• Alkali Lignin
  • Hexamethylene tetramine derivatives of alkali lignins are formed by reacting, at a temperature between 70° C. and 180° C., 0.17 to 2.0 moles of a hexamethylene tetramine forming solution with 1 mole of an alkali lignin solubilized in an alkaline solution. (freepatentsonline.com)
  • 1. Derivatives of lignin obtained by reacting in an alkaline solution an alkali lignin with from 0.17 to 2.0 moles of hexamethylene tetramine per mole of lignin at a temperature between 70° and 180° C., said derivative dried to form products having large surface areas. (freepatentsonline.com)
  • 3. The derivatives of claim 1 wherein said alkali lignin is a demethylated lignin. (freepatentsonline.com)
  • 5. The process of producing large surface area lignin derivatives which comprises, reacting in an aqueous medium an alkali lignin with from 0.17 to 2.0 moles of hexamethylene tetramine per mole of lignin at a temperature between 70° and 180° C., mixing said product with varsol and acetic acid, and drying said mixture. (freepatentsonline.com)
  • More particularly, this invention relates to hexamethylene tetramine derivatives of alkali lignin that are useful as stabilizers and emulsifiers and are easily dried to lignins having large surface area. (freepatentsonline.com)
  • According to the present invention it is possible to obtain lignin derivatives, which are capable of obtaining high surface areas upon proper drying, by reacting in an aqueous alkaline solution an alkali lignin with hexamethylene tetramine. (freepatentsonline.com)
  • The lignins employed in this invention are of the type known as "alkali lignin" obtained from the black liquor formed during the manufacture of pulp by the sulfate or "kraft" process. (freepatentsonline.com)
  • It is not necessary to start with an alkali lignin per se as modified alkali lignins, such as the demethylated lignins made according to U.S. Pat. (freepatentsonline.com)
  • enzyme
  • Wang Z. Y. Lignin deposition and associated changes in anatomy, enzyme activity, gene expression and ruminal degradability in stems of tall fescue at different developmental stages. (springer.com)
  • enzymatic
  • The terms ligninases and lignases are older names for the same class, but the name "lignin-modifying enzymes" is now preferred, given that these enzymes are not hydrolytic but rather oxidative (electron withdrawing) by their enzymatic mechanisms. (wikipedia.org)
  • These enzymes have been used in the refinement of poplar as lignin inhibits the enzymatic hydrolysis of treated poplar and Lignin-modifying enzymes can efficiently degrade the lignin thus fixing this problem. (wikipedia.org)
  • fungi
  • Part of that is the machinery to break down wood became simpler since brown rot fungi are not breaking down lignin. (redorbit.com)
  • Lignin-modifying enzymes (LMEs) are various types of enzymes produced by fungi and bacteria that catalyze the breakdown of lignin, a biopolymer commonly found in the cell walls of plants. (wikipedia.org)
  • Laccases, which are multicopper oxidases, are another class of enzymes found in both bacteria and fungi which have significant lignin-degrading properties. (wikipedia.org)
  • crops
  • Both mapping of quantitative trait loci and transgenic approaches have been adopted to modify lignin in crops. (hindawi.com)
  • Reduction of lignin in biofuel crops by genetic engineering is likely one of the most effective ways of reducing costs associated with pretreatment and hydrolysis of cellulosic feedstocks, although some potential fitness issues should also be addressed. (springer.com)
  • Modified lignin could make fibrous crops more digestible, allowing producers to feed more forage crops and less grain to their livestock. (allaboutfeed.net)
  • cell walls
  • Using plants and trees to make products such as paper or ethanol leaves behind a residue called lignin, a component of plant cell walls. (phys.org)
  • Grabber and his colleagues first tested the effects of changing the cell walls in a laboratory--before applying those changes to live plants--by incorporating a chemical compound called coniferyl ferulate into lignin formed within cell walls. (allaboutfeed.net)
  • Lignins are particularly important in the formation of cell walls, especially in wood and bark, because they lend rigidity and do not rot easily. (wikipedia.org)
  • The polysaccharide components of plant cell walls are highly hydrophilic and thus permeable to water, whereas lignin is more hydrophobic. (wikipedia.org)
  • phenol-formaldehyde
  • Lignin recovered from the hot-water extract of sugar maple ( Acer saccharum ) is used in this study to synthesize adhesive blends to replace phenol-formaldehyde (PF) resin. (mdpi.com)
  • biofuel
  • Lignin is a bulky chain of molecules found in wood and is usually discarded during biofuel production. (phys.org)
  • Dixon R. A. Lignin modification improves fermentable sugar yields for biofuel production. (springer.com)
  • alkaline
  • Four dioxane lignins from kenaf have been subjected to alkaline hydrolysis, and the presence of esterified p-coumaric and p-hydroxybenzoic acids in them has been shown. (springer.com)
