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Formable papers can be used as an alternative to rigid plastics for making 3D shapes for packaging applications. However, commercial use of formable paper is currently limited, due to its poor extensibility. Cellulosic fibres can be combined with polyurethanes to improve the deformability of resulting fibre-polymer composites. This work describes the effect of spray and wet-end addition of polyurethane dispersions to paper to enhance the extensibility and formability of paper. The increase in extensibility was directly proportional to the amount of polyurethane retained in the paper. Absolute improvements in extensibility were as high as 4 to 6 percentage points. Improved extensibility resulted in better formability of paper, which eventually could allow it to compete with plastic packaging in certain applications. [ABSTRACT FROM AUTHOR]

Production of paper-based packaging is growing at the present moment and has great future prospects. However, the development of new packaging concepts is creating a demand for an improvement in the mechanical properties of paper. Extensibility is one of these properties. Highly extensible papers have the potential to replace certain kinds of plastics used in packaging. Extensibility is also important for the sack and bag paper grades and for runnability in any converting process. This paper reviews the factors that affect the extensibility of fibres and paper, and discusses opportunities for improving the straining potential of paper and paper-like fibre networks. It is possible to classify factors that affect extensibility into three main categories: fibre structure, interfibre bonding, and structure of the fibre network. Extensibility is also affected by the straining situation and the phase state of the polymers in the cell wall. By understanding the basic phenomena related to the elongation, and by combining different methods affecting the deformability of fibre network, extensibility of paper can be raised to a higher level. [ABSTRACT FROM AUTHOR]

Elongation at failure is an important but underrated functional property of paper. Traditionally, elongation has been of specific importance for sack and bag paper grades. Mechanical treatments at high consistency are known to induce fibre deformations that contribute to the elongation of paper. However, it is not clear to what extent different fibre deformations can improve the elongation of paper. The aim of this work was to investigate the influence of three mechanical treatments on fibre and paper properties. The wing defibrator, the E-compactor, and the Valley beater were used for treating chemical softwood pulp. It was found that the type and intensity of mechanical treatments significantly affect the formation of fibre deformations, and thus the resulting properties of paper. The combination of high-consistency wing defibrator treatment and subsequent low-consistency valley beating provided paper with high elongation potential and good strength properties without impairing the dewatering properties. [ABSTRACT FROM AUTHOR]

The primary aim of modern biorefineries is the efficient conversion of lignocellulosic materials into valuable products. Sugars and oils can be converted into valuable chemicals, but processing of lignin is still a challenge. A vast amount of lignin is incinerated to produce process steam and energy, and only a very small part is used for the production of value-added products. Technical lignins are isolated as by-streams in lignocellulosic refineries, e.g., as kraft, soda, organosolv, and hydrolysis lignins, as well as lignosulphonates. They have a modified structure and contain impurities that are dependent on the processing method. The structure and the composition of technical lignins restrict their subsequent applications. This paper reviews limiting factors in utilization of technical lignins. Four major classes of problems are identified, and approaches to overcoming these problems are suggested. [ABSTRACT FROM AUTHOR]

• Cellulose-based solutions can improve environmental performance of food packaging. • Food products require specific barrier functions from cellulose-based packaging. • Eco-design enables quantifying environmental performance and identifying trade-offs. • Fulfilling the barrier requirements for food product packaging is crucial. This short communication describes the climate change impacts of using cellulose, and more precisely cellulosic fiber-based materials, in food packaging, representing current and emerging industrial state of the art technology, without specific reference to current scientific advances. First, the different types of cellulosic fiber-based packaging materials, which can be used to replace fossil-based packaging materials, are presented for flexible and rigid applications. The focus is on technological solutions with packaging properties that enable the protection of commonly sold food products. The manufacturing processes associated with these cellulosic fiber-based materials is described and the environmental impact assessment of 4 selected case studies presented: stand-up pouches, flexible flow wraps, frozen or chilled food trays, and molded pulp lids. A simplified eco-design Life Cycle Assessment (LCA) was then performed to compare each solution with its fossil-based counterpart. Differences and similarities between the various cellulosic solutions have been identified. Furthermore, the assessment confirms that cellulosic fiber-based materials have reduced environmental impacts as compared to fossil-based counterparts, if a similar packaging weight is obtained. Indeed, all impacts of plastics are between 3 and 5 kg CO 2 eq/kg, while all impacts of cellulosic fiber-based materials are below 1.5 kg CO 2 eq/kg. [ABSTRACT FROM AUTHOR]