Cellulose

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

List of Papers (Total 152)

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 ...

Dynamic vapor sorption and thermoporometry to probe water in celluloses

Dynamic vapor sorption and thermoporometry probe complementary dimensions of water interaction with cellulose. While sorption is primarily sensitive to the first hydration layers, thermoporometry is primarily sensitive to the nanometric water-filled pores. In this article, these analytical techniques are detailed and applied to model mesoporous materials and to a wide spectrum of ...

Kinetics of enzymatic deacetylation of chitosan

The current paper reports on an investigation of the kinetics of chitosan deacetylation by chitin deacetylase isolated from Absidia orchidis vel coerulea. The reaction rate was correlated with the concentration of GlcNHAc units of the polymer. It is shown that the process follows the Michaelis–Menten mechanism. Modification of the Michaelis–Menten equation by introducing the ...

Functionalization of cotton with poly-NiPAAm/chitosan microgel. Part I. Stimuli-responsive moisture management properties

Stimuli-responsive microgel, based on synthetic polymer (poly-NiPAAm) and biopolymer (chitosan), was incorporated onto cotton fabric surface by pad-dry-cure method using 1,2,3,4-butanetetracarboxylic acid (BTCA) as crosslinker. In order to assess the moisture management properties of cotton functionalized with responsive microgel, the effects of temperature, relative humidity and ...

Conversion of cellulose Iα to Iβ via a high temperature intermediate (I-HT) and other cellulose phase transformations

The observation that the hydrothermal conversion of cellulose Iα to cellulose Iβ is irreversible has been assumed to be due to the relative free energy of these polymorph phases. We propose an alternative explanation: when cooling the high temperature phase, the barrier to forming Iβ is much smaller than the barrier to forming Iα, so kinetics favor the formation of Iβ. This ...

Functionalization of cotton with poly-NiPAAm/chitosan microgel: Part II. Stimuli-responsive liquid management properties

An innovative strategy for functional finishing of cotton involves application of stimuli-responsive surface modifying system based on temperature- and pH-responsive poly-NiPAAm/chitosan microgel. The stimuli-responsiveness implied to cotton is the consequence of swelling/collapse of the microgel particles incorporated to the fibre surface, which produces an active liquid ...

Cellulose nanofibrils as filler for adhesives: effect on specific fracture energy of solid wood-adhesive bonds

Cellulose nanofibrils were prepared by mechanical fibrillation of never-dried beech pulp and bacterial cellulose. To facilitate the separation of individual fibrils, one part of the wood pulp was surface-carboxylated by a catalytic oxidation using (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) as a catalyst. After fibrillation by a high pressure homogenizer, the obtained aqueous ...

Ligament-like tough double-network hydrogel based on bacterial cellulose

Using the double-network (DN) method, bacterial cellulose/polyacrylamide (BC/PAAm) DN gels able to sustain not only high elongation but also high compression have been synthesized by combining BC gel as the first network with PAAm as the second network in the presence of N,N′-methylene bisacrylamide (MBAA) as a cross-linker. This DN gel was obtained by modifying the monomer ...

The implication of chemical extraction treatments on the cell wall nanostructure of softwood

Spruce wood was subjected to well-defined extraction treatments with sodium chlorite (NaClO2) for delignification, as well as with sodium hydroxide (NaOH) at different concentrations for extraction of hemicelluloses. The corresponding changes of the macromolecular polymer assembly were investigated by small-angle X-ray scattering (SAXS). Measurements with Fourier-transform infrared ...

Analysis of the effects of catalytic bleaching on cotton

Hydrogen peroxide can be catalyzed to bleach cotton fibers at temperatures as low as 30°C by incorporating dinuclear tri-μ-oxo bridged manganese(IV) complex of the ligand 1,4,7-trimethyl-1,4,7-triazacyclononane (MnTACN) as the catalyst in the bleaching solution. The catalytic system was found to be more selective under the conditions applied than the non-catalytic H2O2 system, ...