Prediction of Handsheet Tensile Strength by Computational Simulation of Structure

TAPPI Journal ◽  
2010 ◽  
Vol 9 (1) ◽  
pp. 15-19
Author(s):  
RÉMI VINCENT ◽  
MARTINE RUEFF ◽  
CHRISTIAN VOILLOT
Keyword(s):  
Tensile Strength ◽  
Breaking Strength ◽  
Computational Simulation ◽  
Physical Property ◽  
Size Distributions ◽  
Fiber Morphology ◽  
Paper Properties ◽  
Texture Property ◽  
Paper Structure ◽  
Fiber Breaks

To better understand the influence of fiber morphology on paper properties, we developed a novel 3-D computational simulator of paper structure, which was validated through experimental work. This simulator creates virtual pieces of handsheets using the size distributions of the fibers as the main inputs. Once the structure is generated, physical properties can be assessed. The main principles of the simulation and the results for one global texture property, the apparent density, were presented in a previous paper. In this paper, we focus on the prediction of the tensile breaking strength, the most commonly used physical property for paper characterization. The model is based on the model developed by Shallhorn and Karnis, which was adapted to take into account the fiber morphological distributions. It was successfully applied in the absence of fiber breaks during the test and validated with the 10 pulps used in the first part of the study.

Effect of ionic liquid pretreatment on paper physical property and pulp refining performance

2019 ◽  
Vol 34 (4) ◽  
pp. 495-506
Author(s):  
Mingfu Li ◽  
Douyong Min ◽  
Xing Long ◽  
Qiyuan Tu ◽  
Kelei Zhang ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Photoelectron Spectroscopy ◽  
Fiber Strength ◽  
Chemical Properties ◽  
Physical Property ◽  
Paper Strength ◽  
Fiber Morphology ◽  
Paper Properties ◽  
X Ray ◽  
Refining Performance

Abstract Ionic liquids (IL) of 1-butyl-3-methylimidazolium chloride (BmimCl) homogeneously mixed with bleached kraft pulp (BKP) were used to investigate the change of paper properties and refining performance under the general conditions. Fiber morphology and paper strength were determined by fiber analyzer and paper physical property tester. The surface morphology and chemical properties of fiber was also performed by scanning electron microscope (SEM), X-ray Diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The results indicated the optimized conditions of BmimCl pretreatment were BmimCl dosage of 1.5 mL/g, the time and temperature of 30 min and 80 °C, respectively. The physical properties of paper and internal bond strength of fiber was improved by BmimCl pretreatment. BmimCl pretreatment facilitated swelling and fibrillation of fiber, increased the crystalline index of fiber and decreased the lignin and extractives on the surface of fiber, which leading to improve fiber strength and tensile strength. For the same refining energy input, saving the maximum refining energy consumption was 14.0 % after BmimCl pretreatment, which is beneficial to improve the application of ionic liquid in pulp and papermaking.

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

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.

Tensile properties of finger-jointed lumber under high-temperature and oxygen-free conditions

Holzforschung ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Kong Yue ◽  
Feng Wang ◽  
Weidong Lu ◽  
Zhongqiu Tang ◽  
Zhangjing Chen ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Tensile Properties ◽  
High Temperatures ◽  
Variable Temperature ◽  
Physical Property ◽  
Solid Wood ◽  
Nitrogen Atmosphere ◽  
Thermal Physical Property ◽  
Electron Microscopy Analysis ◽  
Increasing Temperature

Abstract A model for engineered wood was developed that considers the parallel-to-grain tensile strength of finger-jointed lumber at high temperatures relevant to fire conditions. The finger-jointed lumber was composed of Douglas fir, larch, and poplar wood with phenol-resorcinol-formaldehyde (PRF) as an adhesive. The tensile properties of the finger-jointed lumber were evaluated at high temperatures under oxygen-free conditions, i.e. in a nitrogen atmosphere. A combination of chemical and thermal-physical property analysis of the PRF adhesive and microscopic observations on the glueline was used to discuss the reduction of tensile strength of the parallel-to-grain finger-jointed lumber at variable temperature. The results show that the tensile strength of the finger-jointed lumber decreased linearly with increasing temperature. The parallel-to-grain tensile strength of the PRF finger-jointed samples at 20 and 280 °C were 84 and 5% of the tensile strength of the solid wood at 20 °C, respectively. The thermal-physical properties and scanning electron microscopy analysis revealed that the pyrolysis intensity of the PRF adhesive was lower than that of the wood at 220 °C or higher.

