Cellulose

http://link.springer.com/journal/10570

List of Papers (Total 174)

Bound and free water distribution in wood during water uptake and drying as measured by 1D magnetic resonance imaging

Knowledge on moisture transport in wood is important for understanding its utilization, durability and product quality. Moisture transport processes in wood can be studied by Nuclear Magnetic Resonance (NMR) imaging. By combining NMR imaging with relaxometry, the state of water within wood can be identified, i.e. water bound to the cell wall, and free water in the cell lumen...

Material properties of the cell walls in nanofibrillar cellulose foams from finite element modelling of tomography scans

The mechanical properties of the nanofibrillar cellulose foam depend on the microstructure of the foam and on the constituent solid properties. The latter are hard to extract experimentally due to difficulties in performing the experiments on the micro-scale. The aim of this work is to provide methodology for doing it indirectly using extracted geometry of the microstructure. X...

Grafting of thermosensitive poly(N-isopropylacrylamide) from wet bacterial cellulose sheets to improve its swelling-drying ability

Thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) is grafted from wet bacterial cellulose (WBC) sheets using atom transfer radical polymerization (ATRP). WBC is recognized as a highly swollen biocompatible material with broad application potential. However, native WBC undergoes drying relatively fast and its reswelling ability diminishes after losing a substantial amount of...

Critical evaluation of approaches toward mass deacidification of paper by dispersed particles

Mass deacidification has been an important topic in cellulose science and will continue to be a critical issue as long as acidic books and paper-based materials are—a often major—part of library and archive stocks. Different means are available to judge the result of a deacidification treatment and to address its sustainability and efficacy. The present study compares...

Surface modified cellulose scaffolds for tissue engineering

We report the ability of cellulose to support cells without the use of matrix ligands on the surface of the material, thus creating a two-component system for tissue engineering of cells and materials. Sheets of bacterial cellulose, grown from a culture medium containing Acetobacter organism were chemically modified with glycidyltrimethylammonium chloride or by oxidation with...

Temperature dependence of methanol and the tensile strength of insulation paper: kinetics of the changes of mechanical properties during ageing

This paper reports the temperature-dependence of methanol generation and the tensile index under ageing conditions for two paper/oil systems: one consisting of a standard wood Kraft paper and the other of a thermally-upgraded Kraft paper (TUK). A linear correlation between methanol and the tensile index for these paper/oil systems was observed in a previous study at 170 °C. In...

Investigation on functionalization of cotton and viscose fabrics with AgNWs

A study on the functionalization of cotton and viscose fabrics to achieve bifunctional conductive and antibacterial properties was carried out; 0.5 wt% AgNW ethanolic colloid was prepared, and fabrics were dipped and dried in the colloid 1, 10 and 15 times. After one dipping, both fabrics remained nonconductive, and the surface resistance (R s) of cotton was 4.9 × 1010 and of...

Engineering microfluidic papers: determination of fibre source and paper sheet properties and their influence on capillary-driven fluid flow

In the present study, the surface chemistry of fibres from different sources (groundwood, cotton linters, eucalyptus sulphate and a mixture of pine sulphate and spruce sulphate) was initially assessed via inverse gas chromatography. Significant differences were revealed among the four fibre types, especially between groundwood and the other three with regard to the surface energy...

Surface properties and porosity of highly porous, nanostructured cellulose II particles

Recently, a new member of the nanocellulose family was introduced, a cellulose II gel consisting of nanostructured and spherical particles. In this study, we compared two different drying techniques to obtain highly porous powders from this gel with preserved meso- and macroporous nanostructure: first, freeze-drying after solvent exchange to tBuOH and second, supercritical drying...

Aggregation behavior of aqueous cellulose nanocrystals: the effect of inorganic salts

Natural anisotropic building-blocks such as cellulose nanocrystals (CNCs) have attracted considerable attention due to their biodegradability and nanometer-size. In this work the colloidal behavior of CNCs, obtained from sulfuric acid hydrolysis of microcrystalline cellulose, has been studied in presence of salts of different valences. The influence on the colloidal stability and...

Modeling of negative Poisson’s ratio (auxetic) crystalline cellulose Iβ

Energy minimizations for unstretched and stretched cellulose models using an all-atom empirical force field (molecular mechanics) have been performed to investigate the mechanism for auxetic (negative Poisson’s ratio) response in crystalline cellulose Iβ from kraft cooked Norway spruce. An initial investigation to identify an appropriate force field led to a study of the...

