Effect of Different Contents of OCC Pulp Mixing on NSSC Pulp Strength

This research was conducted to study the effect of mixing different contents of old corrugated container (OCC) pulp on mechanical properties of virgin neutral sulfite semi chemical (NSSC) pulp. The NSSC pulp was procured from Mazandaran Wood and Paper Industries Company. For the OCC pulp,old corrugated containers were collected throughout Sari city after removing printed and gluedparts or unwanted objects. Then, the containers were split by hand into similar small parts in order to prevent cutting of the fibers. Afterwards, the OCC pulp was prepared from them. Handsheet papers of 127 g/m2 base weight were prepared from mixing of the NSSC pulp with the OCC pulp in contents of 60, 70, 80 and 100%. Mechanical properties of the produced papers including tensile strength, burst strength, tearing strength and crushing strength were then compared with each other in corrugated case, while squeezing strength was evaluated in ring case using TAPPI standard. The obtained results indicated that increasing consumption of the OCC up to 30%, improves tensile strength, tear strength and burst strength of the handsheet papers significantly in comparison with the control sample (for 21, 25 and 59%, respectively).However, crushing strength in the corrugated case and squeezing strength in the ring case were degraded about 13 and 9%, respectively. The results of this study revealed that mixing 30% of the OCC with the NSSC could yield papers of higher quality.