Controlled Synthesis, Dye-fixing Performance and Dye-fixing Mechanisms on Cotton Fabric of Novel Reactive Cationic Copolymers of N,N-Diallyl-3-hydroxy-azetidinium Chloride and Dimethyldiallylammonium Chloride (P(DHAC-DMDAAC)s)

2012 ◽  
Vol 65 (4) ◽  
pp. 351 ◽  
Author(s):  
Yikai Yu ◽  
Yuejun Zhang
Keyword(s):  
Cotton Fabric ◽  
Raw Materials ◽  
Strong Interactions ◽  
Hydroxyl Groups ◽  
Anionic Dyes ◽  
Ether Linkage ◽  
Covalent Bonds ◽  
Produce Water ◽  
Molar Ratios ◽  
Cationic Copolymers

First, a series of novel reactive cationic copolymers (P(DHAC-DMDAAC)s) of N,N-diallyl-3-hydroxy-azetidinium chloride (DHAC) and dimethyldiallylammonium chloride (DMDAAC) with controlled structures and controlled molecular weights characterized by intrinsic viscosities of 0.11–0.89 dL g–1 were successfully synthesized by varying the molar ratios of raw materials DHAC to DMDAAC from 1 : 99 to 20 : 80 and increasing initial monomer concentrations from 35 to 55 % with a decrease of initiator amount from 7 to 3 % during polymerization. Second, it was found that the dye-fixing performance of P(DHAC-DMDAAC)s could be further increased by incorporation of 7 % molar content of DHAC units into the main chains of controlled-molecular-weight poly(dimethyldiallylammonium chloride) (PDMDAAC) dye fixatives, and their best dye-fixing performance was better than all the widely used commercial polycationic dye fixatives, indicating that the obtained P(DHAC-DMDAAC)s could be novel useful reactive polycationic dye fixatives for cotton fabric. Last, it was found from studies on dye-fixing mechanisms on cotton fabric by modern analysis techniques that the reactive units (DHAC) of the obtained P(DHAC-DMDAAC)s could form covalent bonds with the hydroxyl groups of cotton (cellulose) to give an ether linkage, resulting in strong interactions of P(DHAC-DMDAAC)s with the cotton fabric as well as the electrostatic forces between the anionic dyes and the basic cationic groups in the polymers to produce water-insoluble colour lakes, for the development of the dye fastness on cotton fabric.

scholarly journals Roles of Novel Reactive Cationic Copolymers of 3-Chloro-2-hydroxypropylmethyldiallylammonium Chloride and Dimethyldiallylammonium Chloride in Fixing Anionic Dyes on Cotton Fabric

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Yikai Yu ◽  
Yuejun Zhang
Keyword(s):  
Ir Spectra ◽  
Cotton Fabric ◽  
Sem Analysis ◽  
Hydroxyl Groups ◽  
Water Color ◽  
Anionic Dyes ◽  
Ether Linkage ◽  
Cotton Sample ◽  
Ft Ir ◽  
Cationic Copolymers

The roles of novel reactive cationic copolymers (P(CMDA-DMDAAC)s) of 3-chloro-2-hydroxypropylmethyldiallylammonium chloride (CMDA) and dimethyldiallylammonium chloride (DMDAAC) in fixing anionic dyes on cotton fabric were studied by modern instrumental analysis technologies such as FT-IR spectra and SEM analysis, to achieve the new theoretical guides for the wide applications of those dye fixatives. The FT-IR spectra of the obtained insoluble-water color lakes verified that they could be formed from the electrostatic interactions of the P(CMDA-DMDAAC)s with anionic dyes, which were further confirmed by the FT-IR analysis of the anionic dyes on dyeing cotton sample fixed by P(CMDA-DMDAAC)s. The FT-IR spectra of cotton samples fixed by P(CMDA-DMDAAC)s showed the absorptions of P(CMDA-DMDAAC)s and the signs similar to the formation of new ether linkage on cotton fabric even after being repeatedly washed, which were further confirmed by the SEM analysis of the fixed dyeing cotton samples. Thus, the reactive units (CMDA) of the obtained P(CMDA-DMDAAC)s could be expected to bring about the covalent bonds with the hydroxyl groups of cotton (cellulose) to form an ether linkage when fixing, resulting in the stronger interactions of P(CMDA-DMDAAC)s with cotton fabric, as well as their electrostatic forces with anionic dyes to produce the insoluble-water color lakes, for the development of fastness of anionic dyes on cotton fabric.

