Abstract:

With Chinas goal of peaking carbon emissions before 2030 and achieving carbon neutrality before 2060, the development of low carbon starch has become an important research and development direction of low carbon textile starch weaving. Starch has been widely developed and applied in the field of low carbon textile starch because of its rich source, renewablity, modification, biodegradability and other properties. However, the strong network structure of hydrogen bonds within and between molecules of starch leads to hard and brittle film forming, which is difficult to meet the requirements of sizing weaving. In order to overcome the defect of starch membrane formation, researchers modified the starch structure to weaken the intramolecular and intermolecular hydrogen bond network structure through various methods such as esterification, etherification, grafting and plasticizer, and introduced new substituents to further destroy the hydrogen bond interaction in the starch structure. Acetate starch, with its advantages of low gelatinization temperature and high viscosity thermal stability, provides potential for low temperature and low carbon sizing. However, acetate starch still has the problem of brittle film forming. The plasticizing mechanism of acetate starch and the correlation between plasticizer and plastic acetate starch yarn have not been reported publicly.

In this paper, acetate starch was prepared by acetylation of starch with acetic anhydride as the modifier, and plastic acetate starch size was obtained by plasticizing with diammonium hydrogen citrate. The chemical structure of acetate starch was analyzed, the size film mechanical properties and plasticizing mechanism of plastic acetate starch were studied, the viscosity and thermal stability of plastic acetate starch size were tested, and the plastic acetate starch size was applied to the sizing practice of superfine cotton yarns. The FT IR results showed that the ester group characteristic peaks appeared on the structure of acetate starch. Compared with acetate starch, the plastic acetate starch size film presents a higher elongation at break, which is due to the fact that the formation of hydrogen bond between diammonium hydrogen citrate and the hydroxyl group on the structure of acetate starch weakens the hydrogen bond network structure of the starch itself and improves the compliance of the molecular chain. When diammonium hydrogen citrate is 1% of starch acetate, the size film shows better toughness and mechanical properties. In addition, the plastic acetate starch size shows high viscosity thermal stability, and has good sizing effect on superfine cotton yarns.

Studying the plasticizing mechanism of plastic acetate starch and the properties of its size film, serous fluid and sizing can effectively solve the inherent brittle and hard defects of starch forming, provide a theoretical basis for exploring the mechanism of starch forming and plasticizing, provide technical support for the development of low carbon high performance textile starch slurry, and promote the development of low carbon textile sizing weaving.

Key words: diammonium hydrogen citrate, plastic acetate starch size, film property, sizing property

摘要： 以醋酸酐为改性剂对淀粉乙酰化处理制备了醋酸酯淀粉，进一步通过柠檬酸氢二铵对其增塑得到了塑性醋酸酯淀粉浆料。分析了醋酸酯淀粉的化学结构，研究了塑性醋酸酯淀粉浆料的浆膜力学性能和增塑机制，测试了塑性醋酸酯淀粉浆液黏度和热稳定性，并将其用于纯棉特细纱上浆工艺实践。红外测试表明醋酸酯淀粉结构上有酯基特征峰；与醋酸酯淀粉相比，塑性醋酸酯淀粉浆膜呈现高的断裂伸长率，这是由于柠檬酸氢二铵与醋酸酯淀粉结构上的羟基所形成的氢键作用，削弱了淀粉自身氢键网状结构，使分子链柔顺性提高。塑性醋酸酯淀粉浆液表现出高的黏度热稳定性，对纯棉特细纱浆纱效果良好。

关键词: 柠檬酸氢二铵, 塑性醋酸酯淀粉, 浆膜性能, 浆纱性能