Abstract The substitution of phenol in phenol-formaldehyde (PF) resins used for wood modification with renewable lignin cleavage products (LCP) can reduce non-renewable resource consumption. Previous studies indicate that replacing 30–40 % of the phenol in PF resins yields high performance wood products, but the effect on soft-rot resistance has not yet been studied. In this study, 30 % of phenol in a PF resin was substituted by softwood kraft LCP from pyrolysis. Scots pine sapwood ( Pinus sylvestris ) and European beech wood ( Fagus sylvatica ) were modified with the resin by impregnation and curing. Resistance to soft-rot was determined according to CEN/TS 15083-2 (2005) in laboratory-based terrestrial microcosm tests. The resin-treated wood specimens showed oven-dry mass loss below 0.5 %, indicating a high durability (durability class 1), with no significant difference between PF and LCP-PF resins. The results indicate that a high-performance wood modification is possible, while reducing the use of non-renewable phenol.
Karthäuser et al. (Sat,) studied this question.