scholarly journals Dye-fixing performances of slightly crosslinked poly(dimethyldiallylammonium chlorides) on cotton fabric

2013 ◽  
Vol 32 (1) ◽  
pp. 125
Author(s):  
Yikai Yu ◽  
Yuejun Zhang
Keyword(s):  
Cotton Fabric ◽  
Cotton Fabrics ◽  
Brilliant Blue ◽  
Cross Linking ◽  
Molar Content ◽  
Anionic Dyes ◽  
Colour Fastness ◽  
Molecular Weights ◽  
Molar Ratios ◽  
Better Than

Slightly cross-linked poly (dimethyldiallylammonium chlorides) (PDMDAACs) with different molecular weights characterized by intrinsic viscosities and structures were prepared as copolymers of triallylmethylammonium chloride (TAMAC), a cross-linking monomer, with dimethyldiallylammonium chloride (DMDAAC). They were then studied as novel, promising reactive polycationic dye-fixatives on cotton fabric. A series of slightly cross-linked PDMDAACs with controlled 1%–5% molar ratios of crosslinking units (TAMAC units) in the main chains and intrinsic viscosities of 0.04~0.86 dL/g were used to treat cotton fabrics dyed with anionic dyes such as Reactive Scarlet 3BS and Reactive Brilliant Blue KNR. Their dye-fixing performance, evaluated by dry rubbing fastness, wet rubbing fastness, colour fastness to soaping, and white fabric staining, were examined. The results showed their dye-fixing performances were affected by their intrinsic viscosities and the molar content of TAMAC units; slightly cross-linked PDMDAACs with intrinsic viscosities of 0.16-0.30 dL/g and 1% TAMAC exhibited the best dye-fixing performances and were better than all members of a group of selected widely-used commercial polycationic dye-fixatives. This was attributed to their plane-like structures and the nice balance between structure and intrinsic viscosities. Thus it was confirmed that the selected slightly cross-linked PDMDAACs can be used as novel dye-fixatives on cotton fabric.

QM/MM Simulations of Organic Phosphorus Adsorption at the Diaspore-Water Interface

2019 ◽  
Author(s):  
Prasanth Babu Ganta ◽  
Oliver Kühn ◽  
Ashour Ahmed
Keyword(s):  
Interaction Energy ◽  
Dynamics Simulation ◽  
Water Molecules ◽  
Hydroxyl Groups ◽  
Water Interface ◽  
Mineral Surfaces ◽  
Soil Mineral ◽  
Phosphorus Adsorption ◽  
Covalent Bonds ◽  
Binding Mechanisms

