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Stiffness and strength properties of five paperboards and their moisture dependency, TAPPI Journal February 2020

ABSTRACT: Five commercial multiply folding boxboards made on the same paperboard machine have been analyzed. The paperboards were from the same product series but had different grammage (235, 255, 270, 315, 340 g/m2) and different bending stiffness. The paperboards are normally used to make packages, and because the bending stiffness and grammage varies, the performance of the packages will differ. Finite element simulations can be used to predict these differences, but for this to occur, the stiffness and strength properties need to be deter-mined. For efficient determination of the three-dimensional properties in the machine direction (MD), cross direction (CD), and Z direction (ZD), it is proposed that the paperboard should be characterized using in-plane tension, ZD-tension, shear strength profiles, and two-point bending. The proposed setups have been used to determine stiff-ness and strength properties at different relative humidity (20,% 50%, 70%, and 90% RH), and the mechanical proper-ties have been evaluated as a function of moisture ratio.There was a linear relation between mechanical properties and moisture ratio for each paperboard. When the data was normalized with respect to the standard climate (50% RH) and plotted as a function of moisture ratio, it was shown that the normalized mechanical properties for all paperboards coincided along one single line and could therefore be expressed as a linear function of moisture ratio and two constants.Consequently, it is possible to obtain the mechanical properties of a paperboard by knowing the structural properties for the preferred level of RH and the mechanical property for the standard climate (50% RH and 23°C).

The Paper360° 2020 TOP 50 POWER LIST, Paper360º July/August 2020

The Paper360° 2020 TOP 50 POWER LIST, Paper360º July/August 2020

Understanding extensibility of paper: Role of fiber elongation and fiber bonding, TAPPI Journal March 2020

ABSTRACT: The tensile tests of individual bleached softwood kraft pulp fibers and sheets, as well as the micro-mechanical simulation of the fiber network, suggest that only a part of the elongation potential of individual fibers is utilized in the elongation of the sheet. The stress-strain curves of two actual individual pulp fibers and one mimicked classic stress-strain behavior of fiber were applied to a micromechanical simulation of random fiber networks. Both the experimental results and the micromechanical simulations indicated that fiber bonding has an important role not only in determining the strength but also the elongation of fiber networks. Additionally, the results indicate that the shape of the stress-strain curve of individual pulp fibers may have a significant influence on the shape of the stress-strain curve of a paper sheet. A large increase in elongation and strength of paper can be reached only by strengthening fiber-fiber bonding, as demonstrated by the experimental handsheets containing starch and cellulose microfibrils and by the micromechanical simulations. The key conclusion related to this investigation was that simulated uniform inter-fiber bond strength does not influence the shape of the stress-strain curve of the fiber network until the bonds fail, whereas the number of bonds has an influence on the activation of the fiber network and on the shape of the whole stress-strain curve.

Closed-Loop Vacuum Control in Papermaking: A Data-Driven Approach to Wet End Optimization, TAPPICon26

New improved quality inspection for food and liquid packaging board - innovative use of 3D detection for inspecting indents and outdents, and UV- technology for reliable inspection of oil, TAPPICon26

Mechanical Pulp with Added Value Products and Lower COD, 2018 IBBC

Mechanical Pulp with Added Value Products and Lower COD, 2018 IBBC

Influence of tensile straining and fibril angle on the stiffness and strength of previously dried kraft pulp fibers, TAPPI JOURNAL July 2018

Influence of tensile straining and fibril angle on the stiffness and strength of previously dried kraft pulp fibers, TAPPI JOURNAL July 2018

Wet-end addition of nanofibrillated cellulose pretreated with cationic starch to achieve paper strength with less refining and higher bulk, TAPPI JOURNAL July 2018

Wet-end addition of nanofibrillated cellulose pretreated with cationic starch to achieve paper strength with less refining and higher bulk, TAPPI JOURNAL July 2018

Factors affecting the free shrinkage of handsheets: apparent density, fines content, water retention value, and grammage, TAPPI JOURNAL June 2018

Factors affecting the free shrinkage of handsheets: apparent density, fines content, water retention value, and grammage, TAPPI JOURNAL June 2018

Using online bubble size and total dissolved solids measurements to investigate the performance of oxygen delignification, TAPPI JOURNAL June 2018

Using online bubble size and total dissolved solids measurements to investigate the performance of oxygen delignification, TAPPI JOURNAL June 2018