Cellulose

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

List of Papers (Total 140)

Isolation and handedness of helical coiled cellulosic thickenings from plant petiole tracheary elements

Leaf stalks (petioles) are critical components of the vascular system that conducts water from the roots to the photosynthetic apparatus of most green plants. Helical coiled cellulosic microfibrils that reinforce the tracheary elements in plant leaf petioles were isolated by a gentle treatment with alkali and acid chlorite from celery and from a number of tree species, including ...

Effects of NO2 and acetic acid on the stability of historic paper

This research investigates degradation of historic paper in polluted environments during long-term dark storage. In an innovative experiment, degradation rates at realistic pollution levels are compared with degradation rates in the absence of pollution, using a set of real historic papers. The most abundant pollutants in repositories in post-industrial environments are taken into ...

Topochemical acetylation of cellulose nanopaper structures for biocomposites: mechanisms for reduced water vapour sorption

Moisture sorption decreases dimensional stability and mechanical properties of polymer matrix biocomposites based on plant fibers. Cellulose nanofiber reinforcement may offer advantages in this respect. Here, wood-based nanofibrillated cellulose (NFC) and bacterial cellulose (BC) nanopaper structures, with different specific surface area (SSA), ranging from 0.03 to 173.3 m2/g, were ...

Stability of manganese dioxide by guar gum in the absence or presence of surfactants

Stability of the manganese dioxide (MnO2) suspensions by non-ionic guar gum (GG) in the absence or presence of the surfactants: anionic sodium dodecyl sulphate (SDS), cationic hexadecyltrimethylammonium bromide (CTAB) and non-ionic Triton X-100 (t-octylphenoxypolyethoxyethanol) and their equimolar mixtures (SDS/TX-100; CTAB/TX-100) was measured using turbidity. The obtained results ...

Quantum chemical calculations of pristine and modified crystalline cellulose surfaces: benchmarking interactions and adsorption of water and electrolyte

In this study, we investigate the hydration of three different functional groups present on cellulose nanocrystal (CNC) surfaces: hydroxyls, carboxylates and sulphates by means of quantum chemical calculation. The performance of several density functional theory (DFT) functionals in reproducing, against higher level MP2 benchmark calculations, relevant non-covalent CNC interactions ...

Fluorescent cellulose aerogels containing covalently immobilized (ZnS)x(CuInS2)1−x/ZnS (core/shell) quantum dots

Photoluminiscent (PL) cellulose aerogels of variable shape containing homogeneously dispersed and surface-immobilized alloyed (ZnS)x(CuInS2)1−x/ZnS (core/shell) quantum dots (QD) have been obtained by (1) dissolution of hardwood prehydrolysis kraft pulp in the ionic liquid 1-hexyl-3-methyl-1H-imidazolium chloride, (2) addition of a homogenous dispersion of quantum dots in the same ...

A comparison of softwood and birch kraft pulp fibers as raw materials for production of TEMPO-oxidized pulp, MFC and superabsorbent foam

This study compares the suitability of using birch kraft pulp or softwood kraft pulp in the preparation of TEMPO-oxidized pulp, MFC and superabsorbent foam. TEMPO oxidation was performed using five different dosages of primary oxidant. The time of disintegration treatment was varied to study its influence on the properties of the produced MFCs and foams. Both the birch and the ...

Cellulose-based materials as scaffolds for tissue engineering

Two types of cellulose-based materials, 6-carboxycellulose with 2.1 or 6.6 wt% of –COOH groups, were prepared and tested for potential use in tissue engineering. The materials were functionalized with arginine, i.e. an amino acid with a basic side chain, or with chitosan, in order to balance the relatively acid character of oxidized cellulose molecules, and were seeded with ...

Influence of surfactants on the adsorption and elektrokinetic properties of the system: guar gum/manganese dioxide

The adsorption of non-ionic polysaccharide—guar gum (GG) in the presence or absence of the surfactants: anionic SDS, cationic CTAB, nonionic TX-100 and their equimolar mixtures SDS/TX-100, CTAB/TX-100 from the electrolyte solutions (NaCl, CaCl2) on the manganese dioxide surface (MnO2) was studied. The increase of GG adsorption amount in the presence of surfactants was observed in ...

