The Effect of Cationized CMP Fines on Newsprint Pulp Properties

In this research، the effect of cationized CMP fines on newsprint pulp properties was investigated. The fines were first separated using a Dynamic Drainage Jar (DDJ) apparatus and then the cationic groups were established and firmly fixed on fines by chemical reactions and grafting with copolymerization mechanism so that the surface electrical charge of fines was changed to cationic. The cationized CMP fines were added alone and also together with polymeric retention aid، the cationic poly acryl amid، in newsprint furnish at three levels of consumption (low، medium and high) and the pulp properties including drainability (freeness)، first pass retention and also zeta potential and filtrate cationic demand variations were measured and compared with the control sample (pulp with only cationic poly acryl amid which is the main retention aid polymer in Mazandran Wood and Paper Industries Company). The results showed that although the cat ionized CMP fines by themselves could not have good effects on newsprint pulp quality، by cooperation with cationic poly acryl amid، the pulp quality and also retention aid polymer efficiency were increased. Indeed، the cationized CMP fines have a synergic effect on retention aid polymer efficiency. Therefore، the use of cationized CMP fines with cationic poly acryl amid can be recommended for increasing pulp drainability and first pass retention.