Abstract
The industrially produced chemical pulps have lower strength properties than those obtained under laboratory conditions, and this difference is referred to as the strength delivery (SD) problem. In this study, the hypothesis was put forward that the SD could, at least in part, be accounted for by the supramolecular structure of the cellulose microfibrils of the fiber wall. To test the hypothesis, two bleached softwood kraft pulps (BSKP) were manufactured from the same starting material with different degrees of cellulose aggregation, but the pulps were otherwise as similar as possible in other controllable respects. The chemical and physical properties, including the pulp strength, were tested. A selective increase of the degree of cellulose microfibril aggregation resulted in a pulp with a decreased tear index (TI) at a specified tensile index, and this decrease was similar in magnitude to what is typically encountered in SD. Accordingly, the current experimental study succeeded in mimicking the SD problem. The lateral fibril aggregate dimensions (LFAD) seem to play a pivotal role and it can be safely concluded in general that the supramolecular structure of cellulose in the fibers may be an important factor contributing to the SD problem.
Acknowledgments
Örjan Hedenberg, Stig Anderson, and Rose-Marie Karlsson are gratefully acknowledged for contributing with their great experimental skills in preparing the used pulps.
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©2014 by De Gruyter
Articles in the same Issue
- Frontmatter
- Original Articles
- Influence of cellulose supramolecular structure on strength properties of chemical pulp
- Morphological, mechanical, and optical properties of cypress papers
- Determination of ion exchange constants for pairs of metal ions to lignocellulosic materials by column chromatography
- Combustion behavior of oak wood (Quercus mongolica L.) modified by 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU)
- Synthesis and antifungal activity of camphoric acid-based acylhydrazone compounds
- Lignification of ray parenchyma cells in the xylem of Pinus densiflora. Part I: Microscopic investigation by POM, UV microscopy, and TOF-SIMS
- Lignification of ray parenchyma cells in the xylem of Pinus densiflora. Part II: Microchemical analysis by laser microdissection and thioacidolysis
- Distribution of lignin in vascular bundles of coconut wood (Cocos nucifera) by cellular UV-spectroscopy and relationship between lignification and tensile strength in single vascular bundles
- Compression properties of vascular boundles and parenchyma of rattan (Plectocomia assamica Griff)
- Properties of wood-plastic composites (WPCs) reinforced with extracted and delignified wood flour
- Anisotropic elastic properties of common ash (Fraxinus excelsior L.)
- Destructive and non-destructive evaluation of seven hardwoods and analysis of data correlation
- Experimental validation of green wood peeling assisted by IR heating – some considerations of the analytical system design
- The influence of felling season and log-soaking temperature on the wetting and phenol formaldehyde adhesive bonding characteristics of birch veneer
- Comparative evaluation of various lignin determination methods on hemicellulose-rich fractions of spruce and birch obtained by pressurized hot-water extraction (PHWE) and subsequent ultrafiltration (UF)
- Conversion between basic density and apparent density at any moisture content in Eucalyptus grandis
- Postpeak residual capacity of nailed connections of a shear wall
- Obituary
- Memorial on Horst H. Nimz (1930–2013)
Articles in the same Issue
- Frontmatter
- Original Articles
- Influence of cellulose supramolecular structure on strength properties of chemical pulp
- Morphological, mechanical, and optical properties of cypress papers
- Determination of ion exchange constants for pairs of metal ions to lignocellulosic materials by column chromatography
- Combustion behavior of oak wood (Quercus mongolica L.) modified by 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU)
- Synthesis and antifungal activity of camphoric acid-based acylhydrazone compounds
- Lignification of ray parenchyma cells in the xylem of Pinus densiflora. Part I: Microscopic investigation by POM, UV microscopy, and TOF-SIMS
- Lignification of ray parenchyma cells in the xylem of Pinus densiflora. Part II: Microchemical analysis by laser microdissection and thioacidolysis
- Distribution of lignin in vascular bundles of coconut wood (Cocos nucifera) by cellular UV-spectroscopy and relationship between lignification and tensile strength in single vascular bundles
- Compression properties of vascular boundles and parenchyma of rattan (Plectocomia assamica Griff)
- Properties of wood-plastic composites (WPCs) reinforced with extracted and delignified wood flour
- Anisotropic elastic properties of common ash (Fraxinus excelsior L.)
- Destructive and non-destructive evaluation of seven hardwoods and analysis of data correlation
- Experimental validation of green wood peeling assisted by IR heating – some considerations of the analytical system design
- The influence of felling season and log-soaking temperature on the wetting and phenol formaldehyde adhesive bonding characteristics of birch veneer
- Comparative evaluation of various lignin determination methods on hemicellulose-rich fractions of spruce and birch obtained by pressurized hot-water extraction (PHWE) and subsequent ultrafiltration (UF)
- Conversion between basic density and apparent density at any moisture content in Eucalyptus grandis
- Postpeak residual capacity of nailed connections of a shear wall
- Obituary
- Memorial on Horst H. Nimz (1930–2013)