Updating Starch Technologies for Corrugating Adhesive Use
- Jul 18, 2012
The Stein-Hall process has allowed aqueous starch adhesives to be prepared from insoluble granules since the 1930s. It's still widely used, and the choice of starch source plays a big role in adhesive performance. Stein-Hall and associated processes also continue to evolve as adhesive properties are optimized. In particular, the adhesives it produces have low solids content and therefore take time and/or energy to dry. They also have been used with formaldehyde resins to attain the highest levels of water resistance. But now, recent developments have tackled these issues. The Stein-Hall process uncoils amylose's helices to provide high-viscosity solutions that can be used to prepare aqueous adhesive compositions. It does so by cooking, or gelatinizing, starch in water so that its hydroxyl groups are freed to form a colloidal gel.