The Effect of Antiozonants on the Reaction of Dyes with Ozone. 1 — Mechanism of Antiozonant Action

The effect of antiozonants on the reaction between dyes and ozone has been investigated. The antiozonant effect was found to increase the greater the agent's reactivity with ozone. The antiozonant also reacted with radicals produced by the homolytic cleavage of the substrate-ozone adducts. The effect of the added antiozonant generally increased in the order 2, 6-di-t-butylphenol < α-tocopheral, dibutylthiourea < N-isopropyl-N′-phenyl-p-phenylendiamine ? nickel dibutyl-dithiocarbamate.     

Water‐soluble cationic polymers and their polymer–metal complexes with biocidal activity: A genotoxicity study

Water‐soluble polyelectrolytes containing ammonium and sulfonic groups, their polymer–Ag(I) complexes, and silver nitrate were investigated as bactericidal compounds for Staphylococcus aureus (Collection No. ATCC 28922) and Escherichia coli (Collection No. 6538P) according to the National Committee for Clinical Laboratory Standards (NCCL) method. All the compounds, except Ag(I), showed bactericidal activity only for S. aureus. Ag(I) showed high bactericidal activity for both bacteria. No important effect of the molecular weight or macromolecular size on the maximum bactericidal concentration value was observed. The genotoxicity was studied using the rec assay. None of the macromolecular compounds showed genotoxicity, except silver ions, whose value was borderline. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 452–457, 2003     

Carrier‐bound methotrexate. I. Water‐soluble polyaspartamide–methotrexate conjugates with ester links in the polymer–drug spacer

The antifolate‐type anticancer drug methotrexate (MTX) has for many years, in numerous laboratories, been a “workhorse” drug for conjugation with natural and synthetic macromolecular carriers for the purpose of enhancing bioavailability and lowering toxic side effects. In the project here described the polymer–drug conjugation strategy is utilized for the preparation of water‐soluble polyaspartamide–methotrexate conjugates in which the drug is carrier‐anchored through short spacers containing ester groups as biofissionable links. To this end, polyaspartamide carriers 1, poly‐α,β‐D,L ‐N‐(2‐hydroxyethyl)aspartamide, and 2, poly‐α,β‐D,L ‐N‐[2‐(2‐hydroxyethoxy)ethyl]aspartamide, are treated with MTX in DMF solution in the presence of a carbodiimide coupling agent and 4‐(dimethylamino)pyridine catalyst. The molar MTX/OH feed ratios, 0.28 and lower, are chosen in these coupling reactions so as to provide conjugates featuring drug‐loading levels in the approximate range of 3–16 mol % MTX, roughly corresponding to 6–28% by mass. The water‐soluble product polymers are purified by aqueous dialysis, collected in the solid state by freeze‐drying, and structurally characterized by ¹H–NMR spectroscopy. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1844–1849, 2001     

Fibre–reactive Basic Dyes I–Polymethine Dyes Containing the N–Chloroacetyl Group

Several fibre–reactive basic (polymethine) dyes containing the N–chloroacetyl group have been prepared. They had better washing fastness on wool than their non–reactive analogues. Exhaustion figures were obtained in the usual way (colorimetrically) for all the dyes in Table 1 at the following pH: 2. 5, 3. 6, 4. 7, 5. 8, 6. 9 and 8. 4. However, these results were not in accord with visual assessments of the depths and it appears likely that some decomposition of the dyes takes place, in the presence of wool, particularly at higher pH values.     

Live‐Cell Imaging with Water‐Soluble Aminophenoxazinone Dyes Synthesised through Laccase Biocatalysis

Aminophenoxazinone dyes with variable water solubilities were assayed for the first time in a live‐cell imaging application. Among a library of ten sulfonylated chromophores, one compound gave excellent results as an endocytic marker, showing a precise subcellular distribution. The compound was compared to four commercial vital tracers, including Lucifer Yellow. The first laccase‐mediated regioselective synthesis of a diphosphorylated 2‐aminophenoxazinone dye was also described. This compound, water‐soluble at 10^?2 M , displayed modest fluorescence properties and the ability to complex Mg²⁺ and Ca²⁺ cations, therefore giving fluorescence quenching.     

