微波辅助羧甲基玉米淀粉的制备及其上浆性能

为获得对纯棉高支纱线具有优良上浆效果的浆料，以玉米淀粉为原料，一氯乙酸为醚化剂，氢氧化钠为催化剂，微波辅助制备了一种亲水改性淀粉浆料羧甲基玉米淀粉(CMCS)。借助红外光谱仪和扫描电子显微镜对产物的分子结构和颗粒形态进行分析，并对其理化特性及对纯棉纤维的黏附性进行研究。结果表明：玉米淀粉大分子上成功引入了羧甲基取代基团， CMCS 颗粒出现不同程度破损，完整性遭到破坏；CMCS 的特性黏数和表观黏度降低，流动性增强，其溶解性、膨胀性和糊透明度提高，抗凝沉性增强，蓝值下降，直链淀粉发生降解；CMCS 的糊化温度下降，糊化性能和糊加工性能得到改善；CMCS 黏附性能相比于原淀粉最高可增加27. 9%，并且随着取代度的提高，黏附性逐渐增强。对9. 67 tex 纯棉纱上浆实验结果表明，CMCS 浆纱的力学性能显著提高，其浆纱的断裂增强率与耐磨增强率分别比原淀粉浆纱增加了118. 5%和88. 7%，伸长率降低了29. 7%。

Microwave assisted preparation and sizing properties of carboxymethyl corn starch

In order to obtain an excellent sizing effect for cotton high-count yarn, a hydrophilic modified starch size-carboxymethyl corn starch (CMCS) was synthesized from natural corn starch, chloroacetic acid and sodium hydroxide as raw material, etherifying reagent and catalyst by a microwave-assisted process. The molecular structure and granular morphology of the products were characterized by FT-IR and SEM. The results show that carboxymethyl groups are successfully introduced into corn starch macromolecule and starch granules are damaged by varying levels and their integrity is destroyed. The studies for physicochemical properties of CMCS show that the intrinsic viscosity and apparent viscosity of CMCS decrease, rheological property is enhanced, the solubility, swelling power, paste clarity and retrogradation resistance are improved, the blue value reduces, suggesting the degradation of amylase. The gelatinization temperature decreases, which indicates that gelatinization properties and paste processing performance are improved. The results of the adhesion experiment show that the adhesion force of CMCS is enhanced by as much as 27. 9% compared with nature corn starch(NCS), and the adhesion force increases with the increase of degree of substitution. The results of sizing experiments on 9. 67 tex pure cotton yarns show that the mechanical properties of CMCS sized yarns are significantly improved, the tensile strength enhancement and abrasion resistance enhancement increase by 118. 5% and 88. 7%, respectively, and the elongation reduction is 29. 7% lower than that of NCS sized yarns.