Abstract:AKD and PCC were pre-flocculated with dual-component retention system: CPAM and bentonite. The effects of addition sequence of each constituent on sizing, filler retention and physical properties of paper were investigated. Compared with the traditional filling process, it was found that when the pre-flocculation process of [PCC+CPAM+bentonite+CS+AKD] was used, the mechanical properties of paper were obviously improved, the tensile index and the burst index were increased by 22.4% and 52.0%, respectively. Meanwhile, the formation index was significantly decearsed from 111.9 to 69.0. When AKD was added to the pulp before filling by using pre-flocculation process of [PCC+CS+CPAM+bentonite], the sizing degree and the filler retention rate of the paper were significantly improved, the Cobb60 value reduced by 24.8%,while the filler retention rate increased by 3.7% compared with the traditional filling process. However, all pre-flocculation processes could reduce whiteness, opacity and air permeability of the paper due to the increase of particle size of PCC. |