HOECHST CELANESE IMPROVES CONSISTENCY OF CELLULOSE-ACETATE THROUGH AUTOMATED VISCOSITY MEASUREMENT

Hoechst Celanese has improved the precision of viscosity measurements from +/-6 to +/-2 centipoise by switching from manual to automated tes ting. Solution viscosity is one of the most critical quality parameter s in the production of cellulose acetate flake. In the past, the compa ny used a modified Cannon-Fenske tube for viscosity measurements. Oper ator influences, including time measurements, start and end points, ba th temperature, and other factors, made it impossible to achieve optim al accuracy. Switching to automated differential viscometers eliminate d operator influences from the measurement process thus enabling far m ore precise process control.