抄録
The sulfidation-resistance value (S-W), proposed by Bartunek as a measure of reactivity of dissolving pulp, is the amounts of undissolved residue of pulp after emulsion xanthation at the definite concentration of sodium hydroxide solution, sufficient to mercerize cellulose, with 25% of carbon disulfide based on the pulp. So the Bartunek's S-W shows only a point on the emulsion xanthation solubility curve (S-W curve) as a function of the amounts of carbon disulfide added. In the previous paper, the significance of S-W curve as a measure of reactivity or filterbility of viscose from the pulp was studied.
In this paper, the relation between S-W curve and Bartunek's S-W is studied in order to research the significance of Bartunek's S-W as a measure of reactivity of dissolving pulp. The results are as follows:
Bartunek's S-W correlates not only to the amounts of carbon disulfide required for dissolving 50% of pulp, but also A1, A2 and A3. Here, A1 and A2 are the average “dissolved-distances” per unit amount of carbon disulfide on the first and second inflexion points of calculated S-W curves respectively, and A3 is the average amount of the dissolved per unit amount of carbon disulfide during the reaction (see Fig. 5). However Bartunek's S-W has no correlation to the characteristics of S-W curve, obtained in the previous paper as to the state of viscose solution.
From the above, the following conclusion may be drawn. Bartunek's S-W gives only an average measure of solubility in emulsion xanthation, and has no definite significance as a measure of reactivity of dissolving pulp or a measure of filterbility of viscose prepared from the pulp.
