废旧棉/涤混纺织物的组分快速分离及其含量测定

基于高效溶解纤维素的低黏度离子液体/共溶剂体系,提出了一种废旧棉/涤(PET)混纺织物的组分分离与含量测定方法。考察了离子液体与共溶剂的种类及比例对废旧棉/涤混纺织物各组分的溶解能力、溶液黏度及分离过程对回收组分结构与性能的影响规律。结果表明:1-丁基-3-甲基咪唑醋酸盐/二甲基亚砜(质量比为1:1)共溶剂体系可选择性高效溶解棉/涤混纺织物中的纤维素成分,所得纤维素溶液黏度较低,经简单过滤即可实现棉/涤混纺织物中纤维素和PET的高效分离,该溶解分离过程在25~60 ℃即可实现,纤维素组分几乎不降解,可进一步加工成膜、纤维及凝胶微球等材料,未经预粉碎的废旧织物分离后回收的PET纤维形态完整,纯度高。该方法不仅能实现棉/涤混纺织物的组分分离,而且能准确测定棉(纤维素)和涤(PET)组成含量,有助于废旧纺织物的高效回收与再利用,具有重要的应用前景。

Rapid separation and content determination of fibers from waste cotton/polyester blended fabrics

Based on ionic liquid/co-solvent system with excellent dissolving capability for cellulose and relatively low viscosity, a method for rapid component separation and content determination for waste cotton/polyester blended fabrics was proposed. The effect of ionic liquid and co-solvent on the dissolving capability, solution viscosity, structure and properties of separated components was studied. The results indicate that the 1-butyl-3-methylimidazolium acetate/dimethyl sulfoxide (the mass ratio is 1:1) system can selectively dissolve cellulose in the cotton/polyester blended fabrics, and the resultant cellulose solution has a low viscosity. Subsequently, after a simple filtration, cellulose and polyester fibers can be completely separated under simple and mild conditions, with the separation temperature to be 25-60 ℃. The cellulose component is almost non-degradable, and can be processed into film, fibers and microspheres. The polyester component with a high purity can also be separated and keep its original textile morphology in blended fabrics. In summary, the ionic liquid/co-solvent method not only can high-efficiently separate the components of the cotton/polyester blended fabrics, but also can accurately measure the components content. Therefore, this work provides a promising and useful method to the recycling and re-utilization of waste textiles, indicating a great potential in the practical applications.