Effect of EDC/ADH fibre crosslinking on the wet-web strength of bhkp with and without PCC loading

There has been very little success in trying to provide a method that increases the wet-web strength (WWS) of paper, even though it determines to a large extent the runnability of a papermaking machine. 1-ethyl-3-[3- (dimethylaminopropyl)] carbodiimide (EDC) has been shown to promote the crosslinking of soluble polysaccharides containing carboxyl groups [1-3]. In this work we use beaten hardwood Kraft pulp to show the enormous increase in WWS that can be obtained by crosslinking the fbres with EDC/adipic dihydrazide (ADH) after attachment of carboxymethyl cellulose to the fbres. Further, we show that such and increase in strength is very benefcial for highly precipitated calcium carbonate (PCC) loaded papers. Results prove the ability of EDC to promote covalent bonding in wet conditions makes it an excellent WWS agent.