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In secondary ion mass spectrometry (SIMS), the detection of large organic molecules is accomplished using cluster ion bombardment. Ion formation often proceeds via cationization, through the attachment of (alkali) metal ions to the molecule. To study this process and its efficiency, the emission of secondary ions sputtered from polyethylene glycol (PEG 3000) mixed with Na trifluoroacetic acid (NaTFA) was investigated for 10 keV A r 2000 + cluster irradiation by MS and MS/MS. Apart from cationized molecular ions [M n +Na] + (with repeat units n of up to ∼80), fragment species were found corresponding to the loss of a water moiety or of two H atoms, respectively. In addition, an abundant flux of doubly-charged molecular ions, [M n +2Na] 2+ was observed in the mass spectra. Quite surprisingly, even triply-charged ions [M n +3Na] 3+ were detected. The ratio of [M n +2Na] 2+ to [M n +Na] + increases with increasing size of the molecules and reaches unit for n ∼70. The yield of [M n +Na] + ions around m / z 3000 depends strongly on the molecular composition ratio of NaTFA/PEG in the samples and can be enhanced by a factor of 50 by increasing the Na content. In MS/MS operation, [M n +Na] + and [M n +2Na] 2+ ions were subjected to collisions with Ar atoms; for sufficiently high collision energies, dissociation leads to characteristic fragment species. Collisions of [M n +2Na] 2+ assert the existence of doubly-charged ions in the sputtered flux. Collision cross sections were found to amount to ∼(0.5–1)×10 −15  cm 2 for center-of-mass collision energies of ∼3 eV. [ABSTRACT FROM AUTHOR]

A novel and recyclable bioadsorbent (PTP) has been prepared by the cationization of persimmon tannin (PT) using polyethyleneimine (PEI) for application in the removal of the anionic dye methyl orange (MO) from aqueous solution. The physicochemical properties of the prepared PTP were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, Zeta potential measurements, Brunauer-Emmett-Teller and thermogravimetric analysis. Systematic batch adsorption experiments were carried out with pH, bioadsorbent dosage, initial MO concentration and contact time. Kinetic regression analysis indicated that the adsorption processes followed the pseudo-second order model. The equilibrium isotherm was in good fit with the Freundlich model with a maximum adsorption capacity of 225.74 mg/g. Thermodynamics data revealed that the adsorption of MO onto PTP was feasible, spontaneous and endothermic. A possible biosorption mechanism was presented where electrostatic interactions, hydrogen bonding, and π-π interactions dominated the adsorption of MO onto PTP. Moreover, the regeneration of the PTP was easily achieved and MO removal efficiency remained high (81.47%) after six cycles. The actual sewage treatment simulation was evaluated and the PTP had a good preference to adsorption MO. All these results indicated that PTP could be considered a high performance and promising candidate for the effective removal of anionic dyes from aqueous solutions. [ABSTRACT FROM AUTHOR]

In the present study, cationized high amylose maize starches (CS) with different degrees of substitution (DS) were prepared. The physical properties and microstructures of CS/montmorillonite (Mt and D1821Mt) films were investigated. Morphological analysis showed stronger intercalations of CS with hydrophilic montmorillonite (Mt) than with hydrophobic montmorillonite (D1821Mt). For CS/Mt nanocomposite films, an increasing exfoliation trend was detected with the increase in DS. On the whole, the tensile strength of CS/Mt nanocomposite films decreased while water vapor permeability increased with an increase of DS. The CS/Mt film with the DS of 0.04 showed the highest tensile strength (14.01 MPa) and lowest water vapor permeability (1.80 × 10 −10  g m/m 2  s Pa). Rheological measurements confirmed that the intermolecular forces between CS and Mt decreased with increasing DS. Mt could obviously increase the thermal stability of the films. Overall, CS with lower DS had better compatibility with Mt, which helped improve the properties of CS/Mt nanocomposite films. [ABSTRACT FROM AUTHOR]

Copyright of Lucrari Stiintifice, Universitatea de Stiinte Agricole Si Medicina Veterinara Ion Ionescu de la Brad Iasi, Seria Horticultura is the property of University of Agricultural Sciences and Veterinary Medicine (Editura Ion Ionescu de la Brad) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Dissolution, dispersion, and aggregation characteristics of 2-hydroxy-3-trimethylammoniopropyl polysaccharides made from β-1,3-glucan extracted from Euglena (referred to as paramylon) differing in the degree of substitution (DS) of a 2-hydroxy-3-trimethylammoniopropyl group were examined. Freeze-dried solids made from cationic paramylon derivatives with a DS ranging from 0.07 to 0.16 spontaneously formed crystalline nanofibers upon being mechanically stirred in water. Derivatives with a DS greater than 0.31 lacked similar fiber formability. Nevertheless, they formed a distinctly outlined, transparent thin film featuring a nanometerlevel flat surface using an aqueous solution casting method in which water is gradually removed from the aqueous homogeneous solution and a methanolic solution casting method featuring rapid removal of methanol from a heterogeneous solution. Those that had a DS less than 0.06 lacked solution solubility and dispersibility; they formed a thin film from a heterogeneous solution. These results demonstrate that cationic paramylon derivatives can be used as a constituent of well-organized polymeric materials. [ABSTRACT FROM AUTHOR]

