NOVEL DUAL-POLYMER RETENTION AIDS FOR NEWSPRINT AND GROUNDWOOD SPECIALTIES.
Abstract
In the reported experiments, fifteen polymeric materials, each in combination with high-molecular-weight poly(oxyethylene) (PEO), were evaluated for use as retention aids in furnishes containing groundwood pulps. Cartafen RL, a synthetic, water-soluble polymer, and three commercial products derived from kraft lignin were found to be effective. PEO plus Reax 85A, a modified kraft lignin, increased retention in newsprint and groundwood specialty stocks. In washed newsprint, retention with PEO plus Cartafen RL was independent of pH from 4 to 10 and was improved by alum addition. The effectiveness of a sulfonated kraft lignin was independent of alum concentrations and decreased when the pH was raised from 4 to 8.