Maple lignin

Similar studies were conducted by Kudzin and Nord (64) on the hardwoods oak, birch and maple. The fungus employed to bring about the decay of these wood samples was Daedalea quercina. The results of the periodic analyses of the decayed wood and the chemical compositions of the alcohol extractable lignins are outlined in Tables 6 and 7 respectively. 

Consequently, the native and enzymatically liberated lignins from white Scots pine, oak, birch, maple, kiri1 wood and bagasse were oxidized with nitrobenzene in alkali. The method of Stone 113) was applied quantitatively in this study. The amount of each degradation product obtained from each of the lignins is listed in Table 12 110). 

Fig. 5 A—D. A White Scots Pine Native Lignin B Birch Native Lignin C Oak Native Lignin D Maple...

Evaluation of lignin-modified resins used to bond maple blocks and... 

It has been demonstrated that red oak OSL could be used to replace 35% to 40% of the phenol (or phenolic resin solids) in phenol-formaldehyde resins used to laminate maple wood and to bond southern pine flake boards (wafer-board and/or strandboard) without adversely affecting the physical bond properties. While this pulping process and by-product lignin do not commercially exist at this time in the United States, lignins from such processes are projected to cost 40% to 50% less than phenol as a polymer raw material. 

Resin Preparation. Two approaches to resin preparation were used with regard to the initial stages of condensation, depending on whether the resin was intended for laminating maple blocks or for bonding southern pine flake boards. For maple block resins, the steps involved were as follows addition of water, sodium hydroxide (optional) and lignin, which were heated and... 

Sterijades, R., Dean, J. F. D., Gamble, G., Himmelsbach, D. S., and Eriksson, K.-E. L., 1993, Extracellular laccase and peroxidases from sycamore maple (Acer pseudoplatanus) cell suspension cultures. Reactions with monolignols and lignin model compounds, Planta 190 75-87. 

A wide range of phenolic compounds, varying in type and concentration, can also be found in maple sap (Dumont, 1994). Most of these appear to be derived from lignin (Kermasha et ah, 1995). They range in concentration in sap up to 0.1 ppm. The most dominant phenols present tend to... 

Hydrogenolysis has also found use in a lignin biosynthesis study in which 14C-labeled lignin precursors were administered to wheat plants and maple twigs and ultimately recovered in the form of the typical lignin hydrogenolysis products, dihydroconiferyl and dihydrosinapyl alcohols (Brown and Neish 1959). 

Bhaskaran TA, Schuerch C (1969) A study of non volatile hydrogenated maple wood lignin TAPPI 52 1948-1952... 

Bhattacharya A, Schuerch C (1960) Lignin from the alkaline hydrogenation of sugar maple-wood III Chromatographic separation of higher molecular weight fractions and a structural study TAPPI 43 840-844... 

Brewer C, Cooke LM, Hibbert H (1948) Studies on lignin and related compounds LXXXIV The high pressure hydrogenation of maple wood J Am Chem Soc 70 57-59... 

Granath M, Schuerch C (1953) Preliminary separation of maple hydrol lignin J Am Chem Soc 75 707-709... 

Without extraction with polar solvents the Nq/Nq ratios were regularly much lower. These ratios were well below those of cellulose and lignin for maple wood and pine wood, amounting to 0.15 and 0.26, respectively. The extraction effect was due to nonpolar wood extractives no effort has been made to identify these extractives. Although the likelihood of extractives covering the surface cannot be... 

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