Date of Award


Degree Name

Bachelor of Science


Pulp and Paper Technology

First Advisor

Dr. S. Kukolich


The effects of pH on alkaline sizing of two bleached hardwood pulps, kraft and sulfite, was investigated. The pulps were refined in a Noble and Wood cycle beater and handsheets were made with a Noble and Wood handsheet making system. The handsheets were internally sized with 0.15 percent Aquapel using 0.05 percent Kymene 557 as a retention aid. Upon varying the pH of sizing of bleached hardwood sulfite pulp the Hercules Ink Photometer measurements of 258, 636, and 563 seconds were observed at pH's of 7.0, 8.5, and 9.5 respectively. The sizing increased with pH up to a certain pH value and then decreased with a further increase in pH. The Ink Photometer measurements were higher for bleached hardwood kraft pulp, 291 seconds at 7.0 pH and 846 at 8.5 pH, indicating a higher alkaline sizing efficiency for the bleached kraft pulp over this pH range.