Influence of Pulp and Wood Properties on the Unreacted Residuals in Carboxymethyl Cellulose

Sammanfattning: In this work, the influence of pulp and wood properties on the amount and properties of unreacted residuals in carboxymethyl cellulose was evaluated.

The results show that the presence of undissolved residuals in the CMC was not due to any chemical difference between these residuals and the reacted fibres. The undissolved residuals were also shown to consist mainly of swollen cell wall parts and some whole fibres, mainly thick-walled compression wood and latewood fibres.



Pulp with a viscosity of about 1500 dm3/kg produced undissolved residuals with a higher degree of substitution (DS) in their hemicelluloses than pulps with a viscosity of about 1350 dm3/kg. The undissolved residuals from the pulp with a higher viscosity also contained more swollen particles. It was therefore believed that a higher DS of the hemicelluloses in the CMC increased the potential for the fibre structure to swell.

It was also shown that the total DS of the CMC, the DS of the hemicelluloses in the CMC and also the DS of the residuals were related to the cellulose and galactoglucomannan contents of the original pulp. The amount of residuals seemed to be influenced mainly by the characteristics of the cellulose in the pulp