The phosphorus (P) immobilization and thus its availability for plants are mainly affected by the strong interaction of phosphates with soil components especially soil mineral surfaces. Related reactions have been studied extensively via sorption experiments especially by carrying out adsorption of ortho-phosphate onto Fe-oxide surfaces. But a molecular-level understanding for the P-binding mechanisms at the mineral-water interface is still lacking, especially for forest eco-systems. Therefore, the current contribution provides an investigation of the molecular binding mechanisms for two abundant phosphates in forest soils, inositol hexaphosphate (IHP) and glycerolphosphate (GP), at the diaspore mineral surface. Here a hybrid electrostatic embedding quantum mechanics/molecular mechanics (QM/MM) based molecular dynamics simulation has been applied to explore the diaspore-IHP/GP-water interactions. The results provide evidence for the formation of different P-diaspore binding motifs involving monodentate (M) and bidentate (B) for GP and two (2M) as well as three (3M) monodentate for IHP. The interaction energy results indicated the abundance of the GP B motif compared to the M one. The IHP 3M motif has a higher total interaction energy compared to its 2M motif, but exhibits a lower interaction energy per bond. Compared to GP, IHP exhibited stronger interaction with the surface as well as with water. Water was found to play an important role in controlling these diaspore-IHP/GP-water interactions. The interfacial water molecules form moderately strong H-bonds (HBs) with GP and IHP as well as with the diaspore surface. For all the diaspore-IHP/GP-water complexes, the interaction of water with diaspore exceeds that with the studied phosphates. Furthermore, some water molecules form covalent bonds with diaspore Al atoms while others dissociate at the surface to protons and hydroxyl groups leading to proton transfer processes. Finally, the current results confirm previous experimental conclusions indicating the importance of the number of phosphate groups, HBs, and proton transfers in controlling the P-binding at soil mineral surfaces.

scholarly journals Modification of cotton fabrics with 2-diethylaminoethyl chloride for salt-free dyeing with anionic dyes

Cellulose ◽  
2021 ◽  
Author(s):  
Peixin Tang ◽  
Leilah-Marie E. Lockett ◽  
Mengxiao Zhang ◽  
Gang Sun
Keyword(s):  
Electrostatic Interactions ◽  
Light Exposure ◽  
Dye Adsorption ◽  
Cost Effective ◽  
Cotton Fabrics ◽  
Cotton Cellulose ◽  
Hydroxyl Groups ◽  
Anionic Dyes ◽  
Free System ◽  
Untreated Cotton

AbstractA chemical modification of cotton fabrics by 2-diethylaminoethyl chloride (DEAE-Cl) was achieved, and the resulted cotton fabrics demonstrated salt-free dyeing properties with anionic dyes. Nucleophilic property of hydroxyl groups in cotton cellulose was enhanced under alkaline conditions and could react with DEAE-Cl, a chemical possessing both nucleophilic and electrophilic sites. The monolayered DEAE-grafted cotton cellulose could further react with DEAE-Cl to form multiple cationic quaternary ammonium salts (denoted as DEAE@Cotton), which are highly interactive with anionic dye molecules. The strong electrostatic interactions between the DEAE@Cotton and the dyes eliminated the use of inorganic salts in cotton dyeing process. The chemical structure and property of DEAE@Cotton were characterized and compared with untreated cotton. The DEAE@Cotton can be dyed in a salt-free system, and the dye exhaustion was faster than the conventional dyeing method due to the robust electrostatic interactions of the fabrics with anionic dyes. The dyed fabrics demonstrated outstanding color fastness under repeated washing, light exposure, and crocking. The dye adsorption process on DEAE@Cotton follows Langmuir isotherm model (R2 = 0.9667). The mechanism of enhanced dyeability was experimentally proved by treating the fabric with other anionic dyes in a salt-free system, proving the process to be environmentally friendly and cost-effective. Graphic abstract

scholarly journals Chlorine-Resistant Hollow Nanosphere-Like VOx/CeO2 Catalysts for Highly Selective and Stable Destruction of 1,2-Dichloroethane: Byproduct Inhibition and Reaction Mechanism

Processes ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 119
Author(s):  
Yu Huang ◽  
Shiyue Fang ◽  
Mingjiao Tian ◽  
Zeyu Jiang ◽  
Yani Wu ◽  
...  
Keyword(s):  
Oxygen Vacancies ◽  
Acid Sites ◽  
Strong Interactions ◽  
Hollow Nanosphere ◽  
Efficient Removal ◽  
Chlorinated Volatile Organic Compounds ◽  
Molar Ratios ◽  
Volatile Organic ◽  
Redox Ability ◽  
Species Mobility

