和紙抄造工程に及ぼすトロロアオイ粘質物とポリエチレンオキサイドの効果の違いについて

Abstract

In connection with the paper making properties of tororo-aoi mucin (TM) and polyethylene oxide (PEO) solutions, the permeabilities of the polymer solutions through the rayon pulp bed and the sedimentation velocities of the pulp in the solutions were measured.The permeability of TM solution was significantly smaller than that of PEO solution under the same conditions, and increased rapidly by aging or by the addition of NaCl. The fluent flow of TM solution through the pulp bed was proved to be un-explainable by Darcy's equation.Close correlation was also confirmed among the viscosity and permeability of TM solution or the sedimentation velocity of rayon pulp in the solution and the initial conformational transition of an ordered, weak structure of TM molecule. It was further clarified that the paper making properties described above are remarkably influenced by the dissociation of carboxyl group present in TM molecule and by the surface state of pulp fiber.From the results, the characteristic paper making property of TM is appreciably explained to be occured by a pore radius decrease in the rayon pulp bed, which is due to the thicker immobile layer caused by TM adsorption on the fiber surface, and by the dissociation of carboxyl group present in the mucin molecule. It was also found that a decrease in the effect of TM on paper making is partially inhibited by the addition of PEO in the aqueous solution.