Fuel upgrading is one of the globally requirements due to struggle the environmental impacts and to protect the humanity. Presence of oxygenated compounds such as phenol in liquid fuel caused serious problems in the fuel combustion and gums formation in the interior engines and consequently blocking the fuel filter. These problems are directly affected on both of the human's life and environment. Herein, functionalized viscose fibers were designed and applied for liquid fuel purification from phenol. Viscose fibers was firstly cationized by interaction with N-2-chloroethyl N,N diethyl ammonium chloride to produce cationized fibers with nitrogen contents of 0.32–0.52%. Sorption of phenol from n -octane by using the cationized fibers was systematically studied. Sorption capacities were significantly affected by the degree of substitution and were linearly increased with nitrogen contents. The maximum sorption capacities were 178.6 and 206.2–282.5 mg/g for untreated and cationized fibers, respectively. Sorption was obeyed to pseudo-second order and signified that cationization process accelerates the phenol removal process. Sorption of phenol onto fibers were well followed Langmuir isotherm profile which reflected the monolayer sorption. Sorption was taken place via weak interactions between phenol molecules and substituted functional groups of fibers achieving physisorption process. However, the maximum capacity was diminished by regeneration process, the maximum removal of phenol was 80% after 4 regenerated cycles. Cationized viscose fibers can be considered as quite good template to purify liquid fuel from phenols, able to apply several times with good economic viability. [ABSTRACT FROM AUTHOR]

Although the environmental performance of the paper industry has drastically improved since the nineties, Western manufacturers still refuse to reuse agricultural waste. Moreover, papermakers make extensive use of poorly biodegradable polyelectrolytes which are toxic to fish. With this in mind, we suggest pulping lignocellulosic residues by sulfur-free processes, decrystallizing cellulose, and introducing positively charged functional groups with the goal of partially replacing conventional cationic polymers. Functionalization of pulps from orange tree trimmings, rapeseed stalks and wheat straw was carried out with different concentrations of (3-chloro-2-hydroxypropyl)trimethylammonium chloride (CHPTAC). When the mole ratio of CHPTAC to anhydroglucose units was 4, cationic fibers reached charge density values over 0.2 meq/g after 40 or 60 min of reaction. Then, we tested the performance of these fibers in papermaking, using titanium dioxide, whose zeta potential is negative, as filler. Opacity of lightweight paper was raised to 90%, surpassing a conventional cationic polyacrylamide (CPAM), while the increase in brightness (from 37.8% to 41.9%) was not as good as that achieved with CPAM. Even if residues cannot replace wood, chemical modifications of them can result in valuable cationic fibers, making synthetic polyelectrolytes less necessary. [ABSTRACT FROM AUTHOR]

Cationic derivatives of konjac glucomannan (KGM) were homogeneously synthesized by reacting KGM with 3-chloro-2-hydroxypropyltrimethylammonium chloride (CHPTAC) in NaOH/urea aqueous solutions. The derivatives were characterized by FT-IR, 1 H NMR, elemental analysis, thermogravimetric analysis and zeta potential analysis. The results showed that the degree of substitution (DS) of the CKGM with the value of 0.15–0.46 could be obtained by changing the molar ratio between KGM and CHPTAC. The TG/DTG revealed that the thermal stability of KGM after cationization was lower than that of raw KGM. Among a wide range of pH value, the zeta potential in CKGM solution was shown with positive charges. The flocculation capacity of the CKGM was assessed through Kaolin suspension using the light transmission test. The results exhibited that the CKGM had excellent flocculation performance and could be used as an emerging flocculant agent in the wastewater treatment. [ABSTRACT FROM AUTHOR]

Copyright of Tekstil: Journal of Textile & Clothing Technology is the property of Croatian Association of Textile Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work, untreated starch-rich potato peel waste was used as a starting material in preparation of cationized starch (CS) 1 in water solution with 2-chloro-3-hydroxypropyltrimethylammonium chloride (CHPTAC) as the cationization reagent. The impact of various factors (activation time, temperature, reaction time, the amount of CHPTAC and NaOH) on the degree of substitution (DS) of CS was studied by using experimental design. The DS values were determined by 1 H NMR. The highest DS (0.40) was obtained when the reaction time was 8 h, temperature 30 °C, the molar ratio of CHPTAC and NaOH to AGU 3 and 3.75, respectively. The prepared CS was successfully used to remove sulfate ions from an aqueous solution with ultrafiltration technique. Sulfate is a major pollutant of water bodies so development of efficient techniques for its removal is detrimental. The removal of sulfate in study was 74% at best. [ABSTRACT FROM AUTHOR]

Antibodies and fragments thereof are, because of high selectivity for their targets, considered as potential therapeutics and biomarkers for several neurological disorders. However, due to their large molecular size, antibodies/fragments do not easily penetrate into the brain. The aim of the present study was to improve the brain distribution via adsorptive-mediated transcytosis of an amyloid-beta (Aβ) protofibril selective F(ab’) 2 fragment (F(ab’) 2 -h158). F(ab’) 2 -h158 was cationized to different extents and the specific and unspecific binding was studied in vitro . Next, cationized F(ab’) 2 -h158 was labelled with iodine-125 and its brain distribution and pharmacokinetics was studied in mice. Cationization did not alter the in vitro affinity to Aβ protofibrils, but increased the unspecific binding somewhat. Ex vivo experiments revealed a doubling of brain concentrations compared with unmodified F(ab’) 2 -h158 and in vivo imaging with single photon emission computed tomography (SPECT) showed that the cationized F(ab’) 2 -h158, but not the unmodified F(ab’) 2 -h158 could be visualized in the brain. To conclude, cationization is a means to increase brain concentrations of therapeutic antibodies or fragments and may facilitate the use of antibodies/fragments as imaging biomarkers in the brain. [ABSTRACT FROM AUTHOR]