Developing economical and robust catalysts for the highly selective and stable destruction of chlorinated volatile organic compounds (CVOCs) is a great challenge. Here, hollow nanosphere-like VOx/CeO2 catalysts with different V/Ce molar ratios were fabricated and adopted for the destruction of1,2–dichloroethane (1,2–DCE). The V0.05Ce catalyst possessed superior catalytic activity, reaction selectivity, and chlorine resistance owing to a large number of oxygen vacancies, excellent low-temperature redox ability, and chemically adsorbed oxygen (O− and O2−) species mobility. Typical chlorinated byproducts (CHCl3, CCl4, C2HCl3, and C2H3Cl3) derived from the cleavage of C–Cl and C–C bonds of 1,2–DCE were detected, which could be effectively inhibited by the abundant acid sites and the strong interactions of VOx species with CeO2. The presence of water vapor benefited the activation and deep destruction of 1,2–DCE over V0.05Ce owing to the efficient removal of Cl species from the catalyst surface.

scholarly journals WOOD COMPONENTS AS SOURCES OF PENTO-CONTAINING RAW MATERIALS FOR SYNTHESIS OF USEFUL COMPOUNDS, PRODUCTS AND REAGENTS

2021 ◽  
Vol 64 (3) ◽  
pp. 107-115
Author(s):  
Irina A. Chetvertneva ◽  
Oleg Kh. Karimov ◽  
Galina A. Teptereva ◽  
Natalia S. Tivas ◽  
Eldar M. Movsumzade ◽  
...  
Keyword(s):  
Raw Materials ◽  
Condensation Reaction ◽  
Agricultural Waste ◽  
Monomer Unit ◽  
Paper Industry ◽  
Raw Material ◽  
Chemical Transformations ◽  
Covalent Bonds ◽  
Industry Waste ◽  
Wood Processing

The paper considers the main components and products of wood processing, agricultural waste, pulp and paper industry waste and qualifies them as sources of pentose-containing resource-renewable domestic raw materials. The article describes in detail the structural components of wood as a natural polymer, which contains aromatic and carbohydrate parts. It is noted that these poly-mers are promising as raw materials for the production of useful chemical products. The role of lignin, cellolose and hemicellulose in the design of mechanical and structural properties of wood is considered. The article considers the features of the sulfonation reactions of the lignin monomer unit depending on the pH of the medium: acidic, neutral and alkaline. There are three main reac-tions that occur simultaneously with lignin in the process of wood delignification during sulfite cooking, such as the sulfonation reaction, the hydrolytic destruction reaction, and the condensation reaction. It is shown that the lignin-hemicellulose matrix contains three types of interconnected mesh structures: the lignin itself; a network of covalent bonds of lignin with hemicelluloses, and a network whose structure is obtained due to the hydrogen bond and the forces of the physical inter-action of lignin and hemicelluloses. The features of chemical transformations of the monomeric aromatic link of lignosulfonate – phenylpropane unit in the processes of wood delignification, the main chemical reactions of wood raw material delignification under the conditions of sulfite and neutral-sulfite brews are shown. The method of quantitative determination of monosaccharides in the composition of the carbohydrate part is proposed.

scholarly journals Hydrophilic Polyhedral Oligomeric Silsesquioxane, POSS(OH)32, as a Complexing Nanocarrier for Doxorubicin and Daunorubicin

Materials ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 5512 ◽  
Author(s):  
Kinga Piorecka ◽  
Anna Janaszewska ◽  
Marta Majkowska ◽  
Monika Marcinkowska ◽  
Jan Kurjata ◽  
...  
Keyword(s):  
Drug Carrier ◽  
Correlation Spectroscopy ◽  
Hydroxyl Group ◽  
Cancer Drug ◽  
Breast Adenocarcinoma ◽  
Hydroxyl Groups ◽  
Polyhedral Oligomeric Silsesquioxanes ◽  
Molar Ratios ◽  
Anti Cancer ◽  
Mcf 7

