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The purpose of this paper is to describe how lignosulphonate modified ketone formaldehyde resins containing functional groups such as hydroxyl, carbonyl, phenol, were produced via in situ modification of ketone/formaldehyde resins. Cyclohexanone‐formaldehyde (CF‐R), acetophenone‐formaldehyde (AF‐R) and methyl ethyl ketone‐formaldehyde (MEKFR) resins were in situ modified with lignosulphonate in the presence of sodium hydroxide. The paper reports the synthesis of lignosulphonate‐modified resins with a one step method of in situ modification of ketonic resin. The roles of the types of the ketone, lignosulphonate concentration, the solubility, molecular weight and thermal properties of the product were investigated.

Ketone, formalin (37 per cent aqueous solution), lignosulphonate were mixed and 20 per cent aqueous NaOH solution was added to produce the resin.

There was improvement of the properties of the lignosulphonate modified ketonic resins produced from waste black liquor. The lignosulphonate modified ketone‐formaldehyde resins were soluble in common organic solvents.

The reaction mixture must be stirred continuously. Subsequently, 37 per cent formalin was added dropwise in total while refluxing. The amount of aqueous NaOH solution is limited since the formed resin may become insoluble in common organic solvents. The water was removed from MEKFR, successively by evaporating with rotary evaporator.

This study provides the application of ketonic resins. The modified ketonic resins containing lignosulphonate groups may also promote the adhesive strength of a coating. The cell walls of various cell types of plants, for example, wood fibres, vessels, and tracheid, have lignin as an important constituent. It constitutes 20‐30 per cent of the weight of wood.

Lignosulphonate modified ketonic resins have been synthesized in the presence of a base catalyst. These resins have higher Tg or Tm values and molecular weight than CFR and AFR alone and also have thermoset property. Environmental and ecological concerns have increased the attention paid by the chemical industry to renewable raw materials.

SOLVENT DEWAXING OF LUBRICATING oils found its first commercial application in 1927 when Indian Refining Company started its original acetone‐benzene dewaxing operation. Since that time, solvent dewaxing has wholly superseded the classical cold pressing methods in new installations. Of 171,165 bbls/doz. lube oil produced in the United States in 1951, some 60% was of the solvent extraction type and 40% of the older conventional type. By 1954, solvent extraction's share had risen to an estimated 75% of all dewaxing operations.

Epoxy‐resin‐based paints generally offer very good corrosion‐protective properties and are widely used in harsh environments such as the sea. They are two‐pack systems, the curing agent normally used being polyamines or polyamides. Such systems find extensive use on structures exposed to dry conditions. When substrates lie under water or are constantly exposed to the wet, the above system is impracticable due to poor adhesion. For these environments, the curing agent has to be modified, and in such circumstances ketimines have been found to work. Many amines and ketones are used to obtain ketimines. The ketimine in contact with water hydrolyses, releasing a free amine, which in turn reacts with the epoxy resin and so curing takes place in situ. Reports on a study of effective ketimines in various coating systems.

The purpose of this paper is to produce non-conductive copolymers of N-vinyl carbazole (NVCz) and methyl ethyl ketone formaldehyde resin (MEKFR) by the electroinduced Ce (IV) polymerization method and the electrochemical oxidization of the formed copolymer to produce their conductive green form. The non-conductive and conductive copolymers were characterized by using Fourier transform infrared, solid-state conductivity and spectroelectrochemical, chronoamperometric, cyclovoltammetric and electrochemical impedance spectroscopic measurements.

The chronoamperometric electropolymerization of white, insulator form of the copolymer of NVCz and MEKFR (copolymer 1) on to Pt electrode was carried out and the green coloured film of the MEKFR-ox-NVCz copolymer (copolymer 11) was produced in the doped and conductive form. All reactions were performed in dichloromethane containing 0.1 M B_U4NClO₄. Copolymer 11 films obtained on the surface of the working electrode were removed and washed in acetonitrile and dried at room temperature before characterization. The results were compared with the copolymer obtained by electrochemical oxidation of MEKF-R and NVCz (copolymer 2).