Action Mechanism of the Improvement of Printability for Eucalypt Bleached Kraft Pulp Pretreated by Cellulase

2013 ◽  
Vol 779-780 ◽  
pp. 294-301
Author(s):  
Wan You Tang ◽  
Li Chen ◽  
Zheng Jian Zhang
Keyword(s):  
Tensile Strength ◽  
Fiber Length ◽  
Kraft Pulp ◽  
Pulp Fiber ◽  
Fiber Morphology ◽  
Strength Index ◽  
Bleached Kraft Pulp ◽  
Tear Index ◽  
Pulp Sample ◽  
The Mean

Enzymatic refining of eucalypt bleached kraft pulp with the cellulase NOV476 was studied. The effects of this cellulase on the physical properties of pulp, fiber morphology and fiber appearance of the eucalypt bleached kraft pulp in different application conditions were discussed. The results show that, with the increase in the amount of enzyme, tensile strength index, burst index and TEA index of paper are increased and then decreased; elongation and tear index of paper have been declining, Zeeil tensile strength index has been an upward trend. Without beating the pulp sample, gradually increases as the amount of enzyme, the average fiber length and the average fiber width are gradually reduced, while mean kink index substantially constant. Number of vessels in fiber overall reduced tendency reaches a minimum in the amount of enzyme 0.5μ/g, the phenomenon is most obvious. In the same conditions of beating time, gradually increases as the amount of enzyme, the average fiber length is gradually reduced, an average fiber width is gradually increased, the mean kink index reaches a maximum in the amount of enzyme is 0.5μ/g. Number of vessels in fiber overall reduced trend.

The Inter-Relationship Between Paper Structure and Print Quality in Ink Jet Printing

1990 ◽  
Vol 197 ◽  
Author(s):  
John F. Oliver ◽  
A. Y. Jones
Keyword(s):  
Quality Evaluation ◽  
Capillary Absorption ◽  
Print Quality ◽  
Paper Properties ◽  
Coated Papers ◽  
Ink Jet ◽  
The Future ◽  
Jet Printing ◽  
Paper Structure ◽  
Potential Opportunity

ABSTRACTThis article describes a print quality evaluation of laboratory designed ink jet papers prepared on a dynamic former. A comparison with various plain and coated papers serves to illustrate the potential opportunity for papermakers to exploit novel types of paper structures in the future. The article will also briefly focus on some of the fundamental issues and key paper properties which perturb print quality and govern the capillary absorption of aqueous inks.

Spark Plasma Sintering of Mechanically Activated Ni and Al Powders

2014 ◽  
Vol 1040 ◽  
pp. 772-777 ◽  
Author(s):  
Lilia I. Shevtsova ◽  
Michail A. Korchagin ◽  
Alexander Thömmes ◽  
Vyacheslav I. Mali ◽  
Alexander G. Anisimov ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Spark Plasma Sintering ◽  
Temperature Synthesis ◽  
Plasma Sintering ◽  
High Temperature Synthesis ◽  
Ni Powder ◽  
Spark Plasma ◽  
Paper Structure ◽  
Sintered Materials

In this paper structure and mechanical properties of Ni3Al intermetallic compound was studied. The materials was fabricated according to different schemes, which combined mechanical alloying of Ni and Al powders, self-propagating high temperature synthesis (SHS) and spark plasma sintering (SPS). Relative density of all sintered samples was ~ 97 %. Microhardness of the sintered materials ranged from 6100 to 6300 MPa. SPS of 86.71 % wt. Ni and 13.29 % wt. Ni powder at 1100 °C led to formation of material with the highest level of tensile strength equal to 400 MPa.

scholarly journals Computational Simulation Tools to Support the Tissue Paper Furnish Management: Case Studies for the Optimization of Micro/Nano Cellulose Fibers and Polymer-Based Additives

Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3982
Author(s):  
Flávia P. Morais ◽  
Ana M. M. S. Carta ◽  
Maria E. Amaral ◽  
Joana M. R. Curto
Keyword(s):  
Case Studies ◽  
Raw Materials ◽  
Computational Simulation ◽  
Cellulose Fibers ◽  
Paper Properties ◽  
Fiber Modification ◽  
Simulation Tools ◽  
Tissue Paper ◽  
Nano Cellulose ◽  
End Use

Tissue paper production frequently combines two main types of raw materials: cellulose fibers from renewable sources and polymer-based additives. The development of premium products with improved properties and functionalities depends on the optimization of both. This work focused on the combination of innovative experimental and computational strategies to optimize furnish. The main goal was to improve the functional properties of the most suitable raw materials for tissue materials and develop new differentiating products with innovative features. The experimental plan included as inputs different fiber mixtures, micro/nano fibrillated cellulose, and biopolymer additives, and enzymatic and mechanical process operations. We present an innovative tissue paper simulator, the SimTissue, that we have developed, to establish the correlations between the tissue paper process inputs and the end-use paper properties. Case studies with industrial interest are presented in which the tissue simulator was used to design tissue paper materials with different fiber mixtures, fiber modification treatments, micro/nano fibrillated cellulose, and biopolymer formulations, and to estimate tissue softness, strength, and absorption properties. The SimTissue was able to predict and optimize a broader range of formulations containing micro/nanocellulose fibers, biopolymer additives, and treated-fiber mixtures, saving laboratory and industrial resources.

Effect of machine speed on formation and strength efficiency in twin-wire roll forming of never-dried unbleached softwood kraft pulp

2018 ◽  
Vol 33 (2) ◽  
pp. 271-278
Author(s):  
Bengt Nordström ◽  
Lennart Hermansson
Keyword(s):  
Tensile Strength ◽  
Kraft Pulp ◽  
Roll Forming ◽  
Favorable Effect ◽  
Paper Properties ◽  
Difference Curve ◽  
Insignificant Effect ◽  
Wide Range ◽  
Softwood Kraft Pulp ◽  
Machine Speed

Abstract There is a constant drive to increase machine speed in the production of kraftliner and most other major paper grades, but the separate effect of the machine speed on the paper properties has been unclear. The effect of machine speed in twin-wire roll forming of never-dried unbleached softwood kraft pulp was evaluated here in a pilot machine investigation by examining three machine speed levels (500, 750, and 1000 m/min) over a series of jet-to-wire speed differences. Similar headbox consistency and draw from wire section to winding were employed at the different machine speed levels. An increase in the machine speed had a favorable effect on formation and Z-strength efficiency over a wide range of jet-to-wire speed differences, whereas the machine speed had an insignificant effect on tensile strength efficiency and tensile stiffness efficiency. For all properties, the overall shape of the jet-to-wire speed difference curve remained similar when changing the machine speed.

Study on the failure of guide ropes used in mines

2021 ◽  
Vol 63 (6) ◽  
pp. 357-361
Author(s):  
M K Singh ◽  
M Mallick ◽  
M K Verma
Keyword(s):  
Tensile Strength ◽  
Physical Examination ◽  
Breaking Strength ◽  
Substantial Reduction ◽  
Breaking Load ◽  
Strength Measurement ◽  
Wear And Corrosion ◽  
Cause Of Failure ◽  
Loss Of Strength ◽  
Causes Of Failure

The skips/cages in mine hoisting have to be guided to achieve high hoisting rates. Steel guide ropes are used in hoisting because they can safely guide the skips/cages and have been observed to be economical. Guide ropes are static in nature and are thus more prone to corrosion. An investigation into the causes of failure of a guide rope is discussed in this paper. The study consists of physical examination, examination of wear and corrosion, macro- and micro-examination, examination of the breaking load and individual tensile strength measurement of the rod. The main cause of failure is found to be corrosion. Heavy abrasion and corrosion together causes a substantial reduction in diameter of more than 60%. Corrosion raises the stress level and thereby weakens the grains, which is indicated by the cracks that have developed all along the grains as revealed through micro-examination. This affects the breaking strength and reveals a 37% loss of strength, as a result of which failure occurs.

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