SEM Study of Tension Wood Fiber Morphology and its Effect on Paper Properties

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079061 ◽

1977 ◽

Vol 35 ◽

pp. 308-309

Author(s):

K. W. Robinson

Keyword(s):

Tension Wood ◽

Wood Fiber ◽

Strength Properties ◽

Fiber Morphology ◽

Paper Properties ◽

Pure Cellulose ◽

Short Rotation ◽

Hardwood Trees ◽

Sem Study

Tension wood (TW) is an abnormal tissue of hardwood trees; although it has been isolated from most parts of the tree, it is frequently found on the upper side of branches and leaning stems. TW has been classically associated with geotropic alignment, but more recently it has been associated with fast growth. Paper made from TW is generally lower in strength properties. Consequently, the paper industries' growing dependence on fast growing, short- rotation trees will result in higher amounts of TW in the final product and a corresponding reduction in strength.Relatively few studies have dealt with the role of TW in the structure of paper. It was suggested that the lower strength properties of TW were due to a combination of factors, namely, its unique morphology, compression failures in the cell wall, and lower hemicellulose content. Central to the unique morphology of the TW fiber is the thick gelatinous layer (G-layer) composed almost entirely of pure cellulose.

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Recycling of Waste MDF by Steam Refining: Evaluation of Fiber and Paper Strength Properties

Waste and Biomass Valorization ◽

10.1007/s12649-021-01391-4 ◽

2021 ◽

Author(s):

Sebastian Hagel ◽

Jesan Joy ◽

Gianluca Cicala ◽

Bodo Saake

Keyword(s):

Strength Properties ◽

Steam Treatment ◽

High Yield ◽

Medium Density ◽

Paper Strength ◽

Fiber Morphology ◽

Steam Refining ◽

Paper Test ◽

Paper Properties ◽

Intimate Knowledge

AbstractCurrently, most of the collected waste medium-density fiberboards (MDF) is incinerated or landfilled, as economically viable recycling methods are yet to be developed. By steam refining waste medium-density fiberboards (MDF), it is possible to hydrolyze the incorporated resins and isolate a high yield fiber fraction. Further refining of the steam treated fibers might enable the fibers to be utilized in applications such as paper packaging, facilitating a cascading use of the waste material stream. To this end, intimate knowledge of the material is needed. In this study, the steam refined fibers of two waste MDF samples containing differing amounts of softwood and hardwood underwent refining and beating. The resulting fibers were characterized regarding their morphology and paper test sheets were produced to evaluate their strength (compression-, tensile- and tear-strength). Distinct differences in response to refining between the MDF samples were apparent. For the sample with the higher hardwood share an increase in strength properties with increasing steam treatment severities could be observed and it was possible to produce test sheets with comparable compression strength to recycled pulp for industrial corrugated paperboard. For the sample with a higher share of softwood, the steam treatment severity did not show any influence on fiber morphology or paper properties, and the resulting paper strength was low in comparison to the other steam refined waste MDF sample. Graphic Abstract

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Does kraft hardwood and softwood pulp viscosity correlate to paper properties?

TAPPI Journal ◽

10.32964/tj15.10.643 ◽

2016 ◽

Vol 15 (10) ◽

pp. 643-651 ◽

Cited By ~ 1

Author(s):

ROBERT J. OGLESBY ◽

HUMPHREY J. MOYNIHAN ◽

RICARDO B. SANTOS ◽

ASHOK GHOSH ◽

PETER W. HART

Keyword(s):

Physical Properties ◽

Strength Loss ◽

Strength Properties ◽

Clear Correlation ◽

Paper Properties ◽

Physical Strength ◽

Pulp Viscosity ◽

Softwood Pulp ◽

The Impact ◽

Multiple recycling of paperboard: Paperboard characteristics and maximum number of recycling cycles— Part I: Multiple recycling of corrugated base paper

TAPPI Journal ◽

10.32964/tj18.11.631 ◽

2019 ◽

Vol 18 (11) ◽

pp. 631-638

Author(s):

FREDERIC KREPLIN ◽

HANS-JOACHIM PUTZ ◽

SAMUEL SCHABEL

Keyword(s):

Compression Test ◽

Production Capacity ◽

Strength Properties ◽

Paper Properties ◽

Corrugated Board ◽

Laboratory Conditions ◽

Base Paper ◽

Study Results ◽

Short Span ◽

Multiple Recycling

Paper for recycling is an important fiber source for the production of corrugated base paper. The change in production capacity toward more and more packaging papers affects the composition of paper for recycling and influences the paper quality. This research project investigated the influence of the multiple recycling of five different corrugated base papers (kraftliner, neutral sulfite semichemical [NSSC] fluting, corrugating medium, testliner 2, and testliner 3) on suspension and strength properties under laboratory conditions. The corrugated board base papers were repulped in a low consistency pulper and processed into Rapid-Köthen laboratory sheets. The sheets were then recycled up to 15 times in the same process. In each cycle, the suspension and the paper properties were recorded. In particular, the focus was on corrugated board-specific parameters, such as short-span compression test, ring crush test, corrugating medium test, and burst. The study results indicate how multiple recycling under laboratory conditions affects fiber and paper properties.