Reactive dyeing of cotton garments involves two stages, namely exhaustion and fixation of dyes. The exhaustion stage in reactive dyeing requires high quantity of salt. After dyeing process, the highly saline coloured effluent is discharged and the treatment of this effluent at present is not economically viable and making industries look for other alternatives for usage of salt. Cationization of cotton is one of the effective alternatives to overcome the usage of the salt. The present work focuses on the exhaust method of cationization of garments at an industrial scale using 3-chloro-2-hydroxypropyl trimethylammonium chloride as a cationic agent. Two commercially popular reactive dyes namely Navy Blue and Green dyes were chosen for dyeing the garments at 10% shade. The results of dyeing were evaluated on the basis of colour strength, dyeing levelness and colour fastness. The uniformity of dye on the fabrics was evaluated based on dyeing levelness and was found to be good for cationized cotton dyed garments. The fastness properties of dyed fabrics to washing and light were good. The dye utilization in the cationized cotton dyed garments was twice as that of the conventionally dyed cotton garments. The environmental hazard posed by the highly saline coloured effluent could be easily mitigated by the salt-free reactive dyeing process. [ABSTRACT FROM AUTHOR]

The primary objective of this work was to generate dyes sites in cotton fiber for acid dyes via free radical graft polymerization of diallyldimethylammonium chloride (DADMAC), to confer cationized cotton, and evaluate the dyeability of the cationized cotton toward acid dyes, which is unprecedented. Plasma-induced graft polymerization of DADMAC on cotton, using different plasma conditions, followed by dyeing with different acid dyes was studied. The color yield of dyed cotton was evaluated usingK/S. Light fastness, color change, and staining following accelerated washing cycles were carried out to evaluate the effectiveness of cotton cationization. Cross-section dyed cotton was studied using scanning electron microscopy and showed deep dyeing of acid dyes into cotton fibers. This approach resulted in significant dye uptake into the fibers and considerably reduced the need for effluent treatment. [ABSTRACT FROM AUTHOR]

Cationization is a promising chemical modification technique that improves properties by attaching permanent positive charges to the backbone of biopolymers. Carrageenan is a widely available and non-toxic polysaccharide, commonly used in food industry but with low solubility in cold water. We performed a central composite design experiment to check the parameters that most influence the degree of cationic substitution and the film solubility. Hydrophilic quaternary ammonium groups on the carrageenan backbone enhance interaction in drug delivery systems and create active surfaces. Statistical analysis indicated that within the studied range, only the molar ratio between the cationizing reagent and the repeating disaccharide unit of carrageenan had a significant effect. Optimized parameters using 0.086 g of sodium hydroxide and glycidyltrimethylammonium/disaccharide repeating unit of 6.83 achieved 65.47 % degree of substitution and 4.03 % solubility. Characterizations confirmed the effective incorporation of cationic groups into the commercial structure of carrageenan and thermal stability improvement of the derivatives. [Display omitted] [ABSTRACT FROM AUTHOR]

Cationic starches were obtained from native starch extracted from cassava of three different varieties at different temperatures (28-50°C) and reaction times (7-24h) using 2,3-epoxypropyltrimethylammonium (EPTAC) as cationizing reactive and NaOH as catalyst in a dry process at ethanolyc medium. The effect of these three factors in the degree of substitution (DS), the reaction efficiency (RE) and functional properties of starch were studied. Degree of substitution (DS) of the cationic starches and functional properties are not significantly affected by the reaction conditions except for the gelatinization temperature, which is affected by the reaction temperature. Starches were obtained with low degrees of substitution between 0.009 and 0.023. Further, the functional properties studied in cationic starches are better than native starches.

Palytoxin (PlTX) and analogues are produced by certain dinoflagellates, sea anemones, corals and cyanobacteria. PlTX can accumulate in the food chain and when consumed it may cause intoxication with symptoms like myalgia, weakness, fever, nausea, and vomiting. The analysis of PlTXs is challenging, and because of the large molecular structure, it is difficult to develop a sensitive and selective liquid chromatography-mass spectrometry (LC-MS/MS) method. In this work, an LC-MS/MS method was developed to analyse PlTXs with use of lithium iodine and formic acid as additives in the mobile phase. For method development, initially, LC-hrMS was used to accurately determine the elemental composition of the precursor and product ions. The main adduct formed was [M + H + 2Li]3+. Fragments were identified with LC-hrMS and these were incorporated in the LC-MS/MS method. A method of 10 min was developed and a solid phase extraction clean-up procedure was optimised for shellfish matrix. The determined limits of detection were respectively 8 and 22 µg PlTX kg−1 for mussel and oyster matrix. Oysters gave a low recovery of approximately 50% for PlTX during extraction. The method was successfully in-house validated, repeatability had a relative standard deviation less than 20% (n = 5) at 30 µg PlTX kg−1 in mussel, cockle, and ensis, and at 60 µg PlTX kg−1 in oyster.

