Waferboard, preparation

In order to evaluate the method, the three lignins were methylolated, formulated with R-PF resin and waferboards made. The boards were tested for dry MOR, MOE, wet MOR and IB, but only the last term was the pa rameter chosen for quality determinations by the authors. Limited number of testing results are given in Table III. The data are not corrected for board density. The pass level for Canadian requirements is IB = 0.345 MPa, so all of the boards prepared passed, even those containing binder with 50% of the PF resin replaced with methylolated lignin. 

These are prepared with specialist flaking equipment that can use small diameter logs. Initially this was from species having no other use, but as capacity has grown alternative wood sources have been used. The process evolved from the waferboard manufacture that used thin flakes or wafers to form a panel where the wafers performed as small veneers. The increased slenderness ratios of strands resulted in improvements in both strength and directional properties so that OSB became an alternative to plywood. The reduced width of the strands compared with wafers allowed them to be produced from smaller diameter wood. 

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