Tack and bonding strength of carbohydrate-based adhesives from different botanical sources

Modified and unmodified starch extracted from root crops, cereals and a legume have been assessed as bases for adhesives for paper-paper, paper-cardboard, paper-metal and paper-glass substrates. Adhesives based on unmodified starch from all the crops investigated produced low or high tack for paper-paper and paper-cardboard depending on the intensity of mechanical action/heat applied in the formulation process. None of the starches produced good tack for paper-metal and paper-glass. Adhesives based on starch from yam, cassava, potatoes and corn modified by acid moisturing and roasting produced high tack and bonding strength for paper-paper and paper-glass, The effect of modification on these properties is attributable to the decrease in molecular size of the glycosidic chain or starch. (C) 2002 Elsevier Science Ltd. All rights reserved.