A New Solvent for the Industrial Production of Cellulose Fibers: Quaternary Ammonium Acetate

Abstract

Tetrabutylammonium acetate, a new solvent, can dissolve cellulose (8 wt%) within 5 min at 40°C with dimethyl sulfoxide as coslovent without any pretreatment or inert gas atmosphere. The dissolution detail was recorded by Confocal Laser Scanning Microscope. And the viscosity of cellulose solution prepared from the new solvent was only 10% of that prepared from [BMIM]Cl. Moreover, the influence of molecular weight on the rheology of the cellulose solution was investigated. With the increase of the molecular weight, the viscosity was increasing and the cross-over point of the storage modulus (G′) and loss modulus (G′′) curves shifted to the lower angular frequency. The structure and mechanical properties of the fibers prepared from the cellulose solution were characterized by FT-IR, XRD, SEM and DSC. During the dissolution process, the crystalline region of the cellulose was destroyed and the celluloseIbecame amorphous. However, part of amorphous cellulose transformed into celluloseII by the wet spinning, indicated by FT-IR and XRD spectrum. SEM images showed that the resulting fibers were homogeneous with smooth surfaces and circular cross-sections. Meanwhile, the cellulose fibers had good thermal stability, measured by DSC. This work provided a promising way to prepare cellulose fibers with good physical properties, which was green, low cost and suitable for industrial production.