Effects of oxidized recycled fibers on paper properties

• Main Authors: Mania Jadidi, Noraldin Neghad, Majid Zabihzadeh
• Format: Article
• Language: fas
• Published: Regional Information Center for Science and Technology (RICeST) 2012-09-01
• Series: تحقیقات علوم چوب و کاغذ ایران
• Subjects: Waste fiber; hydrogen peroxide; cationic starch; Paper properties
• Online Access: http://ijwpr.areeo.ac.ir/article_116105_060d2204d06e0b41473b7b384eafbff0.pdf

This research was conducted to find a procedure to increase the optical and strength properties of papers made from oxidized waste newspaper fibers. Samples of waste newspapers were randomly selected and deinked, then one part of deinked pulp was refined.  Both refined and unrefined recycled pulp were divided into two groups. In each case, a group of pulps was used to make standard hand sheets (control samples) without hydrogen peroxide treatment and only adding  2% cationic starch. Second group was subjected to  different percentages of hydrogen peroxide (2%, 3% & 4%) in alkaline conditions, then 2% cationic starch was added  to oxidized fibers prior to hand sheeting preparation and then standard hand sheets were made. Opticaland strength properties of all hand sheets were determined according to TAPPI standards. Also FTIR spectra was taken to specify the effect of oxidation on surfaces of pulp fibers. Results showed that treatment with oxidizing agent  increased the strength indices of papers. This increase was more evident when 3% hydrogen peroxide was applied. The  strengths of the control samples were the lowest. Moreover, refining imposed the positive effect on strength properties. Results of optical properties measurements indicated that as the extent of treatment for both refined and unrefined pulps increases, the brightness increased, and both the yellowness and opacity decreased. The highest brightness was reached when 3% peroxide was used. Also refining results in increased in brightness and yellowness  but decreas opacity.  FTIR spectra showed that samples of oxidized pulp had the greatest absorption at wave  number of 1650 which pertains to carboxyl group.