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The role of post-loss anxiety in the development of depressive symptoms and complicated grief symptoms: a longitudinal SEM study

Journal of Affective Disorders ◽

10.1016/j.jad.2020.11.096 ◽

2020 ◽

Author(s):

Bo YAN ◽

Raymond S.K. LO ◽

Amy Y.M. CHOW

Keyword(s):

Depressive Symptoms ◽

Complicated Grief ◽

Sem Study

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Influence of the Aggregate Type on the Properties of Dolomitic Lime-Based Mortars

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.722.343 ◽

2016 ◽

Vol 722 ◽

pp. 343-350 ◽

Cited By ~ 1

Author(s):

Martin Vyšvařil ◽

Tomáš Žižlavský ◽

Patrik Bayer

Keyword(s):

Positive Impact ◽

Total Porosity ◽

Strength Properties ◽

Carbonation Reaction ◽

Dolomitic Lime ◽

Limestone Aggregate ◽

Lime Mortars ◽

Restoration Work ◽

Limestone Fines

Considering the requirement of numerous restoration work on historical buildings with dolomitic lime-based mortars, a research of the applicability and suitability of various types of plasters for repairing the historical plasters have been developed. This work presents the applicability of limestone aggregate and limestone fines to dolomitic lime-based mortars. The role of aggregates on the properties of dolomitic lime mortars was examined by comparing pure quartz sand and limestone aggregate and its quantity in the mortar. Limestone aggregate and limestone fines accelerated the carbonation reaction in the mortars, but the positive impact of limestone aggregates to strength properties of mortars was not observed. Mortars with limestone aggregate showed higher total porosity and water absorption than those with quartz aggregate. Similar results was obtained for mortars with limestone fines. It was found that limestone aggregate and limestone fines, used in this work, is not so suitable and applicable to the dolomitic lime-based mortar as to the aerial lime-based mortars.

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Effects of moisture content, wood species, and form of raw materials on fiber morphology and mechanical properties of wood fiber-HDPE composites

Polymer Composites ◽

10.1002/pc.24336 ◽

2017 ◽

Vol 39 (9) ◽

pp. 3236-3246 ◽

Cited By ~ 4

Author(s):

Xun Gao ◽

Qingde Li ◽

Wanli Cheng ◽

Guangping Han ◽

Lihui Xuan

Keyword(s):

Mechanical Properties ◽

Moisture Content ◽

Wood Species ◽

Raw Materials ◽

Wood Fiber ◽

Fiber Morphology ◽

Morphology And Mechanical Properties

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RESEARCH OF PHYSICAL AND MECHANICAL PROPERTIES OF WOOD-FIBER MATERIALS

chemistry of plant raw material ◽

10.14258/jcprm.2020048150 ◽

2020 ◽

pp. 451-457

Author(s):

Aleksandr Yur'yevich Vititnev ◽

Yuriy Davydovich Alashkevich ◽

Natal'ya Geral'dovna Chistova ◽

Roman Aleksandrovich Marchenko ◽

Venera Nurullovna Matygullina

Keyword(s):

Mechanical Properties ◽

Wood Fiber ◽

Experimental Studies ◽

Physical And Mechanical Properties ◽

Production Method ◽

Strength Properties ◽

Grinding Process ◽

Technological Parameters ◽

Fiber Materials ◽

Traditional Construction

This paper presents the results of experimental studies of the physical and mechanical properties of wood-fiber boards of the wet production method when regulating the design and technological parameters of the grinding process. This allowed us to determine the influence of the working clearance between the grinding discs and the concentration of fibre mass with the subject to of quality change wood fiber after defibrator using the developed construction of the disc fibrillation action on the physico-mechanical properties of boards. As a result of the experiment, regression models were obtained that adequately describe the studied grinding process and allow predicting the values of physical and mechanical properties of the finished product depending on the established parameters process. A comparative analysis of the size and quality characteristics of the fiber semi-finished product and its fractional composition when using a developed construction the disc of refiner fibrillation action and a traditional design used in industry is carried out. The preferential efficiency of the grinding process under the fibrillating effect the disc of refiner in comparison with the traditional construction disc of refiner is established. As a result, there is a significant improvement in the quality indicators of the fiber semi-finished product and its composition due to the formation and predominance in the total mass of long and thin, respectively, flexible fibrillated fibers with high tile-forming properties, which allows to increase the strength properties of the product (by 20–25%), without using binding resins.

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The role of organic matter in formation of the properties of a shale deposit

Доклады Академии наук ◽

10.31857/s0869-56524842220-223 ◽

2019 ◽

Vol 484 (2) ◽

pp. 220-223

Author(s):

И. Ф. Юсупова

Keyword(s):

Organic Matter ◽

Carbonate Rocks ◽

Strength Properties ◽

Low Density ◽

Lower Strength ◽

Reduction Processes ◽

Local Areas ◽

Oil Shales ◽

Mosaic Distribution

Baltic oil shales — kukersites were studied as an example of rocks with rock-forming organic matter (OM). The volumetric significance of their OM is shown (due to the low density) in the volume and thickness of the shale layers. A higher OM content is responsible for a lower strength of the shales relative to the carbonate rocks of the deposit. The variable OM contents and other heterogeneities of the shale layers (structure, nodules, etc.) are factors of the mosaic distribution of areas with different density–strength properties and, as a result, of uneven reduction of layers and their deformation in the case of OM loss (full or partial). It is concluded that the intercalation of kukersite and limestone layers leads to density and strength anisotropy of the shale deposit. Episodic loss of OM and carbonates by the shales is considered for the local areas of the deposit: here, kukersites contain only a terrigenous component with clasts of limestones, shales, and epigenetic sulfides. The loss of OM is explained by sulfate-reduction processes in the underground hydrosphere.

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