丙酸酯变性淀粉浆料的研究

Study on the Properties of Propionylated Starch Used as Warp Sizing Agents

采用丙酸酐作为酯化剂,通过改变丙酸酐对玉米淀粉的投料比,制备一系列具有不同取代度(DS)的丙酸酯淀粉,以研究淀粉丙酸酯化变性程度与浆液黏附性能和浆膜性能的关系,并通过与醋酸酯化变性的对比,来评价淀粉丙酸酯化淀粉的上浆性能.实验结果表明:淀粉丙酸酯化变性能够显著改善淀粉对涤纶纤维的黏附性能,提高淀粉浆膜的断裂伸长率和耐屈曲次数,降低浆膜的磨耗;随着取代度的增加,丙酸酯淀粉对涤纶纤维的黏附力先增大后减小,当取代度为0.019时,黏附力达到最大;相近取代度下,丙酸酯淀粉的浆膜性能及对涤纶纤维的黏附性能均优于醋酸酯淀粉.作为浆料使用的丙酸酯淀粉,其变性程度不宜过大.

In order to reveal the inherent relation between the sizing properties and modification extent,a series of propionylated starch with different degree of substitution（DS）were prepared using propionic anhydride as esterifying agent through varying the feed ratio of the agent to starch.The sizing properties of propionylated starch were also evaluated by contrasting with acetylated starch.The experimental results demonstrated that the propionylation enhanced the adhesion of starch to polyester fibers,and improved the breaking elongation,flex resistance and wear loss of starch film.As the DS value increased,the adhesion of propionylated starch to polyester fibers initially increased,reached a maximal value at 0.019 and then decreased.Furthermore,propionylated starch was superior to acetylated one in the behaviors of starch film and the adhesion-to-polyester fibers when the DS was similar.The modification extent of the propionylated starch used as warp sizing agents should not be extremely too high.