A novel strategy, recently developed by us, to use polyhedral oligomeric silsesquioxanes (POSS) as an anti-cancer drug carrier is presented. Anthracycline:POSS complexes were prepared by simple co-addition of doxorubicin (DOX) or daunorubicin (DAU) with hydrophilic POSS(OH)32. Co-delivery of POSS and anthracyclines led to higher anti-cancer activity towards HeLa (cervical cancer endothelial) and MCF-7 (human breast adenocarcinoma) cell lines. The obtained supramolecular hybrid complexes were characterised by nuclear magnetic resonance (NMR) spectroscopy (nuclear Overhauser effect spectroscopy [NOESY] and homonuclear correlation spectroscopy [COSY]), Fourier transform infrared spectroscopy (FTIR), and dynamic light scattering (DLS). The two-dimensional (2D) NOESY spectra of the complexes showed the cross-correlation peaks for hydroxyl groups of POSS (~4.3–4.8 ppm) with OH groups of DOX and DAU. FTIR showed that hydroxyl group of POSS can interact with amine and hydroxyl groups of DOX and DAU. The viability of HeLa and MCF-7 was analysed with the MTT assay to evaluate the cytotoxicity of free DOX and DAU and the relevant complexes with POSS at different molar ratios. At a low DOX concentration (2.5 µM), for molar ratios 1:1, 1:4, and 1:8 (POSS:DOX), the complexes showed two and three times higher cytotoxicity towards HeLa and MCF-7 cells, respectively, than DOX itself after both 24- and 48-h incubation. The 1 µM concentration for a 1:4 POSS:DOX molecular ratio and the 2.5 µM concentration for all complexes were more toxic towards MCF-7 cells than free DOX after 48-h incubation. In the case of POSS:DAU complexes, there was higher toxicity than that of free drug after 48-h incubation. It can be concluded that the formation of non-covalent complexes increases toxicity of anthracycline drugs towards Hela and MCF-7 cells. The novel complexes are inexpensive to prepare and more effective than free drugs at low systemic toxicity.

scholarly journals The Nature of Triel Bonds, a Case of B and Al Centres Bonded with Electron Rich Sites

Molecules ◽  
2020 ◽  
Vol 25 (11) ◽  
pp. 2703 ◽  
Author(s):  
Sławomir J. Grabowski
Keyword(s):  
Lewis Acids ◽  
Weak Interactions ◽  
Lewis Base ◽  
Basis Set ◽  
Strong Interactions ◽  
Orbital Method ◽  
Covalent Bonds ◽  
Moller Plesset ◽  
Intermolecular Distances ◽  
Base Units

The second-order Møller–Plesset perturbation theory calculations with the aug-cc-pVTZ basis set were performed on complexes of triel species: BCl3, BH3, AlCl3, and AlH3 acting as Lewis acids through the B or Al centre with Lewis base units: NCH, N2, NH3, and Cl− anion. These complexes are linked by triel bonds: B/Al⋅⋅⋅N or B/Al⋅⋅⋅Cl. The Quantum Theory of ´Atoms in Molecules´ approach, Natural Bond Orbital method, and the decomposition of energy of interaction were applied to characterise the latter links. The majority of complexes are connected through strong interactions possessing features of covalent bonds and characterised by short intermolecular distances, often below 2 Å. The BCl3⋅⋅⋅N2 complex is linked by a weak interaction corresponding to the B⋅⋅⋅N distance of ~3 Å. For the BCl3⋅⋅⋅NCH complex, two configurations corresponding to local energetic minima are observed, one characterised by a short B⋅⋅⋅N distance and a strong interaction and another one characterised by a longer B⋅⋅⋅N distance and a weak triel bond. The tetrahedral triel structure is observed for complexes linked by strong triel bonds, while, for complexes connected by weak interactions, the structure is close to the trigonal pyramid, particularly observed for the BCl3⋅⋅⋅N2 complex.

