Investigation of the properties of alkline peroxide mechanical pulp(APMP) from Cotton Stalk

This study was conducted to investigate the properties of cotton stalks APMP pulp. APMP prepared from chipped cotton stalks. the pulps were prepared separately from debarked and bark containing stalks using three two-stage treatments.Sodium hydroxide charge as a constant level of 4% and hydrogen peroxide at three levels of 0, 1 and 2% were used in to two-stages, sodium hydroxide as a constant level of 2% and hydrogen peroxide at three levels of 2, 3, 4% were applied. Other conditions of pulping was time's of 20 min for first stage and 100 min for second stage, temperature 70°C and l/w:6:1 as fixed factors considered. Pulp yield determined after neutralization and defiberation. All the pulps were refined up to 300 (ml, CSF) freeness and handsheets were made, then and properties of papers measured using TAPPI standards. Results showed that the pulp yield and brightness was higher in free-bark compared to bark-containing conditions. Also paper produced in free-bark condition with cotton stalks core, resulted the higher tensile and burst indexes and higher breaking length compared to whole cotton stalk.While tear index didn’t show significant difference.Generally, caliper and bulk rates were high in total treatments (free-bark and bark-containing conditions) from cotton stalk APMP process