马来酸酐酯化变性对淀粉浆料的影响

 摘要：采用不同投料比，制备一系列具有不同取代度的马来酸酐酯变性淀粉，测试其浆液黏度、浆膜及黏附性，以明确马来酸酐酯化变性对淀粉浆料性能的影响。通过与酸解淀粉及醋酸酯淀粉的比较，评价了马来酸酐酯化淀粉的上浆性能。结果表明：马来酸酯化变性能够有效增加淀粉浆膜的断裂伸长和断裂功，提高对涤纶及棉纤维的黏附性，改善退浆性。当变性程度相近时，马来酸酐酯化淀粉浆料的性能优于醋酸酯淀粉。从黏附力、浆膜性能、反应效率等方面判断，马来酸酐酯化淀粉的取代度以0.036为宜；制备方法是：首先应采用适当的方式对淀粉原料降黏，然后将淀粉质量25%的马来酸酐缓慢加入到淀粉水分散液中，控制反应体系的pH7.5～8.5，最后在30℃下搅拌反应1h。

Effect of esterifying modification of maleic anhydride on its sizing properties

Abstract In order to reveal the impact of maleic anhydride-esterification of starch on the properties of starch sizes, a series of maleic anhydrided starch (MAS) with different degree of substitution (DS) were prepared by reacting differeny amount of anhydride with starch. Viscosity of cooked starch pastes, starch film, and adhesion to polyester and cotton fibers were examined. The properties were assessed through the comparison of MAS with acid-thinned starch (ATS) and acetylated starches (AS). The results showed that the maleic anhydride-esterification were able to increase the work to break, tensile strength of starch film and improve desizing performance, and enhance the adhesion of starch to polyester fibers. The MAS was superior to ATS and AS in improving the properties of starch film and the adhesion to polyester fibers under similar DS level. Applicable DS of MAS for sizing polyester warp was 0.036. The MAS could be obtained through adding 25% maleic anhydride into an aqueous dispersion of starch and then reacting the system for I h under pH 7.5-8.5 and 30℃ after an acid-thinning for reducing the viscosity of cooked starch paste.