Solvent/10.00 Step 3 Water/43.20 Ammonium Caseinate* Sol'n. (10% solids)/- Resin/40.00 Oleic Acid/0.65 Solvent/10.00 Oleic Acid/0.25 Resin/40.00 Potassium Hydroxide Sol'n. (2.5%)/6.15 Potassium Hydroxide Sol'n. (2.5%)/6.15 Water/24.50 Ammonium Caseinate* Sol'n. (10% solids)/15.00 * When a long shelf is required, a preservative for the caseinate (such as "Dowicide" G" is added.
配制方法:
Step 1: Dissolve resin and oleic acid in solvent. For optimum particle size, the solution should have a viscosity of 25-35 poises. Since this range is very critical, with a particular combination of resin and solvent it may be necessary to adjust the resin or solvent proportions given in the table. Step 2: Slowly add the potassium hydroxide solution (2.5%) to the resin solution with stirring to obtain a homogeneous dispersion. This is a critical step, results depending on rate of addition of the alkali, degree of agitation, and temperature. Optimum cOnditions are determined through trial. Step 3: Next add ammonium caseinate (if used) and disperse thoroughly. Then add sufficient water to the emulsion, with continued agitation, to obtain a 40% solids emulsion. The resin emulsion is now ready for compounding with a latex to produce an emulsion adhesive. Several guide lines are useful in the preparation of the resin emulsions discussed above. The pH of resin emulsions should be mildly alk