Étude, par spectroscopie de vibration, de deux solvants de la cellulose: La N-méthyl morpholine N-oxyde et son monohydrate

Abstract

The ir and Raman spectra of N-methyl morpholine N-oxide and its monohydrate have been investigated in the frequency range 4000–50 cm−1. For these two compounds, classified among the best cellulose solvents, there exists only the conformer where NO and CH3 groups are respectively in axial and equatorial positions. For anhydrous N-methyl morpholine N-oxide, the dipole–dipole interaction is characterized by a strong line at 75 cm−1 in the Raman spectra.The molecules can be divided into two parts: a hydrophobic part (O(CH2)2) not active in the cellulose dissolution, and a hydrophilic part, which is able to stabilize a chain of water molecules and reveals the importance of the pyramidal environment of water molecules in the monohydrate.