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´Consumer Connection’ Fuels NorthShore’s Growth, Paper360º May/June 2020
´Consumer Connection’ Fuels NorthShore’s Growth, Paper360º May/June 2020´Consumer Connection’ Fuels NorthShore’s Growth, Paper360º May/June 2020
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Long-Term or Short-Term Results?, Paper360º May/June 2020
Long-Term or Short-Term Results?, Paper360º May/June 2020
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Over the Wire, Paper360º November/December 2020
Over the Wire, Paper360º November/December 2020
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Communicate, Collaborate: Steve Voorhees on Impactful Leadership, Paper360º November/December 2020
Communicate, Collaborate: Steve Voorhees on Impactful Leadership, Paper360º November/December 2020
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China Bracing for OCC, Plastics Ban, Paper360º November/December 2020
China Bracing for OCC, Plastics Ban, Paper360º November/December 2020
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Improving paper wet strength via increased lignin content and hot-pressing temperature, TAPPI JOURNAL October 2020
ABSTRACT: It is known that the strength properties of wood-based paper materials can be enhanced via hot-pressing techniques. Today, there is a desire not only for a change from fossil-based packaging materials to new sustainable bio-based materials, but also for more effective and eco-friendly solutions for improving the dry and wet strength of paper and board. Against this background, hot pressing of paper made from high yield pulp (HYP), rich in lignin, becomes highly interesting. This study investigated the influence of pressing temperature and native lignin content on the properties of paper produced by means of hot pressing. Kraft pulps of varied lignin content (kappa numbers: 25, 50, 80) were produced at pilot scale from the same batch by varying the cooking time. We then studied the effect of lignin content by evaluating the physical properties of Rapid Köthen sheets after hot pressing in the temperature range of 20°C•200°C with a constant nip pressure of 7 MPa. The pilot-scale cooked pulps were compared with reference samples of mill-produced northern bleached soft-wood kraft (NBSK) pulp and mill-produced chemithermomechanical pulp (CTMP).Generally, the results demonstrated that lignin content had a significant effect on both dry and wet tensile index. All of the pilot cooked pulps with increased lignin content had a higher tensile index than the reference NBSK pulp. To obtain high tensile index, both dry and wet, the pressing temperature should be set high, preferably at least 200°C; that is, well above the glass transition temperature (Tg) for lignin. Moreover, the lignin content should prefera-bly also be high. All kraft pulps investigated in this study showed a linear relationship between wet strength and lignin content.