Water‐soluble,antiyellowing polymeric fluorescence brighteners

In this study, a type of polymeric fluorescence brightener (PFB) with a triazine–stilbene structure was synthesized through a three‐step condensation reaction, and the performance of this PFB on antiyellowing was also investigated by the whiteness of paper coated with the as‐prepared PFB. Fourier transform infrared spectra revealed that the chlorine atom (·Cl) was substituted by a poly(vinyl alcohol) (PVA) group ([CH₂CHOH]_n). According to the UV aging experiment, the PFB not only enhanced the whiteness of the paper but also improved the anti‐UV aging properties [compared to those of VBL 4′‐double‐(6‐diethanolamine‐4‐sulfanilic acid‐1,3,5‐triazine‐2‐amino)‐stilbene‐2,2′‐disulfonic acid sodium, a type of commonly used fluorescent whitening agent as a light stabilizer and fluorescent brightening agent]. Moreover, the results of UV–visible spectra indicated that the substitution of PVA suppressed the isomerization of trans conformers to cis conformers under UV light irradiation; this was attributed to the big space steric hindrance of PVA in the as‐prepared samples being restricted the isomerization reaction. Meanwhile, the solubility of the as‐prepared sample was also improved because more hydroxyl groups were introduced into the PFB with the substitution of PVA. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45536.     

Carrier‐bound methotrexate. II. Water‐soluble polyaspartamide methotrexate conjugates with amide links in polymer–drug spacer

In Part I of this series, conjugation of methotrexate (MTX) to water‐soluble polyaspartamide carriers was accomplished through ester link formation between an MTX carboxyl group and a carrier‐attached hydroxyl function. Contrasting with that type of anchoring link, this project utilizes amide formation as the means of drug conjugation. This is achieved through condensation of one of the drug's carboxyl groups with a carrier‐attached primary amine function. Derived from polysuccinimide by a time‐proven nucleophilic ring‐opening process in the presence of aliphatic diamines, polyaspartamide‐type carriers 1–12 comprise subunits equipped with tert‐amine or hydroxyl side group terminals for hydrosolubilization and other subunits equipped with primary amine terminals as drug‐binding sites. MTX conjugation with these carriers is effected in aprotic solvent, the reaction being mediated by 2‐(1H‐benzotriazol‐1‐yl)‐1,1,3,3‐tetramethyluronium hexafluorophosphate. The water‐soluble conjugates are fractionated and purified by size exclusion chromatography and dialysis; they are isolated by freeze‐drying in typical yields of 40–65%. In the molar MTX/NH₂ feed ratios that are chosen (generally 1.2–1.3) and with the mole fractions of drug‐binding subunits restricted to 10 and 20%, drug loading in the resultant conjugates approximates 20–30% by mass. In follow‐on study, conjugates 1‐MTX–12‐MTX thus obtained will be screened in cell culture tests for antiproliferative activity against a number of human cancer lines. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3415–3424, 2006     

Water‐soluble and polymerizable thioxanthone photoinitiator containing imidazole

A novel free radical photoinitiator, 3‐allyl‐1‐[2‐hydroxy‐3‐(thioxanthen‐9‐one‐2‐yl)oxypropyl]imidazolium chloride ([AIPTX]Cl), is synthesized by the addition reaction of 2‐(2,3‐epoxy)propoxylthioxanthone (ETX) with a heterocyclic compound imidazole firstly, and the achieved intermediate 1‐[2‐hydroxy‐3‐(thioxanthen‐9‐one‐2‐yl)oxypropyl]imidazole (IPTX) is then reacted with allyl chloride. IPTX is chosen to evaluate the photoefficiency of [AIPTX]Cl. FTIR and ¹H‐NMR confirm the structures of [AIPTX]Cl and IPTX. UV‐Vis spectra of the two photoinitiators are similar and both exhibit the maximal absorption about 400 nm. Fluorescence spectra show [AIPTX]Cl/IMZ has slightly higher fluorescence intensity than IPTX system. Photopolymerization studies indicate that [AIPTX]Cl/IMZ is more efficient for the polymerization of water‐soluble monomer than IPTX. Moreover, due to its advantages of water solubility and polymerizability, [AIPTX]Cl is an environmental‐friendly photoinitiator and has potential for application in UV‐curing systems. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40659.     