In this study, the cationic Poly[Styrene-Butyl acrylate-(P-vinylbenzyl trimethyl ammonium chloride)] P(St-BA-VBT) nanospheres with N+(CH3)3 functional groups were successfully synthesized by soap-free emulsion polymerization and applied to different fabrics by pad-cure process. After the pad-cure process, the nanospheres were deposited on the surface of the modified cotton fibers successfully without forming a continuous film structure. The X-ray Photoelectron Spectroscopy (XPS) and the Fourier transform infrared (FTIR) results demonstrated that P(St-BA-VBT) nanospheres were adsorbed on the surface of cotton fibers successfully. The excellent color strength value and outline sharpness of the plain, twill, and honeycomb fabrics can be achieved when the nanosphere concentration, sodium bicarbonate, and steaming time were 1 g/L, 10 g/L, and 6 min, respectively. The plain fabrics exhibited the smallest color strength (K/S) values and the best outline sharpness, followed by twill and honeycomb fabrics, which displayed the largest K/S values and the worst outline sharpness after the same treatment. Besides, all the three fabrics showed excellent rubbing fastness and washing fastness. The cationic P(St-BA-VBT) nanospheres modification of the cotton fabrics provides a novel potential approach to obtain good printing efficiency without affecting the tensile breaking strength of cotton fabrics significantly.

Hardwood organosolv lignin (OSL) and enzymatic hydrolysis lignin (EHL) from softwood were cationized by glycidyltrimethylammonium chloride (GTAC) as new lignin starting materials for the reaction. The products were in detail characterized by 31 P-NMR to elucidate the reactivity of different lignin functionalities in cationization with GTAC. For OSL, a high cationization level (degree of substitution 0.74) was reached leading to a water-soluble product. For EHL, low solubility and lower reactivity were observed, likely due to the high saccharide content. Further, lower reactivity of the guaiacyl type lignin present in softwood, compared to syringyl type lignin in hardwoods, which was shown to react efficiently during the derivatization of OSL, probably played a role. In parallel to cationization, an increase of carboxylic acids (from 0.03 up to 0.55 mmol/g) in the lignin was observed as an unexpected side reaction, possibly as a result of alkaline oxygen oxidation. The applicability of the cationized lignins was tested for water purification applications in three model systems which have only sparingly been studied with cationized lignins. GTAC-OSL and GTAC-EHL were found promising for sulfate removal, with sulfate sorption capacities of up to 54 mg/g. GTAC-OSL was also found suitable for promoting kaolin settling and to some extent for humic acid coagulation. [ABSTRACT FROM AUTHOR]

Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to produce deep shades of colour, ramie fibre was subjected to pretreatment by cationization, caustic mercerization (slack and tension condition), and liquid ammonia mercerization. The untreated and pretreated samples were dyed with 0.5 to 7 % concentrations (on mass of fiber (o.m.f)) of Liyuansol Red FL-2BL reactive dye. The dyeing properties of dye exhaustion, fixation, colour uniformity, wash fastness, and rubbing fastness were investigated. The results indicated that these pretreatments improved dye exhaustion and fixation on ramie fibre, with no loss of fastness. For the untreated and treated substance, the amount of dye mass absorption increased linearly with increased dye o.m.f. Cationic treatment improved performance, with 89 % and 98 % for exhaustion and fixation, respectively, and the maximum K/ S values of all fibers receiving pretreatment. The colour uniformity was acceptable and similar for the untreated and treated ramie fibers, with the exception of cationic-treated fabric dyed at 7 % dye o.m.f that showed a high standard deviation value of colour uniformity. The Freundlich and Langmuir adsorption isotherm models were also used to study the adsorption of dye on ramie fibre; all of the adsorption processes fit the Freundlich model. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) was used to reinforce paper sheets made from non-woody fibers, e.g. sugarcane bagasse. BC produced from static and agitated fermentation methods was mixed with bleached sugarcane bagasse pulp (BSBP) to produce composite paper sheets. BC from static culture had a higher degree of polymerization, crystallinity, and crystallite width. Adding BC at a low ratio (<1% of the dry weight of the sheets) can effectively improve the mechanical properties of BSBP paper sheets. Adding static BC improved the tensile index of BC-BSBP composite sheets up to 25%. Furthermore, BC was also chemically modified or cationized by reacting with (3-chloro-2-hydroxypropyl)trimethylammonium chloride. The results demonstrated that the cationization reaction had to be maintained at a low level (DS < 0.005) for effective improvement in mechanical properties of the BC-BSBP composite sheets. The improvements in tensile index were up to 10 and 32%, compared to the unmodified BC-reinforced sheets and sheets without BC, respectively. The low addition and low cationization levels suggest an economical prospect for static BC being used in the paper-based material industries to improve the qualities of non-woody fiber products. [ABSTRACT FROM AUTHOR]

In this work, composites were made by improved bonding of the cationized cellulosic fabric and some anionic matrix like Carboxymethyl Cellulose (CMC). Mercerized cotton fabric was cationized using cationization agent, TEXAMIN ECE with varying percentage from 1 to 10%. Those cationized cotton samples were incorporated in anionic matrices and the resultant composites were tested for mechanical properties on Universal Textile Tensile Testing machine. In the case of CMC as the matrix for the cationized reinforcement, the increasing trend in the tensile strength and elongation at break was observed. Scanning Electron Microscope images showed no extraordinary changes in the physical appearance of the cationized samples. Thermograms derived from Differential Scanning Calorimetry were informative for the evaluation of the thermal behavior of composites. [ABSTRACT FROM AUTHOR]

