N-Methylmorpholine N-oxide

About: N-Methylmorpholine N-oxide is a research topic. Over the lifetime, 187 publications have been published within this topic receiving 5251 citations. The topic is also known as: N-Methylmorpholine oxide & N-Methylmorpholine 4-oxide.

Oriented cellulose films and fibers from a mesophase system

Abstract: Cellulose mesophases were obtained by preparing concentrated solutions of cellulose (20–55%) in a mixture of N-methyl-morpholine N-oxide (MMNO) and water. The anisotropy depends on four interconnected parameters: the temperature of the solution which, in general, must be lower than 90°C; the concentration of cellulose which must exceed 20%; a water content such that the mole ratio water/anhydrous MMNO is smaller than unity; and the degree of polymerization of the dissolved cellulose. The anisotropic cellulose solutions can readily be oriented during extrusion or casting thus giving fibers or films which upon regeneration exhibit high orientation.

Swelling and Dissolution of Cellulose Part 1: Free Floating Cotton and Wood Fibres in N‐Methylmorpholine‐N‐oxide–Water Mixtures

Abstract: Five modes describing the behaviour of cellulose fibres dipped in a chemical have been identified: Mode 1: Fast dissolution by disintegration into rod-like fragments Mode 2: Large swelling by ballooning, and then dissolution of the whole fibre Mode 3: Large swelling by ballooning, and partial dissolution of the fibre, still keeping its fibre shape Mode 4: Homogeneous swelling, and no dissolution of any part of the fibre Mode 5: No swelling and no dissolution (case of a non-solvent) In the case of the behaviour of wood and cotton cellulose fibres in N-methylmorpholine-N-oxide (NMMO) and water mixtures, four domains of water content have been identified. Below 17% of water up to monohydrate (13%), the fibres are disintegrated into rod-like fragments and dissolve (mode 1). In NMMO - water mixtures containing 19-24% water, the cellulose fibres exhibit a heterogeneous swelling by forming balloons (composed of dissolved cellulose holds inside a membrane) separated with non-swollen sections. The whole fibre will completely dissolve (mode 2) in four successive steps (growth of the balloons, burst of the balloons, dissolution of the non-swollen sections and finally dissolution of the membrane). With still greater water contents (25-30%), only the ballooning phenomenon is observed, with a partial dissolution inside the balloon (mode 3). Above 35% of water, the fibres swell homogeneously and are not dissolving (mode 4).

Cellulose nanofibers prepared by the N-methylmorpholine-N-oxide method

Abstract: The process of electrospinning is very suitable for obtaining fibers with a diameter on a nanometer scale. Such fibers can be spun from almost all kinds of known polymers, copolymers, and polymer blends. In this work, we present cellulose nanofibers obtained by the electrospinning process from spinning dopes containing cellulose dissolved in an N-methylmorpholine-N-oxide/water system. Under different electrospinning process conditions, cellulose fibers, a nonwoven fiber network, and a cellulose membrane were obtained. The fibers were examined with scanning electron microscopy. The diameters of the fibers were in the submicrometer range. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1855–1859, 2005