Interaction between two oppositely charged starches in an aqueous medium containing suspended mineral particles as a basis for the generation of cellulose-compatible composites

The efficient use of renewable biopolymers or their composites in the manufacture of lignocellulosic products fits well into the concept of sustainability. In this study, the process concept of forming starch mineral composites induced by inter-polymer interaction between two oppositely charged, sustainable biopolymers (i.e cationic starch and anionic starch) for enhancing the compatibility and hydrogen-bondability of mineral filler particles with cellulosic fibers was preliminarily demonstrated. Interestingly, a pronounced synergy between cationic starch and anionic starch favorable for enhancement of both filler retention and filler bondability was identified. The weight ratio of cationic starch to anionic starch was a critical parameter. Under the conditions studied, a ratio of 17-3 was particularly favorable for improving filler-fiber interaction. The combination of starch-based polyelectrolyte complexes with existing mineral filler technology may provide a low-cost, easily scalable, and efficient strategy for consolidation of mineral-containing cellulosic networks. (V) 2016 Elsevier B.V. All rights reserved.