Water-soluble cationic cellulose derivatives were synthesized by three different procedures, cationizing bleached hardwood kraft pulp with (3-chloro-2-hydroxypropyl) trimethylammonium chloride. The first procedure involved a previous depolymerization step with orthophosphoric acid. The second one consisted on dissolving cellulose in NaOH/urea before cationization. For the third procedure, the reaction medium was heterogeneous since it was carried out with a part of cellulose with high degree of polymerization. Oppositely to the common methods, cationization occurred under mild conditions. Differences among the three derivatives are illustrated by X-ray diffraction patterns of pretreated samples, infrared spectra, and determinations of the degree of substitution, the zeta potential, the charge density and the molecular weight. The performance of these polyelectrolytes for the flocculation of mineral fillers used in papermaking was tested by laser diffraction spectrometry. The flocculant with the highest degree of polymerization and charge originated the best results, particularly when the filler used was kaolin, proving that water-soluble cationic cellulose derivatives can aid in the flocculation of fillers used in papermaking. On the contrary, the shortest-chained derivative was not effective. The results were interpreted in terms of the characteristics of the cellulose derivatives flocculants and of the fillers, and neutralization and patching were proposed as the dominant mechanisms. [ABSTRACT FROM AUTHOR]

ABSTRACT This study aims to modify admicellar polymerization (AP) of polypyrrole (PPy) by increasing the adsorption of sodium dodecyl sulfate (SDS) on cotton fabric. The PPy films were formed on the pristine and precationized cotton samples using the AP method. The samples were characterized by UV-Vis and attenuated total reflection Fourier transform infrared spectroscopic techniques, scanning electron microscopy (SEM), and the standard two-probe method. The adsorbed amounts of SDS showed an increase up to 37% in the cationized samples. Both infrared spectroscopy and SEM images confirmed the formation of PPy layers on uncationized and cationized cotton samples. The agglomeration of PPy particles was also appeared on the uncationized fibers. However, a uniform distribution of PPy films was observed for the cationized cotton fabrics. Furthermore, the conductivity of these samples enhanced up to 49% (with a 0.0212 S/cm electrical conductivity). It was concluded that cotton precationization could result in a fabric with a very low resistance or improved conductivity. [ABSTRACT FROM AUTHOR]

Compared to chemical pulp, mechanical and chemi-mechanical pulps (CMP) are limited in regards to the manufacturing of high quality paper. Chemical additives are an effective way to enhance the properties of paper; however, the effectiveness depends on the additive type and dosage. The utilization of cationized natural polymers has been shown to offer a promising solution. In this study, softwood long fiber (SLF) and CMP were cationized by 3-chloro-2-hydroxypropyl-trimethylammoniumchloride (CHPTAC), and the effects of cationization on the properties of CMP pulp were studied. Cationization was characterized by FTIR and the nitrogen content, and its effect on the CMP properties was evaluated through mechanical tests and fines retention. Cationization at low and moderate levels and in higher mixing rates improved the mechanical properties of CMP. Compared to cationized CMP, the addition of cationized SLF (CLF) improved the strength and fines retention properties. The CLF application to CMP at a CHPTAC dosage of 5% increased the tensile, burst, and tear strengths by 66.4%, 100%, and 3.6%, respectively. The cationized SLF increased the fines retention by 12.7%. [ABSTRACT FROM AUTHOR]

Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is often applied to assess the dispersity and the end groups of synthetic polymers through the addition of cationizing agents. Here we address how these cation adducts are formed using polystyrene (PS) as a model polymer. We analyzed PS by MALDI-MS with a 2-[(2 E )-3-(4- tert -butylphenyl)-2-methylprop-2-enylidene]malononitrile (DCTB) as the matrix and a range of trifluoroacetate (TFA) salts as cationizing agents on a range of different target plate materials (copper, 1.4301 stainless steel, aluminum, Inconel 625, Ti90/Al6/V4 and chromium-, gold- and silver-plated stainless steel). It was found that on a stainless steel substrate the metal cations Al + , Li + , Na + , Cu + and Ag + formed polystyrene adducts, whereas K + , Cs + , Ba 2+ , Cr 3+ , Pd 2+ , In 3+ , or their lower oxidation states, did not. For the copper and silver substrates, PS and DCTB adduct formation with cations liberated from these target plate materials was observed upon addition of a cationizing agent, which indicates the occurrence of redox reactions between the added TFA salts and the target plate material. Judging from their standard electrode potentials, these redox reactions would not normally occur, i.e., they require an additional energy input, strongly suggesting that the observed redox reactions are laser-induced. Furthermore, copper granules were found to successfully sequester PS from a tetrahydrofuran (THF) solution, consistent with the view complex formation with the copper target plate can take place prior to the MALDI-MS measurement. [ABSTRACT FROM AUTHOR]

Fibers resulting from pulping of wood are negatively charged by nature. This charge might be reversed by chemical modification for different applications. In this study, different options to determine the degree of substitution (DS) with cationic groups introduced using 2,3-epoxypropyltrimethylammonium chloride, a common cationization reagent, are compared. Classical analytical methods for this purpose include elemental analysis, which is unspecific, and titration, which is sensitive toward impurities and highly elaborate. These are complemented by fast and robust approaches based on infrared spectroscopy or thermogravimetric analysis. The absorption increase at 1480 cm−1is specific for the introduced R-NMe3and linearly correlated with the DS. For bleached Kraft pulps, cationization splits the thermal degradation of cellulose in two phases, their ratio being roughly proportional to the DS. Both methods require virtually no sample preparation. Infrared spectroscopy is particularly easy to apply and allows a quantification of pulp cationization in short time. [ABSTRACT FROM PUBLISHER]