  • Lignin was first mentioned in 1813 by the Swiss botanist A. P. de Candolle, who described it as a fibrous, tasteless material, insoluble in water and alcohol but soluble in weak alkaline solutions, and which can be precipitated from solution using acid. (wikipedia.org)
  • dicot
  • lignins from gymnosperms are composed of G-units only (with minor amounts of H-units), whereas angiosperm dicot lignins are composed of G- and S-units. (plantphysiol.org)
  • processes
  • What we have right now with current bioconversion processes often resembles a white rot approach," he said, "attacking lignin to get at carbohydrates and then converting them to fuels, chemicals or paper. (redorbit.com)
  • It is important to note that sulfur bearing lignins are commercialized whereas sulfur-free lignins are not because of lack of industrial processes. (transparencymarketresearch.com)
  • Although these drying processes are adaptable to various lignin modifications, they are particularly suitable for use with the products of this invention. (freepatentsonline.com)
  • Technical lignins are lignins isolated from various biomasses during various kinds of technical processes such as wood pulping. (wikipedia.org)
  • molecular
  • The molecular weight distribution of the lignin and the blends are characterized by size exclusion chromatography (SEC). The effect of pH (0.3, 0.65 and 1), ex situ furfural, and curing conditions on the tensile properties of adhesive reinforced glass fibers is determined and compared to the reinforcement level of commercially available PF resin. (mdpi.com)
  • It is therefore a general object of this invention to provide a novel low cost, high melting point, high molecular weight lignin derivative. (freepatentsonline.com)
  • Lignins can be characterized by determination of their purity, molecular structure and thermal properties. (wikipedia.org)
  • molecules
  • Researchers accomplished this by reconstructing larger lignin molecules either through a chemical reaction with formaldehyde or by washing with methanol. (innovations-report.com)
  • Here, however, we attempted to reconstruct larger lignin molecules by a simple crosslinking chemistry and then used it as a substitute for rigid phase in a formulation that behaves like crosslinked rubbers that can also be processed like plastics," Naskar said. (innovations-report.com)
  • Crosslinking involves building large lignin molecules by combining smaller molecules where formaldehyde helps to bridge the smaller units by chemical bonding. (innovations-report.com)
  • coniferyl
  • Hatfield, Ralph and ARS geneticist Jane Marita at Madison are now leading efforts to engineer plants to make lignin with coniferyl ferulate. (allaboutfeed.net)
  • synthesis
  • Our work addresses a pathway to utilize lignin as a sustainable, renewable resource material for synthesis of thermoplastics that are recyclable," said Naskar, a member of the Department of Energy laboratory's Material Science and Technology Division. (innovations-report.com)
  • Goffner D. Lignins and lignocellulosics: a better control of synthesis for new and improved uses. (springer.com)
  • Enzymic synthesis of lignin precursors. (wikipedia.org)
  • carbon
  • Lignin from crop residues plays an important role in the soil organic carbon cycling, as it constitutes a recalcitrant carbon pool affecting nutrient mineralization and carbon sequestration. (hindawi.com)
  • Lignin constitutes 30% of non-fossil organic carbon and 20-35% of the dry mass of wood. (wikipedia.org)
  • Lignin plays a significant role in the carbon cycle, sequestering atmospheric carbon into the living tissues of woody perennial vegetation. (wikipedia.org)
  • commonly
  • It is commonly accepted that lignin evolved together with the adaptation of plants to a terrestrial life to provide them with the structural support needed for an erect growth habit ( Fig. 3 ). (plantphysiol.org)
  • agricultural
  • Lignin is a plant component with important implications for various agricultural disciplines. (hindawi.com)
  • However, breeding goals must be defined considering the conflicting role of lignin in different agricultural disciplines. (hindawi.com)
  • content
  • Untreated lignin is characterized by lignin content and nuclear magnetic resonance (NMR) analysis. (mdpi.com)
  • The lignin content can be defined as the sum of the amount of acid-insoluble matter and acid-soluble matter, absorbing at 205 nm, after sulphuric acid hydrolysis during specified conditions, as determined by gravimetry and spectrophotometry, in milligrams per gram. (wikipedia.org)
  • plant
  • Phys.org)-Lignin is an important component of the cell wall in plant cells and accounts for rigid structures, such as tree bark. (phys.org)
  • There, research agronomist John Grabber--working with ARS plant physiologist Ronald Hatfield, Fachuang Lu of the University of Wisconsin, and John Ralph, formerly with ARS and now at the University of Wisconsin--has designed lignin that breaks down more easily. (allaboutfeed.net)
  • Lignin plays a crucial part in conducting water in plant stems. (wikipedia.org)
  • organic
  • Lignin is a class of complex organic polymers that form important structural materials in the support tissues of vascular plants and some algae. (wikipedia.org)