scholarly journals Modification of softwood kraft pulp fibres using hydrogen peroxide at acidic conditions

Cellulose ◽  
2020 ◽  
Vol 27 (12) ◽  
pp. 7191-7202
Author(s):  
Axel Martinsson ◽  
Merima Hasani ◽  
Antje Potthast ◽  
Hans Theliander
Keyword(s):  
Hydrogen Peroxide ◽  
Residence Time ◽  
Kraft Pulp ◽  
Hydroxyl Groups ◽  
Carbonyl Groups ◽  
Wet Strength ◽  
Covalent Bonds ◽  
Softwood Kraft Pulp ◽  
Pulp Fibres ◽  
Acidic Conditions

Abstract The aim of this work was to provide softwood kraft pulp fibres with new functionalities by the introduction of carbonyl groups. Carbonyl groups are known to affect properties such as wet strength through the formation of covalent bonds, i.e. hemiacetals. The method developed involves oxidation using hydrogen peroxide at mildly acidic conditions. It was found that the carbonyl group content increased with both increasing temperature and residence time when oxidized at acidic conditions. The number of carboxylic groups, however, remained approximately constant. There was virtually no increase in carbonyl groups when oxidation was performed at alkaline conditions. The maximum increase in carbonyl groups was found at a residence time of 90 min, a reaction temperature of 85 °C and a pH of 4. These conditions resulted in an increase in carbonyl groups from 30 to 122 µmol/g. When formed into a sheet, the pulp oxidized at acidic conditions proved to maintain its structural integrity at aqueous conditions. This indicates the formation of hemiacetal bonds between the introduced carbonyl groups and the hydroxyl groups on the carbohydrate chains. Thus, a possible application for the method could be fibre modification during the final bleaching stage of softwood kraft pulp, where the wet strength of the pulp could be increased.

Cyclic hydroxycarboxylic acids. III. Tosylation studies on Mono- and Di-hydroxycyclopentanecarboxylates and Mono- and Di-hydroxyprolines

1977 ◽  
Vol 30 (1) ◽  
pp. 131 ◽  
Author(s):  
RP Philp ◽  
AV Robertson
Keyword(s):  
Free Amino ◽  
Heterogeneous System ◽  
Methyl Esters ◽  
Hydroxyl Groups ◽  
Large Excess ◽  
Molar Ratios ◽  
Tosyl Chloride ◽  
Hydroxycarboxylic Acids ◽  
Hydroxy Proline ◽  
Cis And Trans

A large excess of reagent is needed for satisfactory ditosylation of methyl c-2,t-3- and t-2,c-3-di-hydroxycyclopentane-r-1-carboxylates using tosyl chloride-pyridine at 5° overnight. With less reagent, mixtures are produced from which one monotosyl derivative of the t-2,c- 3-series was isolated and its structure proved. By contrast, the methyl cis- and trans-2-hydroxycyclopentanecarboxylates readily tosylate with normal molar ratios of reagent. In the proline series ditosylation of 2,3-trans- 3,4-cis-3,4-dihydroxy-N-tosylproline methyl ester occurs normally in tosyl chloride-pyridine, and so does tosylation of both cis- and trans-4-hydroxy-N-tosylproline methyl esters. On the other hand tosylation of the 3-hydroxy counterparts is very slow, although acetylation of these 3-hydroxyl groups proceeds normally. The O-tosylation results are striking for the lack of pattern. A comparison is also made of O-tosylation accompanying N-tosylation of the free amino acids cis- and trans-3-hydroxy-proline, cis- and trans- 4- hydroxyproline, and the two cis-glycols of 3,4-dihydroxyproline in the heterogeneous system tosyl chloride-ether-aqueous NaOH. Significant O- tosylation occurs in some cases but not in others. This correlation permits assignment of structure to a mono-O-tosyl derivative of a 3,4- dihydroxy-N-tosylproline obtained previously by us.

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