Nanocrystalline cellulose (NCC) is a promising nanofiller for reinforcing chitosan (CTS) film. The flocculation of the NCC suspension in acidic CTS solution is the key problem that makes many properties such as the tensile strength bad. A derivative of nanocellulose, namely cationic dialdehyde cellulose (CDAC), is synthesized in the current study to avoid the flocculation. A CDAC suspension is prepared in a successive oxidation-reductive amination process of NCC. The oxidation of NCC led to smaller rod-like nanocrystals with a reduced crystallinity. The suspension with 1.0% CDAC is well mixed with 1.0% CTS solution. Besides, the tensile strength and anti-swelling properties of CDAC-filled CTS nanocomposite films are improved because of the uniform distribution of CDAC in the CTS matrix plus the intermolecular chemical cross-linking between CDAC and CTS. The tensile strength of CTS-based nanocomposite film with 12% CDAC is about 58.4% higher than that of the pure CTS film. [ABSTRACT FROM AUTHOR]

As its abundant reserves and good physical properties, bamboo is deemed to be a promising feedstock material for construction and home furnishing. However, the hydrophilicity of bamboo and its rich nutrients make it susceptible to mold infection. In this study, bamboo firstly reacted with 0, 3, 6, 9, and 12 wt times of 2,3-epoxy-propyltrimethylammonium chloride (EPTAC) in NaOH/Urea solution, respectively, and then impregnated with rosin acid. Effects of modification on structure, thermal stability and water repellency of bamboo were identified by FT-IR, XRD, XPS, SEM, TGA, contact angle measurement and water absorption coefficient, respectively. A comparative study of mold-proof properties of original and modified bamboo was conducted as inoculation of Aspergillus niger , Penicillium citrinum and Trichoderma viride on samples. The results indicated that the sample obtained from a mass ratio (EPTAC to bamboo) of 9 had the highest substitution degree, charge content and ion exchange capacity as compared to samples obtained from other EPTAC dosages. After modification, the density of bamboo increased by 43.3%, which exhibited considerable thermal stability. Impregnating this sample with rosin acid improved its water-repelling and anti-swelling efficiency to 10.91% and 27.83%, respectively. Compared with the original bamboo, anti-mold property of EPTAC modified bamboo to three fungi was notably improved and achieved rate 1 mold coverings. Impregnation-modified bamboo with rosin acid enhanced the anti-mold property, achieving a rate of 0 mold covering. The research provides a feasible way to improve the mildew resistance of bamboo and promote the utilization of rosin. [Display omitted] • The quaternary ammonium groups was introduced to the surface of bamboo to improve its antifungal properties. • Rosin impregnation enhanced cationic bamboo's water repellency and dimensional stability. • The impregnated rosin improved the mildew resistance of cationic bamboo. • Cationization and rosin impregnation improved the water repellency and mildew resistance of bamboo. [ABSTRACT FROM AUTHOR]

The present work reports on cationization characteristics of organic molecules in alkali metal environment. Samples of arginine and polyethylene glycol polymers with average masses of 600, 1000 and 1500 were mixed with sodium- and potassium trifluoroacetate of various concentrations, and analyzed through secondary ion mass spectrometry. Bombardment proceeded with ions within both keV and MeV energy domains. Added salts positively affected the secondary ion yield through attachment of Na or K to organic molecule. Ionization differences between swift (MeV) ions and cluster ions, commonly used for secondary ion mass spectrometry analysis, were studied for arginine and PEG 600. While for arginine, secondary ion yield enhancement was only by a factor of 2, when analysing with MeV ions, and no enhancement was observed with keV Bi 3 clusters, all polyethylene glycol samples showed increase of the secondary ion yield by factors between 3 and 40, depending on the amount of potassium or sodium that was mixed into the matrix. Additionally, higher amounts of salts also resulted in decreased fragmentation probability for organic molecules, reducing the intensities of specific fragments by more than two orders of magnitude. [Display omitted] • Added salts significantly increase secondary ion yield for both keV and MeV primary ions. • Ionization increase due to salt addition is greater with keV SIMS. • Added matrix reduces fragmentation – more with MeV-SIMS. • With secondary ion yields of approx. 10−2, submicron molecular imaging is feasible. [ABSTRACT FROM AUTHOR]

Bleached cotton fabric was chemically modified (cationized)with natural amino acids extract obtained by acid hydrolysis (6N HCL) from soya bean seed waste, adding MgCl2 as an acid donor in the pad-dry-calendaring process to investigate the changes in textile properties and its dyeability with reactive dye in both a conventional alkaline dye bath and salt-free acidic dye bath. This modified cotton incorporates new functional groups producing -NH3 + in acid bath to obtain cationized cotton, rendering it to eco-friendly salt-free reactive dyeing at acceptable shade depth without much sacrifice of other textile-related properties. Bi-functional high exhaustion-type reactive dye shows better dye uptake than mono-functional cold brand as well as hot brand reactive dye. Moreover, the application of a specific dye fixing agent further improves surface color depth (K/S) of the soya-modified cotton fabric. The study of surface morphology of said chemically modified cotton substrate indicates a higher degree of surface deposition, that is, more anchorage of soya extracted amino acids on cotton fabric. Chemical anchorage as per the reaction scheme postulated for such modifications is verified with Fourier transform infrared spectroscopy. Finally, it is revealed that cotton treated with soya extract provides a new route of eco-friendly salt-free reactive dyeing with high exhaustion-type reactive dyes showing much higher dye uptake than the control cotton fabric. [ABSTRACT FROM AUTHOR]

