High-Quality Cellulosic Fibers Engineered from Cotton-Elastane Textile Waste.

Even small amounts of elastane in cotton-elastane blended textiles can prevent fiber-to-fiber recycling strategies in textile recycling. Herein, the selective separation of elastane from cotton blends was addressed by the aminolytic degradation of the synthetic component. Polar aprotic solvents were tested as elastane solvents, but side reactions impeded aminolysis with some of them.

Rapid in situ quantification of rheo-optic evolution for cellulose spinning in ionic solvents.

It is critical to monitor the structural evolution of complex fluids for optimal manufacturing performance, including textile spinning. However, in situ measurements in a textile-spinning process suffer from the paucity of non-destructive instruments and interpretations of the measured data. In this work, kinetic and rheo-optic properties of a cellulose/ionic liquid solution are measured simultaneously while fibers are regenerated in aqueous media from a model wet-spinning process via a customized polarized microscope.

Understanding the Dynamics of Cellulose Dissolved in an Ionic Liquid Solvent Under Shear and Extensional Flows.

Ionic liquids (ILs) hold great potential as solvents to dissolve, recycle, and regenerate cellulosic fabrics, but the dissolved cellulose material system requires greater study in conditions relevant to fiber spinning processes, especially characterization of nonlinear shear and extensional flows. To address this gap, we aimed to disentangle the effects of the temperature, cellulose concentration, and degree of polymerization (DOP) on the shear and extensional flows of cellulose dissolved in an IL. We have studied the behavior of cellulose from two sources, fabric and filter paper, dissolved in 1-ethyl-3-methylimidazolium acetate ([CCIm][OAc]) over a range of temperatures (25 to 80 °C) and concentrations (up to 4%) that cover both semidilute and entangled regimes.

Kinetic analysis of microwave-enhanced cellulose dissolution in ionic solvents.

Cellulose dissolution in mixtures of the ionic liquid 1-ethyl-3-methylimidazolium acetate with dimethylsulfoxide, [CCIm][OAc] + DMSO, have been kinetically compared using conventional heating and microwave heating in a single-mode cavity with a semiconductor generator. Microwaves led to enhancements in the dissolution rate between 21 and 57% under different conditions of temperature and concentration of ionic liquid. Rate enhancement by microwaves prominently occurred at temperatures above 60 °C.

Strong Microheterogeneity in Novel Deep Eutectic Solvents.

With the increasing application of template assisted syntheses in deep eutectic solvents and successful application of hydrophobic deep eutectic solvents in extraction processes, where microheterogeneity plays a major role, suggestions for novel deep eutectic solvents which exhibit strong microheterogeneity are desirable. Therefore, classical molecular dynamics simulations were carried out on deep eutectic solvent systems constructed of choline chloride and some of its derivatives mixed with ethylene glycol in a molar composition of 1 : 2 since this is the optimal parent composition. The derivatives consisted of a series of elongated alkyl side chains and elongated alcohol side chains.