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Cellulose nanocrystals (CNC) prepared from eucalyptus cellulose CNCs were modified by the reaction with methyl adipoyl chloride, CNCm, or with a mixture of acetic and sulfuric acid, CNCa. The CNC were either dispersed at 0.1 wt% in the pure solvents ethyl acetate (EA), tetrahydrofuran (THF) and dimethylformamide (DMF) or in cellulose acetate butyrate (CAB) solutions prepared in these solvents at 0...
The aim of the study was to analyze the potential application of cellulose/polyaniline (Ce/Pn) nanocomposite for the treatment of synthetic reactive dye bath effluent. The Ce/Pn composite was synthesized by chemical oxidative polymerization of aniline. A central composite experimental design, a most popular design of response surface methodology, was applied to optimize the level of variables, namely,...
A series of thermoresponsive sodium alginate-g-poly(vinyl caprolactam) (NaAlg-g-PNVCL) beads were prepared as drug delivery matrices of 5-flurouracil (5-FU) crosslinked by glutaraldehyde (GA) in the hydrochloric acid catalyst. Graft copolymers of sodium alginate with vinyl caprolactam were synthesized using azobisisobutyronitrile as an initiator, and characterized by Fourier infrared spectroscopy,...
Films with different numbers of layers have been built by alternating the adsorption of carboxymethyl cellulose (CMC) and chitosan (CHI) at different pH levels. The adsorption process was recorded by quartz crystal microbalance (QCM). The results showed that under all pH conditions considered, the growth of the films is nonlinear. The film construction performed at pH 4.0 (preferred assembly pH) with...
A method to produce predefined patterns in solid iridescent films of cellulose nanocrystals (CNCs) by differential heating of aqueous CNC suspensions during film casting has been discovered. Placing materials of different temperatures beneath an evaporating CNC suspension results in watermark-like patterns of different reflection wavelength incorporated within the final film structure. The patterned...
Composites made of inorganic filler particles and cellulose nanofibres can be applied as substrates for printed electronics. We have studied the structural properties of these substrates both experimentally and with particle-level modeling approach. Our model describes the skeleton structure formed by pigment particles of varied shapes and size distributions. Nanocellulose is assumed to fill voids...
A simple, solvent-free and low cost method to activate the surface of nanofibrillated cellulose films for further functionalization is presented. The method is based on the oxidative properties of UV radiation and ozone, to effectively remove contaminants from nanocellulosic surface, which remains clean and reactive for at least a week. The efficiency of the method is demonstrated by X-ray photoelectron...
In this study, environmentally friendly regenerated cellulose films with enhanced tensile strength were successfully prepared by incorporation of plasticizer agents using 1-ethyl-3-methylimidazolium acetate as solvent. The results of morphology from scanning electron microscopy and atomic force microscopy showed that cellulose films possessed homogeneously, and exhibited smooth structure. 13C CP/MAS...
We studied the stability of molecular sheets with four cellotetraoses in an aqueous environment by molecular dynamics simulation to identify the molecular details of first structure as one of the possibilities in the course of crystallization of cellulose I. After simulation, the molecular sheets formed by van der Waals forces along the (11̄0) and (110) crystal plane did not change their structures...
Fourteen cotton samples of various strength, maturity and fineness were compressed in the same conditions at elevated pressure (2.0 GPa) and temperature (120 °C) in a home-made Bridgman anvil press designed to process samples of about 20 mm diameter. The influence of cotton properties to the abilities to be compacted into a solid 3D object was studied by mechanical measurements (nano-indentation and...
The production of cellulosic man made fibres by the viscose process has been known for more than 120 years now, but still some aspects are not sufficiently understood in detail. The carbohydrates in the pulp are exposed to varying conditions during the manufacturing process. In the first production step of steeping, the strong alkaline treatment leads to undesirable loss reactions of the cellulose...
Nanocrystalline zinc oxide particles were synthesized and simultaneously incorporated into a three-dimensional nanofibrous matrix of bacterial cellulose (BC) pellicles by a newly created method called “ultrasonic-assisted in situ synthesis”. The BC pellicles were first immersed in a zinc acetate solution. Then the Zn2+-absorbed BC pellicle was further immersed in ammonium hydroxide solution with simultaneous...
Development of advanced functional materials from naturally abundant polymers such as cellulose are of significant importance. Of particular interest is embedding antibacterial functionality to cellulose materials to make permanent antibacterial materials and devices. In the present research, a “clickable” quaternary ammonium compound, N-(2-ethoxy-2-oxoethyl)-N,N-dimethylprop-2yn-1-aminium bromide...
The combined effect of enzymatic treatment (biobeating) and NFC addition on the mechanical and physical properties of a papermaking pulp suspension was investigated. The influence of pH, consistency of pulp and reaction time of the enzyme on the pulp strength was evaluated by measuring the breaking length of paper sheets made thereof. The results showed that the enzymatic treatment improved mechanical...
The hybrid inorganic/organic nanopapers based on bacterial cellulose and different type of sol–gel synthesized nanoparticles are fabricated. A simple, rapid, low-cost pathway based on a diffusion step of sol–gel nanoparticles into swollen bacterial cellulose membrane via orbital incubator is developed. This alternative pathway allows to keeping intact the 3D network of the bacterial cellulose membrane...
A novel cellulose-based polyampholyte derivative, carboxylethyl quaternized cellulose (CEQC), was homogeneously synthesized by introducing positively charged quaternary ammonium groups and negatively charged carboxyl groups to the backbone of cellulose. The structure and dilute solution properties of CEQCs were characterized with elemental analysis, FTIR, NMR, viscometer, light scattering and zeta-potential...
The elasticity of the polyacrylamide (PAAm)-kappa carrageenan (κC) composite was determined as a function of (w/v-%) κC content at 40 °C. The gel composites studied contained various percentages (w/v-%) of κC. The elasticity of the swollen PAAm-κC composite was characterized by using the tensile testing technique. This study investigated the elasticity and the percolation threshold of PAAm-κC composite...
Dynamic rheological behaviors of α-cellulose 1-ethyl-3-methylimidazolium acetate ([Emim]Ac) solutions were investigated in a large range of concentrations (0.1–10 wt %) at 25 °C. On the basis of data from the dynamic viscoelastic test, the exponents of the specific viscosity ηsp versus concentration c were determined as 1.0, 2.0 and 4.7 for dilute, semidilute unentangled and entangled regimes respectively,...
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 every measured system...
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 included between the cellulose...
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