After successful cationization of cellulose nanocrystals (CNCs) to produce pyridinium-grafted-CNCs, a variety of different cationic CNCs were prepared using a similar procedure, thus unlocking access to a wide variety of cationized cellulose nanocrystals through a simple one-pot reaction. In this study, cationic CNCs were prepared through the use of 4-(1-bromoethyl)benzoic acid or 4-bromomethylbenzoic acid, p-toluenesulfonyl chloride, CNCs, and two different amines, 1-methylimidazole and 4-dimethylaminopyridine. The amines acted as both the base catalyst for the esterification and the nucleophile to form the cationic charge. This method offers a versatile and straightforward route to prepare a variety of different cationic nanocrystals and therefore tailor their interaction with their environment. [ABSTRACT FROM AUTHOR]

Cattle hoof and horn keratin hydrolysate from cattle hoofs and horns were successfully extracted and used to cationize cotton fabric. The effect of cationization was tested by dyeing the cationized cotton fabric using reactive dyes (cationized sample). The results were compared to conventionally dyed cotton fabric sample without cationization. The UV/VIS absorption result showed 6% improvement in exhaustion; the Color EyeK/Sresult gave 4.5% improvement in fixation and 6.8% in dye utilization for reactive dye (H-Reactive Red). Acceptable color fastness to washing (4/5) and light fastness (7) were achieved on cationized sample. [ABSTRACT FROM PUBLISHER]

Mechanical and chemi-mechanical pulps such as CMP, due to the weaker strength properties, have found limited application in the production of high quality papers as compared with chemical pulps. Therefore, appropriate modification of such fibers could be used to overcome such deficiencies. This study investigated the effect of cationic pretreatment of the CMP fibers to improve the potential of the fibers in paper production. First, fibers were treated by 20% sodium hydroxide, and then the fiber surface was cationized by grafting with one of the dosages of 5, 10 and 15% EPTMAC, based on fiber oven dry weights. The cationized fibers were mixed with 100, 20 and 40 % non-cationized fibers and the mixture was used to make hand sheets. The tensile and burst indices of the hand sheets were measured. The highest tensile and burst indices were measured on hand sheets produced containing either 20 or 40% fibers grafted with 10% cationic agent.

Chemical cationization of cotton has been a subject of increased interest due to the ability of cationized cotton to attract negatively charged dyes, thus eliminating the use of electrolytes during dyeing and increasing color yield. However, electrostatic attractions between cationized cotton and anionic dyes also result in significantly increased dye strike rates, which may cause levelness problems, especially when light to medium shades are required. In this study, cotton fabric cationized using 3-chloro-2-hydroxypropyl trimethylammonium chloride was used to investigate the method for obtaining appropriate dye strike rate to produce a level reactive dyeing on cationized cotton. To effectively control the dyeing kinetics of reactive dyes on cationized cotton, real-time exhaustion of six commercially significant reactive dyes were monitored. The influence of temperature, dye structure, and addition of soda ash on dyeing kinetics and levelness of cationized cotton were evaluated. [ABSTRACT FROM AUTHOR]

Hybrid materials based on cellulose nanofibrils (CNF) and gold nanoparticles (AuNPs) are synthesized and novel routes to couple AuNPs on the CNF surface are introduced. Quaternary ammonium, azido, alkyne and amino functional groups were used for the attachment of metal particles on the corresponding functionalized CNF (EPTMAC-CNF, Azido-CNF, Propargyl-CNF, Amino-CNF, respectively). The CNF-based supports were characterized by Fourier transform infrared spectroscopy and the surface charge was assessed by ζ-potential measurements. The AuNPs were attached on the functionalized CNF surface via either electrostatic interactions or click reactions. The obtained CNF/AuNPs hybrid materials were characterized using transmission electron microscopy (TEM) and inductively coupled plasma optical emission spectrometry. The obtained Bio-inorganic hybrid materials are potentially suitable for surface-enhanced Raman scattering, chemosensing and catalytic applications. [ABSTRACT FROM AUTHOR]

A hairy cationic nanocellulose (CNCC) was prepared by a two-step reaction. First dialdehyde modified cellulose (DAMC) were prepared by periodate oxidation of cellulose fibers and subsequently DAMC fibers were cationized by a reaction between the aldehyde groups of cellulose and (2-hydrazinyl-2-oxoethyl)-trimethylazanium chloride [Girard's reagent T (GT)] to produce cationic dialdehyde cellulose (CDAMC) fibers. Subjecting the suspension of CDAMC fibers to a hot-water treatment at 60 °C, resulted in the formation of cationic rod-like nanocellulose (CNCC). Atomic force microscopy and transmission electron microscopy showed the CNCC has a width of 5 nm and a length about 120 nm. Zeta potential measurement, Fourier transform infrared spectroscopy, solid carbon-13 NMR and X-ray photoelectron spectroscopy confirmed the presence of cationic groups on CNCC. The positive charge content of CNCC is about 1.68 mmol/g measured by conductometric titration. CNCC has a crystalline index of 67 % and possesses cellulose I crystalline structure. [ABSTRACT FROM AUTHOR]