Water‐soluble polymer and photocatalysis for arsenic removal

In this study, the photocatalytic oxidation of hazardous arsenite (As(III)) to arsenate (As(V)) and the sequential removal of arsenate from aqueous solution by liquid‐phase polymer‐based retention (LPR) were investigated. The photocatalytic oxidation of arsenite was performed using TiO₂ (P25 Degussa, Germany) under UV‐A light. The optimal photocatalytic conditions to oxidize 10 mg L^?1 of arsenite solution were achieved using a 0.5 g L^?1 of catalyst at a pH value of 2. The As(III) oxidation reached 100% after 30 min of illumination with UV‐A light. A water‐soluble polymer containing quaternary ammonium groups, poly(3‐acrylamidopropyl)trimethylammonium chloride (P(ClAPTA)), was used as an extracting reagent in the LPR process. To obtain the optimized conditions, the removal experiments were performed at various polymer : As(V) molar ratios using 10 mg L^?1 of arsenate solutions. After the oxidation of As(III) to As(V), the removal of arsenate by P(ClAPTA) was obtained in a 99% yield using a 20 : 1 polymer : As(V) molar ratio at a pH value of 9. The results demonstrate that the combination of these methods is highly useful for potential applications related to the treatment of wastewater contaminated with As(III). © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40871.     

Mechanism of Reaction of Proteins with Reactive Dyes IV—Reactivity of Wool with Chlorotriazine Dyes*

Chlorinated wool was dyed with a monochlorotriazine reactive dye under infinite dyebath conditions. The kinetics of dyeing conformed to a composite equation derived from the Danckwerts and Hill equations for diffusion into an infinite cylinder with surface saturation. The rate constants for the reaction between the dye and the fibre obtained from this equation agreed well with theoretical constants calculated from the reactivities of model compounds and data obtained from amino-acid analysis. The relative contributions of the individual types of reactive site to the total reactivity of wool are discussed.     

Water‐soluble photopolymers for rapid prototyping of cellular materials

Commercial light‐sensitive resins for Rapid Prototyping of cellular materials are often unsuitable for different molding techniques because removal of the mold uses thermal decomposition at temperatures of up to 600°C. In this study, a resin formulation based on water‐soluble polymers was developed and evaluated regarding its usability as sacrificial mold material. The base monomer dimethylacrylamide gave fast curing and excellent polymer solubility. Methacrylic acid was found to be a useful comonomer to improve mechanical strength and feature resolution. The latter criterion was also improved by adding poly(vinyl pyrrolidone) as filler and by using a hydrolytically cleavable crosslinking agent such as methacrylic acid anhydride. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2286–2298, 2005     

Mechanism of Reaction of Proteins with Reactive Dyes:III—Reactivity of Soluble Proteins with Chlorotriazine Dyes

The reactivities of ten soluble proteins with a monochlorotriazine reactive dye were measured under various conditions and compared with those of mixtures of simple model compounds representing the reactive groups of the proteins. Both sets of results agreed wellwith reactivity curves calculated from measurements of the individual model compounds. The mechanisms of the reactions between the dye and proteins are discussed with reference to the dyeing of wool and other proteinaceous fibres.     

