于挤出时，所获得的淀粉纤维具有较高的形状稳定性，以热和弱碱性条件。此外，通过使用这些含有无机填料的淀粉纤维，可以保持手抄纸的不透明度。以黄原酸盐溶液作为两种多糖的共溶剂，通过纺丝制备纤维素-淀粉杂化纤维。由于纤维素组分主要存在于这些混杂纤维的表面，因此在混杂纤维上不会出现由于淀粉组分而产生的特定性质。因此，控制淀粉和纤维素组分在混杂纤维横截面中的分布是必要的，以改善纤维素-淀粉混杂纤维的未来工作。

A. Starch fibers can be prepared by extruding about l0% aqueous starch solutions into 40% ammonium sulfate solutions at 60℃ through a pressurized nozzle with circle or rectangular shape of 0.2 mm diameter. Among various starch samples, corn starch was the best for preparing starch fibers probably because of a suitable weight ratio between amylose and amylopectin in the corn starch.B. In order to increase stability of fibrous shape of the obtained starch fibers to thermal or weakly alkaline conditions, some kinds of cross-linking reagents were applied to the starch fibers. However, sufficient shape-stability could not be achieved as long as the various conditions examined so far.C. On the other hand, when calcium carbonate or titanium oxide filler was mixed in the starch solutions for extruding, the obtained starch fibers had higher shape-stability to thermal and weakly alkaline conditions. Furthermore, opacity of handsheets can be maintained by using these starch fibers containing the inorganic fillers.D. Cellulose-starch hybrid fibers were prepared by spinning their xanthate solutions as a co-solvent for the two polysaccharides. Because the cellulose component is predominantly present at the surfaces of these hybrid fibers, specific properties due to the starch component do not appear on the hybrid fibers. Thus, controlling distributions of starch and cellulose components in the cross-sections of hybrid fibers are necessary to improve the cellulose-starch hybrid fibers for future work.