Mechanical pulps are widely used in the production of newsprint, and resin is the main component of wood extractives in the pulp, which is harmful to both the wet-end and paper quality especially in newsprint paper mi...Mechanical pulps are widely used in the production of newsprint, and resin is the main component of wood extractives in the pulp, which is harmful to both the wet-end and paper quality especially in newsprint paper mill. In the case of mill whitewater closure, the problems become more noticeable. In this work, the CRC (colloid resin component) simulacrum was made by individually dispersing the oleic acid and glyceride with mechanical method, and the effects on wet-end chemical characteristics and newsprint physical proprieties were discussed. It was found that some of the wet-end characteristics such as cationic demand, Zeta potential, and first pass retention were remarkably affected by the CRC simulacrum. The first pass retention decreased from 75.7% to 69.2% in the presence of oleic glyceride and from 81.7% to 78.4% in the presence of oleic acid in PEO/PFR retention system and from 78.6% to 75.4% (with oleic glyceride) and 74.3%to 70.1%(with oleic acid) in PEI/CPAM retention system. The CRC simulacrum of oleic acid and glyceride remarkably decrease the tensile strength and tear strength of newsprint hand sheets. The scattering coefficient of the hand sheets increased with the concentration of simulacrum.展开更多
文摘Mechanical pulps are widely used in the production of newsprint, and resin is the main component of wood extractives in the pulp, which is harmful to both the wet-end and paper quality especially in newsprint paper mill. In the case of mill whitewater closure, the problems become more noticeable. In this work, the CRC (colloid resin component) simulacrum was made by individually dispersing the oleic acid and glyceride with mechanical method, and the effects on wet-end chemical characteristics and newsprint physical proprieties were discussed. It was found that some of the wet-end characteristics such as cationic demand, Zeta potential, and first pass retention were remarkably affected by the CRC simulacrum. The first pass retention decreased from 75.7% to 69.2% in the presence of oleic glyceride and from 81.7% to 78.4% in the presence of oleic acid in PEO/PFR retention system and from 78.6% to 75.4% (with oleic glyceride) and 74.3%to 70.1%(with oleic acid) in PEI/CPAM retention system. The CRC simulacrum of oleic acid and glyceride remarkably decrease the tensile strength and tear strength of newsprint hand sheets. The scattering coefficient of the hand sheets increased with the concentration of simulacrum.
