Alkali Treated Kraft Lignin as a Component in Flakeboard Resins

Wood production, wood technology, and biotechnological impacts

“…Formaldehyde from the PF resin may act in such mixtures as a cross-linker between the reactive sites of the technical lignins and the synthetic phenol binder (Kuo et al 1991, Vázquez et al 1999. As first suggested by , radical polymerisation of the technical lignins (lignosulphonate) set off by oxidative enzymes is an alternative way of cross-linking (Kharazipour et al 1998b.…”

“…As the lignins on fibre surfaces, technical lignins are not as reactive and are therefore normally not applied as pure binder but as extenders for improving board properties, particularly the swelling properties. Chemical, electrochemical or enzymatic treatments prior to application as a binder can overcome at least partially the reaction problems , Medvedev et al 1985, Glasser 1989, Kuo et al 1991,b, Chen & Wu 1994, Krumbiegel 2002. Costs of such pretreatments and type and profitability of the wood composite products will however limit their applications in industry.…”

“…Formaldehyde from the PF resins is thought to act in such blends as a cross-linker between the reactive sites of the technical lignins and the synthetic phenol binder (Kuo et al 1991, Vázquez et al 1999. Many studies on replacing parts of conventional PF-and also UF binders have been published and reviewed in the literature , Abe 1987, Lewis & Lantzky 1989, Shiraishi 1989, Roffael & Dix 1991,b, Lisperguer & Solis 1999, Lisperguer et al 2000, Feldman 2002, Turunen et al 2002, Tejado et al 2007a; see also Chapter 18 of this book).…”

Some of the properties of oriented strandboard manufactured using kraft lignin phenolic resin

“…Replacing PF with an organic based resins such as lignin is one of the possible approaches to eliminate adverse formaldehyde emission of phenolic based resins (Cetin and Kazayawoko et al, 1992a;Lewis and Lantzy, 1987). Various studies have been carried out to find modified economically and environmentally applicable phenolic resins that can be used to manufacture structural wood based panels (Kuo et al, 1991;Lewis and Lantzy, 1987;Lora et al, 1994). Lignin is one of components to produce such modified binders (Danielson and Simonson, 1997;Turunen et al, 2003).…”

“…Glasser (1989) showed that high degree of lignin incorporation into thermosetting material can be achieved by modification of lignin. Lignin can be hydrolyzed in alkaline or acidic condition which degrades lignin molecules generating new phenolic hydroxyl groups (Kazayawoko et al, 1992b;Kuo et al, 1991). One of the advantages of using alkaline hydrolyzes to modify kraft lignin is to use such products directly in phenolic resin synthesis Sellers et al, 1994;Ors and Kalaycioglu, 1987).…”