Decay resin impregnated wood

The impregnation of PF (phenol-formaldehyde) resin into wood was studied in the early part of the twentieth century. PF resin wood composites have been commercialized as Impreg and Compreg for their high mechanical strength and dimensional stability. Although the enhancement of decay resistance by PF resin treatment was also found earlier [1], it has not been applied to wood preservation techniques for the prevention of biodeterioration. 

Most ancient wooden objects recovered in archaeological excavations are usually in a decayed, weak, and friable condition that requires stabilization before the objects can be safely handled and studied. Stabilization of wood and decayed wooden objects, generally includes the use of consolidants, liquid solutions of a resin that impregnates and fills gaps in the wood and on drying solidifies, strengthening its fragile, deteriorated structure (Thompson 1991 Rowell and Barbour 1990). 

Although Stamm and Baechler [1] reported that 70% of ASE was required to eliminate decay in PF resin treatment, our results showed that a far smaller ASE (20-35%) was enough to eliminate decay when treating with Mn 369 and Mn 621 resins at only 5% of WPG. This suggests that the elimination of decay by the impregnation of low molecular weight PF resin can be involved with some additional factor such as the formation of bioactive polymers in the wood structure. 

Reduction of furfural leads to furfuryl alcohol 63 which can be easily transformed into resins, thus replacing phenol formaldehyde resins (Scheme 21) [115]. A recent apphcation concerns impregnation of wood (furfurylated wood). For instance, high retention of grafted or polymerized furfuryl alcohol improves a variety of properties such as an increased hardness, resistance to microbial decay and insect attack, as well as resistance to chemical degradaticai. Modulus of rupture (MOR), elasticity (MOE), and the dimensional stabihty are also significantly increased. 

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