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Bayesian inference was used to test the powdered cellulose pyrolysis, under the isothermal experimental conditions. A completely new procedure that was based on obtaining the reliable distribution functions of the effective (apparent) activation energy (Ea) values by the statistical derivation of prior and posterior functions was introduced. It has been found that the pyrolysis of the powdered...
In this present work, amino-functionalized nanocrystalline cellulose (ANCC) was prepared by a process involving, (1) extraction of nanocrystalline cellulose (NCC) from fully bleached hardwood kraft pulp by sulfuric acid hydrolysis, (2) sodium periodate oxidation of NCC to yield the corresponding C-2/C-3 dialdehyde nanocellulose (DANC) and (3) grafting with ethylenediamine to obtain ANCC through a...
The carbohydrate-binding modules (CBMs) have emerged as an interesting alternative to enzymes for fibers modification, e.g. of pulp and paper. Glycosylation in CBMs is thought to have a key role in the improvement of cellulose fibers. Thus, in this work the non-glycosylated (CBM3mt) and glycosylated (CBM3wt) recombinant versions of CBM3 from Clostridium thermocellum CipA—both produced in Pichia pastoris...
A novel method has been developed for the rapid determination of the alpha-cellulose content in dissolving pulps. After alkaline treatment of the sample, the alkaline-soluble portion of the filtrate was transformed into colloids in a medium containing ethanol (80 %). The colloid solution was then measured by visible spectroscopy. The results showed a linear correlation between the root of absorbance...
Alpha-cellulose is a part of the wooden material that preserves isotopic composition during tree-growth, and therefore provides important indirect data for paleoclimatological studies. For this reason, it is exceptionally important to extract the alpha-cellulose component from plants, e.g. from tree rings of wood. Since the cell wall of plant cells consists of multicomponent polysaccharides, the extraction...
The aim of this study was to regenerate fibres from the alkaline cellulose solution containing 3-allyloxy-2-hydroxypropyl substituents. Enzyme-treated cellulose was modified in alkaline aqueous tert-butanol (tBuOH) using allyl glycidyl ether (AGE) as the modification reagent. 3-allyloxy-2-hydroxypropyl substituted (AHP) enzyme-treated cellulose with DSA 0.05 was obtained. Enzyme-treated cellulose...
Self-doped polyaniline/cellulose fibers (SPANI/CF) hybrid was in situ prepared by copolymerization of aniline and metanilic acid in presence of cellulose fibers to improve its dedoping-resistant ability. The results indicated that the SPANI/CF hybrid was remarkably more resistant to dedoping by alkaline aqueous solution than the polyaniline/cellulose fibers (PANI/CF) hybrid. Self-doping did not increase...
Cellulose nanocrystals (CNCs) were used to improve the performance of poly(vinylidene fluoride) (PVDF), and the composite properties were characterized. The results showed that the prepared nanocomposites displayed the increases in mechanical properties. In particular, with the incorporation of 6 wt% CNCs, increases in tensile strength and dynamic storage modulus were observed. For hydrophilicity,...
This study was to determine the effect of fiber hornification on the viscosity decrease of prehydrolysis kraft-based dissolving pulp using a commercial endoglucanase-rich cellulase. Three pulp samples, namely never-dried (ND), air-dried (AD) and oven-dried (OD), were used. The results showed that the enzymatic performance in the viscosity decrease was affected by the fiber history: the ND sample showed...
Cotton fabrics have been treated with two different finishing compositions based on urea (U) and ammonium dihydrogen phosphate (AP) in order to enhance their flame retardancy properties, particularly referring to the resistance to a flame application (namely, Limiting Oxygen Index tests) and to an irradiative heat flux of 35 kW/m2 (by cone calorimetry). The collected results have proven a remarkable...
The transient entanglement networks of cellulosic polysaccharides in concentrated solutions were characterized by the molecular weight between entanglements (Me) using dynamic viscoelasticity measurements. From the concentration dependence of Me, Me for the cellulosic polysaccharides in the molten state (Me,melt) was estimated as the material constant reflecting the chain characteristics. The...
Hydroxypropyl methylcellulose and ethyl hydroxyethyl cellulose could be interesting candidates for production of lightweight, foamed packaging material originating from non-fossil, renewable resources. The foaming ability of nine different grades of the two cellulose derivatives, using water as the blowing agent, was investigated using a hot-mold process. The foaming process was studied by evaluating...
A new, industrially feasible method for conferring cellulosic substrates antioxidant properties by using enzymatic products was developed. The method allows cellulose surfaces such as those of paper sheets to be conferred antioxidant capacity by using a functionalization solution (FS) obtained from an enzymatic reaction. Various laccases and different phenolic compounds (PhCs) potentially possessing...
The interaction of copper ions with chitosan and three synthesized derivatives with different chelating centers, N-benzylidene chitosan, N-benzyl chitosan and poly-N-(4-(4-R-methoxyphenyl)diazenyl)-benzyl-chitosan using CuSO4·5H2O and CuCl2·2H2O salts was studied. The content of Cu2+ in the complexes was determined by atomic absorption spectrometry and the results showed that chitosan exhibited higher...
Commercial interests have been escalating worldwide on cellulase enzymes, since it has enormous potentiality to process most abundant and eco-friendly celluloses and convert them into the renewable and sustainable energy, chemicals, fuels and materials. However, overcoming the cellulose recalcitrance and understanding accurate cellulase catalytic activities have been remaining as major technological...
The fact that cellulose materials soften with water uptake is exploited constantly during paper production to form strong bonds between two fibers. Here, we present measurements of surface hardness and reduced modulus of viscose fibers by atomic force microscopy based nanoindentation at varying relative humidity. A home-built setup allowed to access a wide humidity range from 5 % until 95 % relative...
Cellulosic material is chemically modified to impart crease-resistant properties to textile products. Due to health considerations formaldehyde-free chemicals are preferred. For this purpose, (3-glycidyloxy)propyltrimethoxysilane (GPTMS) in combination with metal alkoxides aluminium isopropoxide (AIP), titanium tetraisopropoxide (TTP), zircon tetrabutoxide (ZTB) were applied to cotton raw material...
The low-temperature dissolution mechanism of chitin in NaOH/urea aqueous solution has not been well established yet, especially at a temperature that lowers the crystallization temperature of both NaOH and urea. Using multiple nuclei (1H, 15N and 23Na) nuclear magnetic resonance (NMR) methods, we find that the ternary NaOH/urea/D2O system, different from the fully frozen binary NaOH–D2O system, exhibits...
We previously offered miscibility maps for blend systems of cellulose esters (CEs) including cellulose acetate (CA), propionate (CP), and butyrate (CB) with vinyl copolymers containing an N-vinyl pyrrolidone (VP) unit, i.e., poly(N-vinyl pyrrolidone-co-vinyl acetate) [P(VP-co-VAc)] and poly(N-vinyl pyrrolidone-co-methyl methacrylate) [P(VP-co-MMA)]; the maps were constructed based on data of thermal...
In response to the shortage of petroleum resources and the growing need for sustainable development, cellulose-based amphiphilic copolymers have emerged as a new generation of value-added functional nanostructures from biomass resources. In this article, 17 amphiphilic hydroxyethyl cellulose-based graft copolymers with different side chains, including poly(lactide), poly(ε-caprolactone) and poly(p...
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