The variation of tangential rheological properties caused by shrinkage anisotropy and moisture content gradient in white birch disks
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Zongying Fu
Abstract
The focus of this study is the variation of practical shrinkage strain, elastic strain, viscoelastic creep strain, and mechanosorptive creep characteristics of white birch (Betula platyphylla Suk) disks caused by shrinkage anisotropy (ShrA) and its interaction with moisture content (MC) gradient. The rheological properties of white birch disks have been analyzed as a function of MC based on two different drying schedules at constant and increasing temperature. The drying conditions influence the strains remarkably. The stress characteristics and stress reversal mechanism under the conditions of increasing temperature are discussed based on stress analysis diagrams. Under both drying schedules, the wood disks are initially subjected to tangential tensile stress, and with decreasing MC, the tensile stress turns into compressive stress. Before stress reversal, the stresses of ShrA and MC gradient are aligned in the same direction and then point in opposite directions.
Acknowledgments
The project was supported by the National Natural Science Foundation of China grant no. 31270595.
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Articles in the same Issue
- Frontmatter
- Original Articles
- Study on the residual lignin in Eucalyptus globulus sulphite pulp
- Hydrogenolysis of lignin in ZnCl2 and KCl as an inorganic molten salt medium
- Synthesis of lignin polyols via oxyalkylation with propylene carbonate
- Preparation of water-dispersive poly(3,4-ethylenedioxythiophene) (PEDOT) conductive nanoparticles in lignosulfonic acid solution
- Properties of polyurethane (PUR) films prepared from liquefied wood (LW) and ethylene glycol (EG)
- Dynamic response of earlywood and latewood within annual growth ring structure of Scots pine subjected to changing relative humidity
- One-stage thermo-hydro treatment (THT) of hardwoods: an analysis of form stability after five soaking-drying cycles
- The variation of tangential rheological properties caused by shrinkage anisotropy and moisture content gradient in white birch disks
- Inheritance of basic density and microfibril angle and their variations among full-sib families and their parental clones in Picea glehnii
- Mechanical properties and chemical composition of beech wood exposed for 30 and 120 days to white-rot fungi
- Chemical improvement of surfaces. Part 3: Covalent modification of Scots pine sapwood with substituted benzoates providing resistance to Aureobasidium pullulans staining fungi
- Chemical and ultrastructural changes of ash wood thermally modified using the thermo-vacuum process: I. Histo/cytochemical studies on changes in the structure and lignin chemistry
- Chemical and ultrastructural changes of ash wood thermally modified (TMW) using the thermo-vacuum process: II. Immunocytochemical study of the distribution of noncellulosic polysaccharides
- Revisiting hardboard properties from the fiber sorting point of view
- Effects of acetylation and formalization on the dynamic water vapor sorption behavior of wood
- Immune-regulatory activity of methanolic extract of Acacia confusa heartwood and melanoxetin isolated from the extract
- Stereomicroscopic optical method for the assessment of load transfer patterns across the wood-adhesive bond interphase
Articles in the same Issue
- Frontmatter
- Original Articles
- Study on the residual lignin in Eucalyptus globulus sulphite pulp
- Hydrogenolysis of lignin in ZnCl2 and KCl as an inorganic molten salt medium
- Synthesis of lignin polyols via oxyalkylation with propylene carbonate
- Preparation of water-dispersive poly(3,4-ethylenedioxythiophene) (PEDOT) conductive nanoparticles in lignosulfonic acid solution
- Properties of polyurethane (PUR) films prepared from liquefied wood (LW) and ethylene glycol (EG)
- Dynamic response of earlywood and latewood within annual growth ring structure of Scots pine subjected to changing relative humidity
- One-stage thermo-hydro treatment (THT) of hardwoods: an analysis of form stability after five soaking-drying cycles
- The variation of tangential rheological properties caused by shrinkage anisotropy and moisture content gradient in white birch disks
- Inheritance of basic density and microfibril angle and their variations among full-sib families and their parental clones in Picea glehnii
- Mechanical properties and chemical composition of beech wood exposed for 30 and 120 days to white-rot fungi
- Chemical improvement of surfaces. Part 3: Covalent modification of Scots pine sapwood with substituted benzoates providing resistance to Aureobasidium pullulans staining fungi
- Chemical and ultrastructural changes of ash wood thermally modified using the thermo-vacuum process: I. Histo/cytochemical studies on changes in the structure and lignin chemistry
- Chemical and ultrastructural changes of ash wood thermally modified (TMW) using the thermo-vacuum process: II. Immunocytochemical study of the distribution of noncellulosic polysaccharides
- Revisiting hardboard properties from the fiber sorting point of view
- Effects of acetylation and formalization on the dynamic water vapor sorption behavior of wood
- Immune-regulatory activity of methanolic extract of Acacia confusa heartwood and melanoxetin isolated from the extract
- Stereomicroscopic optical method for the assessment of load transfer patterns across the wood-adhesive bond interphase
