Cellulose is a natural polymer which is found in trees and plants and is commonly used for making milk and juice cartons. The problem with cellulose is that it does not melt and dissolve in the common solvents. The objective of this experiment is to characterize five different types of cellulose by comparing their molecular weight and degree of polymerization to each other, and dissolve cellulose at room temperature using potassium thiocyanate/ethylenediamine system. Each cellulose sample was ground up, dried in a vacuum oven over night and measured on an analytical balance. Cuen (copper-ethylenediamine complex) solution, water, and shaker bath were used to dissolve the samples. An Ubbelohde viscometer, a constant temperature bath (held at 25 °C) and a stop watch were used to determine the flow times of each solution. Intrinsic viscosity was calculated using a series of equations that included relative, specific, reduced, and inherent viscosities. Intrinsic viscosity was found by plotting reduced and inherent viscosity vs cellulose concentration and extrapolating reduced and inherent viscosity back to the zero concentration. These two viscosities should meet at the same point. Reduced and Inherent viscosities were compared to Martin equation to find the intrinsic viscosity. A 50 ml glass reactor equipped with a mechanical stirrer was used for dissolution of Waco DP 210 cellulose and Tycell. Ehylenediamine and potassium thiocyanate were added in first to create the solvent, and then DP 210 sample was added. It took about 48 hours for the complete cellulose dissolution.. Tyee cellulose had the highest molecular weight and DP out of the five cellulose types. The intrinsic viscosity that was determined from the reduced viscosity measurements appeared to be significantly different than that one obtained from the inherent viscosity and the Martin equation.
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