Soda bagasse lignin

The alkali lignins used were selected from different industrial origins in order to have a wide variation in their properties. The lignins were a kraft softwood, soda/AQ hardwood and soda bagasse lignin (Table II). 

The soda bagasse lignin, on the other hand, is a very reactive industrial lignin as is indicated by its high number of unsubstituted 3- and 5-positions of 0.7/Cg on phenolic propanoid units. This lignin is only mildly condensed and contains 1.05 unsubstituted 3- or 5-positions. 

Figure 7. Reaction of soda bagasse lignin with formaldehyde in 1.0 hydrochloric acid in 23% aqueous dioxane at 80°C (—,-------) and in 0.4N...

However, lignin may find application as a suitable wood-composite adhesive in adhesive formulations if chemically modified in some manner. In this respect, the recent developments with soda bagasse lignin-resorcinol-formaldehyde and lignin-isocyanate adhesives allow for some cautious optimism for the future. 

Soda Bagasse Lignin Adhesives for Particleboard Preliminary Results... 

In this chapter, the development of a thermosetting adhesive from soda bagasse lignin is described. The research has concentrated on the development of interior-grade adhesives for particleboard. The local market for exterior boards is smaller than that for the interior panels, and adhesives for exterior boards are already covered by an excellent range of tannin-based adhesives. 

Table IV. Internal Bond Strength of Particleboard, 12-mm-Thick, Prepared from Soda Bagasse Lignin Adhesives (10% on Dry Chips) After Pressing at 170 °C for 15 Minutes...

Van der Klashorst, G. H Strauss, H. F. Properties and Potential Utilization of Industrial Soda Bagasse Lignin. Holzforschung 1986, 6, 375-382. 

Van der Klashorst, G. H Cameron, F. A Pizzi, A. The Utilization of Soda Bagasse Lignin in the Manufacture of Thermosetting Wood Adhesives. Paper presented at the International Symposium on Wood and Pulping Chemistry, April 1987. 

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