Water‐soluble ionic polythiophenes for biological and analytical applications

Ionic polythiophenes are important conjugated polymers because of their excellent optical properties and water solubility. They are classified as cationic, anionic and zwitterionic conjugated polyelectrolytes. This review article describes concisely their biological and analytical applications. The specific detection of different negatively charged biomolecules such as DNA and adenosine triphosphate, anions like halides and toxic pseudo‐halide (CN ^?) and environmental pollutants, e.g. surfactants, is discussed. The conformational changes of cationic polythiophenes (CPTs ) induced by various analytes due to formation of ionic conjugates and the cooperative responses of all segments cause dominant signal amplification even in the presence of a small perturbation. In addition, reactive oxygen scavenging, antimicrobial photosensitizing and cell imaging applications of CPTs are documented. Use of anionic polythiophenes for sensing of protamine and cations like Cu²⁺ and Ca²⁺ is also discussed. Finally, sensing of DNA , peptides and surfactants by zwitterionic polythiophenes is included. The concluding part discusses future prospects. © 2016 Society of Chemical Industry     

Mechanism of Reaction of Proteins with Reactive Dyes:II—Reactivity of Simple Model Compounds with Chlorotriazine Dyes

The chemistry of the functional groups in wool is described and the selection of appropriate model compounds for them is discussed. The measurement of the reactivities of these model compounds and possible mechanisms of their reactions are discussed. The nucleophilic anion is the important species in the reaction of a chlorotriazine dye with the thiol group in cysteine or the hydroxyl and phenolic groups in serine, threonine and tyrosineresidues. The reaction of a chlorotriazine dye with the amino groups of lysine and the N-terminal amino acids, with the imidazole group of histidine and with the guanidinogroup of arginine takes place mainly with the unprotonated base. Evidence in support of these mechanisms is provided by an investigation of the reactions of the dye with aqueous ammonia and anhydrous liquid ammonia.     

Water‐soluble macromolecular co‐assemblies of star‐shaped polyelectrolytes

This mini‐review reports on complex macromolecular architectures (interpolyelectrolyte complexes) based on star‐shaped polyelectrolytes. These complexes can be prepared in aqueous media via electrostatically driven co‐assembly of star‐shaped polyions (a) with oppositely charged linear homopolyelectrolytes or (b) with oppositely charged double hydrophilic (ionic/non‐ionic) diblock copolymers. In case (a), the complexes can be water‐soluble if the charge of the star‐shaped macromolecule is only partially compensated by a linear polyion. In case (b), the complexes retain their solubility in aqueous media even under a full charge compensation of the polymeric components. In both cases, the complex macromolecular architectures based on star‐shaped polyelectrolytes are characterized by a distinct compartmentalized structure of a micellar (‘core–corona’) type with an insoluble core, which is assembled from coupled monomer units of the oppositely charged polymeric components, and a hydrophilic, either ionic or non‐ionic, corona. Copyright © 2012 Society of Chemical Industry     

Water–Polymer interactions in PVME hydrogels – Raman spectroscopy studies

Raman spectroscopy was used to investigate molecular interactions and structure of water in PVME hydrogels of various crosslinking degrees. Analysis of polymer ν(CH₃) and ν(CH₂) stretching vibrations has allowed to monitor the changes of hydrophilic and hydrophobic polymer–water interactions in a course of water deswelling and volume phase transition. Formation of water–polymer hydrogen bonds has appeared to influence directly supramolecular structure of the absorbed water. It was found that the polymer network density determines an availability of the hydrophilic sites to water molecules and also influences the kinetics of volume phase transition of the hydrogels. Activation energy of the volume phase transition in the investigated systems was estimated to be ca.88 kJ/mol.     

Mass–spectra Studies of Disperse Dyes

The mass spectra of benzo(k, l)thioxanthene–3, 4–dicarboxylic anhydride and of several derived imides, dyes for synthetic–polymer fibres, are reported. Principal fragmentation trends are described and fragments which may be used in the characterisation of these dyes are described.     

Modeling of Ozone Reaction with Benzaldehyde Incorporating Ozone Decomposition in Aqueous Solutions

Ozonation of benzaldehyde in its aqueous solutions based on mechanistic approach and incorporating ozone decomposition model is presented in this work. As the basis the modified and extended HSB model of ozone decomposition with phosphates and carbonates reactions included has been applied. It was then tuned with the literature data and the results of our own measurements on ozone decay in aqueous solutions. The model was extended to model benzaldehyde oxidation reactions in the aqueous solutions. Model predictions compare favorably against experimental data obtained in the range of pH 2.3 to 8 with or without radical scavenger (t-butanol).