INFLUENCE OF ALKALINE PEROXIDE BLEACHING ON THE ELECTROKINETIC PROPERTIES OF ASPEN CTMP

摘要

CTMP from aspen was subjected to alkaline peroxide bleaching at various conditions, and the electrokinetic properties of resulted pulp were investigated. The correlation of increased charge groups with the swelling and strength properties of the pulp was also evaluated. The results indicated that carboxyl content, surface charge, dissolved charge, and zeta potential of BCTMP increased with increasing the dosages of sodium hydroxide and hydrogen peroxide, elevating the bleaching temperature and extending the bleaching time. Furthermore, the water retention value of BCTMP increased with increasing charge groups, indicating that the swelling ability of bleached fibres was improved. It was also found that alkaline peroxide bleaching could improve the strength properties but reduce light scattering coefficient of papers. Compared with control pulp, the length and width of alkaline peroxide bleached pulp fibres changed little, but their curl and kink index declined sharply.