Mechanism of structure formation of microbial cellulose during nascent stage

The structure of microbial cellulose (MC) produced by Acetobacter xylinum was studied in presence of Fluorescent Brightener, Direct Blue 1, 14, 15, 53, Direct Red 28, 75 and 79, as probe. X-ray diffraction pattern of the product showed that it was a crystalline complex of dye and cellulose. The product has the structure in which the monomolecular layer of the dye molecule is ...

Cellulose-TiO2 nanocomposite with enhanced UV–Vis light absorption

TiO2/N-cellulose nanocomposite was successfully prepared in the (cyclohexyl)hexyl-dimethylammonium acetate–dimethyl sulfoxide solution. The obtained composite was characterized with various techniques like UV–Vis/DR, FTIR/DRS, X-ray diffraction, thermogravimetric analysis, DLS method and BET SSA measurements. TiO2/N-cellulose nanocomposite exhibited high UV–Vis light absorption ...

Quantum mechanical modeling of the structures, energetics and spectral properties of Iα and Iβ cellulose

Periodic planewave and molecular cluster density functional theory (DFT) calculations were performed on Iα and Iβ cellulose in four different conformations each. The results are consistent with the previous interpretation of experimental X-ray and neutron diffraction data that both Iα and Iβ cellulose are dominantly found in the tg conformation of the hydroxymethyl group with a ...

Modelling of Congo red adsorption on the hydrophobic surface of cellulose using molecular dynamics

This study describes the interaction between crystalline cellulose and the direct dye Congo red (CR) using molecular dynamics simulations. A model of a microfibril corner of cellulose Iβ, exposing one hydrophobic (1 0 0) and the two hydrophilic (1 1 0) and (1 −1 0) surfaces was built. The energetic and geometric features of the dye adsorption were investigated at different ...

Regioselective cationization of cellulosic materials using an efficient solvent-minimizing spray-technique

Cationization of different cellulosic materials was successfully accomplished using an efficient solvent-minimizing spray-technique. The obtained materials were studied and evaluated in regard to reaction efficiency and regioselectivity using 1D and 1H–13C correlated 2D NMR experiments. The high consistencies and temperatures applied using the spray-technique resulted in reagent ...

New fiber-reactive UV-absorbers increasing protective properties of cellulose fibres

Several new UV-absorbers with built-in monochlorotriazine and vinylsulphone cellulose-reactive residues were synthesised. Their application properties on various cellulose-based textile materials were determined and the UV-protection factor values of modified fabrics were measured.

Cellulose fibers modified by Eu3+-doped yttria-stabilized zirconia nanoparticles

This paper describes a method for manufacturing luminescent cellulose fibers. Good optical properties of cellulose fibers under UV-C illumination were achieved by incorporating ZrO2 (0.5 mol% of Eu3+) stabilized by Y2O3 (7 mol%) into the fiber structure’s particles. Fibers were obtained from 8 wt% cellulose solution in N-methylmorpholine N-oxide (NMMO) with the addition of a ...

Luminescent cellulose fibers activated by Eu3+-doped nanoparticles

UV- active cellulose fibers were obtained by dry-wet method spinning an 8 % by weight α-cellulose solution in N-methylomorpholine-N-oxide (NMMO) modified by europium-doped gadolinium oxyfluoride Gd4O3F6:Eu3+ containing 5 mol (%) of the dopant. Photoluminescent nanoparticles were introduced in the in powder form into a polymer matrix during the process of cellulose dissolution in ...

Reinforced absorbent material: a cellulosic composite of TEMPO-oxidized MFC and CTMP fibres

This research aims to develop new materials based on renewable resources that can fulfill the functions necessary in the absorption core of a disposable diaper. Absorbent foam was recently produced from softwood kraft pulp by TEMPO oxidation, disintegration and freeze drying. In this study, the TEMPO-oxidized MFC was mixed with pulp fibres, thus forming a cellulosic composite, in ...