Date of Award


Degree Name

Bachelor of Science


Paper Science and Engineering


The purpose of this thesis was to study the effects of temperature and concentration of retention aids on retention. This had been a debatable issue between northern and southern paper mills because of their temperature differences.

The retention studies were performed with the dynamic drainage jar and the pilot paper machine at Western Michigan University with good agreement in both cases.

It was found that increasing temperature when using different retention aids had a considerable effect on first-pass retention. The effect of temperature on retention was found to depend on the ionic charge of the retention aid. The cationic polymer retention increased from 40°F to 70°F and then decreased from 70°F to 140°F. The anionic polymer retention decreased from 40°F to 80°F and then increased somewhat from 80°F to 140°F.

Temperature had an effect on retention drainage and many other factors which influence the wet end of a paper machine. This was shown in this study which was designed to make proper use of the theory of zeta potential - the electrokinetic charge on a colloidal particle. In the development of Britt's dynamic drainage jar, the purpose was to study the effect of colloidal factors in isolation from hydromechanical factors to the largest possible extent. In this study the charge of the polymer was shown to be the most important factor in retention as temperature increased.