The solubility of cellulose in liquid ammonia/ammonium thiocyanate solution: The effect of composition and temperature on dissolution and solution properties

The dissolution process and some solution properties of cellulose in mixtures of liquid ammonia (NH₃) and ammonium thiocyanate (NH₄SCN) are discussed. The mole fraction ratio of NH₃, NH₄SCN, and H₂O which dissolve cellulose were determined. The effect of temperature on several solution properties was also examined. The temperature coefficient d In n]/dT for the limiting viscosity number n] has a value of ?1.58 × 10^?2 °C^?1. This is considered to be rather large but is, in fact, a common occurrence for almost all cellulose derivatives in solution. The values for the Huggins constant K′ showed no systematic trends with temperature. They did, however, suggest the presence of considerable association of the cellulose in solution. Miscibility results of adding the cellulose solutions to organic liquids are also reported.