Researchers have studied the cationization of polysaccharides to replace conventional cationic polyelectrolytes, linked to environmental issues. However, cationic celluloses have not achieved the success of cationic starches. The knowledge of the cellulose cationization proccess needs to be improved. In this work, we pretreat (alkalize) and cationize cotton linters and α-cellulose powder, using 3-chloro-2-hydroxypropyltrimethylammonium chloride (CHPTAC) in an aqueous-alcoholic alkaline solution. The pretreatment took place under different conditions, whereas the cationization itself was always performed at 70 ºC, for a CHPTAC/AGU (anhydro glucose units) mole ratio of 4, and for a total time of 5 h for cotton linters or 100 min for α-cellulose powder. The degree of substitution, the crystallinity index and the temporal evolution of intrinsic viscosity are provided for the 18 experiments performed. The background was uncertain about the effect of cationization on intrinsic viscosity. Here, we report increasing viscosity with increasing degree of substitution and cationization time. Furthermore, intrinsic viscosity increased with increasing cationization time, even when the degree of substitution had leveled off. Seemingly, the incorporation of positive charges into cellulose changed the polymer distribution and the interactions between the polymer and the solvent. [ABSTRACT FROM AUTHOR]

Textile effluents are characterized by high chemical oxygen demand, biological oxygen demand, total dissolved solids, pH and colour. Fabric preparation steps, such as desizing, scouring, bleaching and mercerizing, use various chemicals and plenty of water. The occurrence of unfixed dyes and other electrolytes in effluents poses serious threats to the environment. Available end-of-pipe treatment procedures are either expensive or not efficient; hence, a large number of small-scale industries succumb to this problem. So, finding an alternative eco-friendly process of textile production is of paramount interest. Here, we review three potential eco-friendly systems applicable to textile dyeing processes to minimize salt and water consumption. First, we review application of enzymatic processing in fabric preparation. Secondly, we review the use of biodegradable organic salts, such as trisodium citrate, magnesium acetate, tetrasodium edate and sodium salts of polycarboxylic acids, as fixation and exhaustion agents. Finally, we review various surface modifications of cotton to reduce the volume of effluent and total dissolved solids. [ABSTRACT FROM AUTHOR]

In this paper, milled corncob powder was treated with sodium chlorite to remove lignin, and the resulting holocellulose was optionally modified with cationic agent. The derivative product was investigated using elemental analysis, Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). The influences of the dosage of the cationic agent, reaction temperature, particle size, dosage of paper strengthening agent, and pH value of the pulp on the paper physical properties were studied. The results indicated that cationic corncob holocellulose can improve the tensile index, burst index, and folding endurance of paper. When the dosage of cationic agent was 25% and the reaction temperature was set to 70℃, the resulting tensile index, burst index, and folding endurance increased by 7.15%, 13.74%, and 55.95%, respectively, when compared with the control paper. The particle size of the raw material and the dosage of strengthening agent also greatly influenced the paper's properties. The SEM analysis showed that the combination of fibers improved the strength properties of the paper after adding the strengthening agent. These results provide a method for value-added use of corncob waste. [ABSTRACT FROM AUTHOR]

As an important cellulose derivative, cationic cellulose has becoming an attractive material. However, it remains challenging to produce cationic cellulose with high substitute degree. In this paper, we successfully increased the substitute degree of cationic cellulose by introducing ultrasonic treatment, which efficiently breaks hydrogen bonds of the chemical structure of cationic cellulose. Properties of cationic cellulose were studied by scanning electron spectroscope (SEM), contact angle, X-ray diffraction (XRD) and thermogravimetric analysis (TGA). Experimental results show that the cationic cellulose has rougher surface and lower crystallinity degree as compared to the original sample. TGA analysis verifies that the thermostability of CLC decreases after the cationic modification. The residual of the cationic cellulose (25 wt%) after pyrolysis increases significantly as compared to that of the original cellulose (15 wt%). [ABSTRACT FROM AUTHOR]

Potato peel waste (PW) is a starch containing biomaterial produced in large amounts by food processing industry. In this work, the treatment of PW by alkaline hydrolysis and cationization in the water phase is reported. In order to improve the cationization of starch, PW was hydrolyzed by heating with alkaline (NaOH) ethanol solution (80%) in a water bath. The impact of variable molar ratios of anhydroglucose unit (AGU):NaOH, heating temperatures and times was studied on the degradation of starch and the molecular size distribution of the product. The hydrolyzed PW was cationized subsequently in water by using glycidyltrimethylammonium chloride and catalyzed by NaOH under microwave irradiation or in an oil bath. The impact of the various reaction conditions on the cationization and degree of substitution of starch was studied. The degree of substitution of the cationized starch varied in the range of 0–0.35. [ABSTRACT FROM AUTHOR]

In this work, Micro-fibrillated Cellulose (MFC) was cationically modified by quaternary ammonium groups with different chemical structures aiming to improve the sorption capacity to bile acid. The in-vitro bile acid sorption was performed by investigating various factors, such as quaternary ammonium group content and length of its alkyl substituent of the modified cationic MFC (CMFC), ionic strength, initial concentration and hydrophobicity of bile acid. The results showed that the sorption behavior of the modified CMFC was strongly influenced by the quaternary ammonium group content and the lengths of its alkyl substituent, the sorption capacity for the modified CMFC with a C 18 alkyl substituent, was approximately 50% of that of Cholestyramine. The experimental isotherm results were well fitted into the Temkin model. The effect of salts in the solution was smaller for the bile acid sorption onto the hydrophobic CMFC than the CMFC. It was also found that the binding capacity of CMFC was higher for more hydrophobic deoxycholate in comparison with cholate. [ABSTRACT FROM AUTHOR]