Activation of pine kraft lignin by Fenton-type oxidation for cross-linking with oligo(oxyethylene) diglycidyl ether
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Lars Passauer
,
Klaus Fischer
Abstract
Mechanically stable hydrogels featuring water absorption capacities of up to 75 gH2O ggel-1 can be obtained by cross-linking of activated technical lignins with poly(ethylene) glycol diglycidyl ether under strong alkaline conditions. Fenton oxidation prior to cross-linking by hydrogen peroxide and catalytic amounts of ferrous chloride has been found to be superior to an alkaline H2O2 pre-treatment with respect to gel formation, water sorption, and rheological properties of the resulting oligo(oxyethylene) lignin gels. Purified pine kraft lignin undergoes in the course of Fenton oxidation hydroxylation of both aliphatic and aromatic moieties. This is the main reason for the enhanced cross-linking density obtained after treatment with poly(ethylene) glycol diglycidyl ether. The oxidative changes have been demonstrated by principal component analysis of Curie point pyrograms, wet chemical methods, FT-IR, and 31P NMR spectroscopy. Cleavage of side-chains, radical 5,5′-coupling of phenylpropane units, formation of carbonyl and carboxyl groups, and cleavage of aromatic rings were observed. These structural changes may increase or decrease the water sorption capability of the cross-linked products.
©2011 by Walter de Gruyter Berlin New York
Articles in the same Issue
- Publisher’s Note
- Publisher’s Note
- ORIGINAL ARTICLES
- Brightness reversion of eucalyptus kraft pulp: Effect of carbonyl groups generated by hypochlorous acid oxidation
- MgSO4 vs. Mg(OH)2 as a cellulose protector in oxygen delignification
- Hydrogen peroxide and supercritical carbon dioxide: a new bleaching stage for Eucalyptus kraft-O2 pulps
- Preparation and physical characterization of strongly swellable oligo(oxyethylene) lignin hydrogels
- Activation of pine kraft lignin by Fenton-type oxidation for cross-linking with oligo(oxyethylene) diglycidyl ether
- Determination of pectin content of eucalyptus wood
- Theory of transport processes in wood below the fiber saturation point. Physical background on the microscale and its macroscopic description
- The effect of galactan content on the mechano-sorptive strain in loblolly pine
- Genetic and environmental variation in heartwood colour of Australian blackwood (Acacia melanoxylon R.Br.)
- Aging of wood: Analysis of color changes during natural aging and heat treatment
- Thermal behaviour of Norway spruce and European beech in and between the principal anatomical directions
- Air-coupled ultrasound inspection of glued laminated timber
- Optical characteristics of wood investigated by time-of-flight near infrared spectroscopy
- Comparison of NDE techniques for assessing mechanical properties of unjointed and finger-jointed lumber
- Potential of pulp and paper sludge as a formaldehyde scavenger agent in MDF resins
- FT-IR imaging microscopy to localise and characterise simultaneous and selective white-rot decay within spruce wood cells
- Effects of ionic strength, monoethanolamine, copper, and pH on adsorption of alkyl dimethyl benzyl ammonium chloride in wood
- Long-term performance of fused borate rods for limiting internal decay in Douglas-fir utility poles
- SHORT NOTE
- Composition of the heartwood essential oil of incense cedar (Calocedrus decurrens Torr.)
- Meetings
- Meetings
Articles in the same Issue
- Publisher’s Note
- Publisher’s Note
- ORIGINAL ARTICLES
- Brightness reversion of eucalyptus kraft pulp: Effect of carbonyl groups generated by hypochlorous acid oxidation
- MgSO4 vs. Mg(OH)2 as a cellulose protector in oxygen delignification
- Hydrogen peroxide and supercritical carbon dioxide: a new bleaching stage for Eucalyptus kraft-O2 pulps
- Preparation and physical characterization of strongly swellable oligo(oxyethylene) lignin hydrogels
- Activation of pine kraft lignin by Fenton-type oxidation for cross-linking with oligo(oxyethylene) diglycidyl ether
- Determination of pectin content of eucalyptus wood
- Theory of transport processes in wood below the fiber saturation point. Physical background on the microscale and its macroscopic description
- The effect of galactan content on the mechano-sorptive strain in loblolly pine
- Genetic and environmental variation in heartwood colour of Australian blackwood (Acacia melanoxylon R.Br.)
- Aging of wood: Analysis of color changes during natural aging and heat treatment
- Thermal behaviour of Norway spruce and European beech in and between the principal anatomical directions
- Air-coupled ultrasound inspection of glued laminated timber
- Optical characteristics of wood investigated by time-of-flight near infrared spectroscopy
- Comparison of NDE techniques for assessing mechanical properties of unjointed and finger-jointed lumber
- Potential of pulp and paper sludge as a formaldehyde scavenger agent in MDF resins
- FT-IR imaging microscopy to localise and characterise simultaneous and selective white-rot decay within spruce wood cells
- Effects of ionic strength, monoethanolamine, copper, and pH on adsorption of alkyl dimethyl benzyl ammonium chloride in wood
- Long-term performance of fused borate rods for limiting internal decay in Douglas-fir utility poles
- SHORT NOTE
- Composition of the heartwood essential oil of incense cedar (Calocedrus decurrens Torr.)
- Meetings
- Meetings
