Study of the changes in the structure and the water absorption properties by the pulp mixing ratio

Abstract

The effects of pulp types on the structure and the water absorption properties of pulp mold were investigated. The ONP (old newspaper recycled pulp), Sw-TMP (softwood thermomechanical pulp), Hw-BKP (hardwood bleached kraft pulp) were selected for this study. The pulp mold samples were prepared by using the laboratory wet pulp mold simulator. The pulp mold samples made with ONP showed lower bulkiness, lower Klemm water absorption property, lower maximum water contents and lower saturated water contents than those of the pulp mold made with Hw-BKP, which might be originated from the lower hydrophilicity and the higher ash contents of ONP. The addition of Sw-TMP increased the bulk and the water absorption properties of the pulp mold samples made with ONP. However, in case of the pulp mold samples made with Hw-BKP, the higher addition of Sw-TMP resulted in the lower Klemm water absorption and the lower saturated water contents. These results showed that the structural properties and the water absorption properties of pulp mold could be controlled by the raw materials depending on the fiber properties. ? 2018 Korean Technical Assoc. of the Pulp and Paper Industry. All rights reserved.