Solutions of cellulose and its blends with synthetic polymers in N-methylmorpholine-N-oxide: Preparation, phase state, structure, and properties

Highly concentrated solutions of cellulose and solutions of cellulose blends with synthetic polymers are prepared via the solid-phase dissolution of cellulose in N-methylmorpholine-N-oxide. The phase state and morphological features of these solutions are studied via DSC and polarization microscopy, and their rheological behavior is considered. Evolution in the structure of cellulose in these systems is investigated at all stages during spinning of oriented fibers from solutions. It is first shown that the addition of synthetic polymers to cellulose makes it possible to control processes of cellulose structuring; to stop them at the stage of mesophase formation; and, thus, to avoid further perfection of the structure and formation of the crystalline phase of cellulose.