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Trondheim, Norway

The Paper and Fibre Research Institute ) is a centre of expertise for wood fibres, pulp and paper, new biobased materials and sustainable biorefining.PFI was established in Kristiania in 1923 as the Norwegian Pulp and Paper Research Institute. PFI moved to Trondheim in 1997/98, and established a close cooperation with the Department of Chemical Engineering at the Norwegian University of Science and Technology. In 2004 PFI changed name to the Paper and Fibre Research Institute and became a subsidiary of Innventia in Stockholm, Sweden. Wikipedia.

During the last decade, major efforts have been made to develop adequate and commercially viable processes for disintegrating cellulose fibres into their structural components. Homogenisation of cellulose fibres has been one of the principal applied procedures. Homogenisation has produced materials which may be inhomogeneous, containing fibres, fibres fragments, fibrillar fines and nanofibrils. The material has been denominated microfibrillated cellulose (MFC). In addition, terms relating to the nano-scale have been given to the MFC material. Several modern and high-tech nano-applications have been envisaged for MFC. However, is MFC a nano-structure? It is concluded that MFC materials may be composed of (1) nanofibrils, (2) fibrillar fines, (3) fibre fragments and (4) fibres. This implies that MFC is not necessarily synonymous with nanofibrils, microfibrils or any other cellulose nano-structure. However, properly produced MFC materials contain nano-structures as a main component, i.e. nanofibrils. © 2011 Chinga-Carrasco. Source

Chinga-Carrasco G.,Paper And Fibre Research Institute
Micron | Year: 2013

In this study, the suitability of optical devices for quantification of the fibrillation degree of bleached microfibrillated cellulose (MFC) materials has been assessed. The techniques for optical assessment include optical scanner, UV-vis spectrophotometry, turbidity, quantification of the fiber fraction and a camera system for dynamic measurements. The results show that the assessed optical devices are most adequate for quantification of the light transmittance of bleached MFC materials. Such quantification yields an estimation of the fibrillation degree. Films made of poorly fibrillated materials are opaque, while films made of highly fibrillated materials containing a major fraction of nanofibrils are translucent, with light transmittance larger than 90%. Finally, the concept of using images acquired with a CCD camera system, for estimating the fibrillation degree in dynamic conditions was exemplified. Such systems are most interesting as this will widen the applicability of optical methods for quantification of fibrillation degree online in production lines, which is expected to appear in the years to come. © 2013 Elsevier Ltd. Source

Paper And Fibre Research Institute | Date: 2013-09-24

The invention relates to an aqueous coating composition of nano cellulose (e.g., microfibrillated cellulose), characterized in that has a dry matter concentration of 2%-12% of nano cellulose and comprises at least one cationic surfactant, which may be chosen among Hexadecyltrimethyl-ammonium bromide, Octadecyltrimethyl-ammonium bromide, Hexadecylpyridinium chloride and Tetradecyl trimethyl-ammonium bromide, Dodecyl pyridinium chloride. The invention also pertains to use of the composition as a coating layer and as an oxygen barrier layer. Further it relates to substrates, e.g., board, cardboard or paper coated with the composition. Moreover, the invention pertains to a process for preparing the coating composition.

Rodionova G.,Norwegian University of Science and Technology | Lenes M.,Paper And Fibre Research Institute | Eriksen O.,Paper And Fibre Research Institute | Gregersen O.,Norwegian University of Science and Technology
Cellulose | Year: 2011

Heterogeneous acetylation of microfibrillated cellulose (MFC) was carried out to modify its physical properties and at the same time to preserve the morphology of cellulose fibrils. The overall reaction success was assessed by FTIR together with the degree of substitution (DS) defined by titration and the degree of surface substitution (DSS) evaluated by means of XPS. Dynamic contact angle measurements confirmed the hydrophobicity improvement relative to non-modified samples. The increase of contact angle upon reaching a certain reaction time and some decrease following the further acetylation was confirmed. Mechanical properties of MFC films made from chemically modified material were evaluated using tensile strength tests which showed no significant reduction of tensile strength. According to SEM images, dimension analysis and tensile strength data, the acetylation seemed not to affect the morphology of cellulose fibrils. © 2010 Springer Science+Business Media B.V. Source

Chinga-Carrasco G.,Paper And Fibre Research Institute | Syverud K.,Paper And Fibre Research Institute
Journal of Nanoparticle Research | Year: 2010

Films made of nanofibrillated cellulose (NFC) are most interesting for use in packaging applications. However, in order to understand the film-forming capabilities of NFC and their properties, new advanced methods for characterizing the different scales of the structures are necessary. In this study, we perform a comprehensive characterisation of NFC-films, based on desktop scanner analysis, scanning electron microscopy in backscatter electron imaging mode (SEM-BEI), laser profilometry (LP) and field-emission scanning electron microscopy in secondary electron imaging mode (FE-SEM-SEI). Objective quantification is performed for assessing the (i) film thicknesses, (ii) fibril diameters and (iii) fibril orientations, based on computer-assisted electron microscopy. The most frequent fibril diameter is 20-30 nm in diameter. A method for acquiring FESEM images of NFC surfaces without a conductive metallic layer is introduced. Having appropriate characterisation tools, the structural and mechanical properties of the films upon moisture were quantified. Source

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