Molded Pulp, Chemical Aspects Webinar – Part 2: Fluid holdout (hydrophobic sizing)
Molded pulp items are often used to hold fluids, as in the case of a paper plate. But cellulosic fibers have a hydrophilic nature. The ability of a molded pulp item to resist fluids can be achieved by a combination of chemical and physical approaches. This webinar briefly covers some of the main chemical treatments, including rosin and AKD sizing agents and their use. Some options for surface application will be considered too. In principle, the hold-out of liquids depends on the sizes of pores within the material, which can depend on the level of refining. The last topic of the webinar is a possible role of nanocellulose and other components for a layer applied to the surface of a molded pulp product. By such application it is possible, in principle, to achieve barrier properties against the diffusion of oxygen, as long as the product is also treated to resist moisture.
Speaker: Martin Hubbe, North Carolina State University
Martin Hubbe, born in the papermaking town of Millinocket, Maine, earned a Masters degree at the Institute of Paper Chemistry (Appleton, WI, 1979), and a Ph.D. in chemistry at Clarkson University (Potsdam, NY, 1984). After a total of 15 years in corporate research (at American Cyanamid Corp., then International Paper), Hubbe joined North Carolina State University in 1998. As Professor and Buckman Distinguished Scientist, Hubbe teaches and conducts research related to the colloidal chemistry of cellulosic materials, with a particular focus on papermaking wet-end chemistry. Hubbe has conducted research related to paper strength, electrokinetic tests, flocculation, and dewatering. He also has chaired TAPPI’s “Introduction to Wet-End Chemistry” short course and conducted university courses for on-campus students and distance-education. The peer-reviewed scientific journal BioResources, which he co-founded and edits with Dr. Lucia, currently publishes more scientific articles than any other publication devoted to the materials science of paper and wood.