Qualitative evaluation of microfibrillated cellulose using the crill method and some aspects of microscopy

It has been a challenge to develop rapid online characterisation techniques for nanocellulose given the fibrillar structure of the nanoparticles. The crill optical analyser uses optical response signals in the infrared (IR) and ultraviolet (UV) wavelength ranges to evaluate the particle size properties of micro/nanofibrillar cellulosic materials. In this work, the crill analyser...

On the relationship between fibre composition and material properties following periodate oxidation and borohydride reduction of lignocellulosic fibres

Periodate oxidation followed by borohydride reduction was performed on four structurally different pulp fibres to clarify the effect of chemical composition on the structural and mechanical properties of sheets made from these fibres. The main purpose was to explore the possibility of extending the use of lignocellulose fibres in novel applications. The degree of oxidation...

Biopolyols obtained via crude glycerol-based liquefaction of cellulose: their structural, rheological and thermal characterization

In this work lignocellulose biomass liquefaction was used to produce biopolyols suitable for the manufacturing of rigid polyurethane foams. In order to better evaluate the mechanism of the process, pure cellulose was applied as a raw material. The effect of time and temperature on the effectiveness of liquefaction and the parameters of resulting biopolyols were characterized. The...

Spherical nanocomposite particles prepared from mixed cellulose–chitosan solutions

Novel cellulose–chitosan nanocomposite particles with spherical shape were successfully prepared via mixing of aqueous biopolymer solutions in three different ways. Macroparticles with diameters in the millimeter range were produced by dripping cellulose dissolved in cold LiOH/urea into acidic chitosan solutions, inducing instant co-regeneration of the biopolymers. Two types of...

Processing and structure–property relationships of natural rubber/wheat bran biocomposites

In this work, wheat bran was used as cellulosic filler in biocomposites based on natural rubber. The impact of wheat bran content [ranging from 10 to 50 parts per hundred rubber (phr)] on processing, structure, dynamic mechanical properties, thermal properties, physico-mechanical properties and morphology of resulting biocomposites was investigated. For better characterization of...

Per-O-acylation of xylan at room temperature in dimethylsulfoxide/N-methylimidazole

The per-O-acylation of xylan-type hemicellulose was firstly carried out in dimethylsulfoxide/N-methylimidazole (DMSO/NMI) at room temperature without additional catalyst. The optimum conditions for esterification of xylan was investigated in terms of the molar ratio of reagents to anhydroxylose units (AXU) in xylan and the kinds of esterification reagents to obtain a high degree...

Revision of adsorption models of xyloglucan on microcrystalline cellulose

Interactions among cellulose, hemicellulose and pectins are important for plant cell wall assembly and properties and also for industrial applications of these polysaccharides. Therefore, binding of pectin and xyloglucan on microcrystalline cellulose was investigated in this experiment by adsorption isotherms, zeta potential and scanning electron microscopy (SEM). Analysis of...

On the anomalous temperature dependence of cellulose aqueous solubility

The solubility of cellulose in water-based media is promoted by low temperature, which may appear counter-intuitive. An explanation to this phenomenon has been proposed that is based on a temperature-dependent orientation of the hydroxymethyl group. In this paper, this hypothesis is investigated using molecular dynamics computer simulations and NMR spectroscopy, and is discussed...

Morphology and rheology of cellulose nanofibrils derived from mixtures of pulp fibres and papermaking fines

The rheological behaviour of homogenised fibres originally having different lengths was evaluated. For this purpose, mixtures of pulp fibres and fines were fibrillated mechanically without pre-treatment and characterised with regard to morphology and viscosity. It was found that, for all samples, a similar number of homogenisation passes was needed to reach a viscosity plateau...

Initial wet web strength of paper

Despite much research into and development within the complex area of the initial wet web strength of paper, no complete model has yet been developed to describe this property. This type of paper strength is the most important property to ensure an effective paper machine run. Furthermore, the process of strength development in the sheet forming and pressing portion of the...

Fabrication of superhydrophobic cotton fabrics by a simple chemical modification

Hydrophobization of cotton fabrics was carried out with the use of bifunctional polysiloxanes with various contents of functional groups. Polysiloxanes contained in their structure groups capable of bonding to substrates (trialkoxysilyl or glycidyl ones) and fluoroalkyl groups showing surface activity. Two methods of surface modification were compared: (1) a one-step method via...

Application of nanocomposite cellulose fibers with luminescent properties to paper functionalization

Cellulose fibres modified with the luminescent inorganic compound were obtained by using N-methylmorpholine-N-oxide as a direct solvent. The fibres were cut and introduced to the unrefined and refined paper pulp samples. Schopper-Riegler value of the pulps were measured and the laboratory paper samples were formed. Observations under UV radiation showed that the cellulose...