The insulating copolymer of NVCz and MEKFR (copolymer 1) was produced by the electroinduced Ce (IV) polymerization method and converted into the conductive form electrochemically on the surface of the Pt electrode (copolymer 11). The polymers were characterized by electrochemical, spectrophotometric and conductivity measurements. The ionization potentials, optical band gap, peak potentials Ep, doping degree and specific capacitance of the copolymer 11 were obtained. The conductivity of the copolymer 11 is lower than the PNVCz and higher than the copolymer obtained by electrochemical oxidation of MEKF-R and NVCz (copolymer 2). The copolymer 11 has a lower onset potential than PNVCz and the copolymer 1 and slightly higher band gap than PNVCz. The capacitive behaviours of the copolymer 11 were very close to PNVCz.

This study focuses on obtaining a green and conductive form of the copolymer of NVCz and MEKFR with the electrochemical method by using a white and insulator form of the same copolymer.

This work provides technical information for the synthesis of conducting copolymer of NVCz and MEKFR.

These copolymers may be in the field of PNVCz applications such as photoconductivity and corrosion inhibition.

Electroinduced Ce (IV) MEKFR redox system was applied for the polymerization of NVCz monomer to produce the copolymer 1. The conductive copolymer 11 was synthesized through electrochemical oxidative coupling of the carbazole groups of the copolymer 1.

This paper aims to improve some properties of poly (methyl methacrylate) by copolymerization with butyl acrylate (BA) monomer along with the incorporation of the stable and economical synthesized silicone-containing monomer hexamethyldisilazanomethacryloxyphenyl ketone (HDMK) into the copolymer matrix.

For this target solution copolymerization of methyl methacrylate (MMA), BA and HDMK were carried out using a 250 mL four-necked round-bottom flask. Before solution polymerization start-up, the reaction vessel was first charged with 34.8 mL toluene and heated to 170 °C with stirring and reflux cooling. A monomer mixture of 25.86 g (260 mmol) MMA, 26.40 g (200 mmol) BA, 3.00 g (8.60 mmol) HDMK and 0.45 g (2.00 mmol) dibenzoyl peroxide was added continuously from the dropping funnel over a period of 4 h.

The HDMK was successfully synthesized and the water resistance of acrylic resins was improved because of the existence of HDMK.

The materials that were used in this research paper had a reasonably low cost. Also, the procedures for synthesis of monomers and polymers were extremely easy because there was no need for high pressure or temperature and no dangerous solvents were used.

The acrylic resin that contained HDMK was used to synthesis a white architectural paint for exterior coating. Examining the paint characteristics has shown acceptable washing and abrasion resistance, good brushing, excellent storage stability and great surface coating.

HDMK was synthesized for the first time.

The purpose of this paper was to study the color change kinetics of lac dye in response to aldehydes, carbon dioxide and other food spoilage metabolites for its potential application in intelligent food packaging.

UV–Vis spectroscopy was used to study the color change of dye solution. Ratio of absorbance of dye solution at 528 nm (peak of ionized form) to absorbance at 488 nm (peak of unionized form) was used to study the color change. Color change kinetics was studied in terms of change in absorbance ratio (A₅₂₈/A₄₈₈) with time using zero and first-order reaction kinetics. Lac dye-based indicator was prepared to validate the result of study for monitoring quality of strawberries.

Lac dye was orange-red in acidic medium and purple in alkaline medium. Color change of dye in response to benzaldehyde followed zero-order reaction kinetics, whereas for carbon dioxide first-order model was found best. No color change of dye solution was observed for alcohols, ketones and sulfur compounds. In the validation part, the color of the indicator label changed from purple to orange when the strawberries spoiled.

The study expands application area for lac dye as sensing reagent in intelligent food packaging for spoilage or ripeness detection of fruits and vegetables.

The purpose of this paper is to obtain a conductive polymer by using a fluorescence comonomer which is an insulator. In this study, methyl ethyl ketone formaldehyde resin (MEKFR) modified with carbazole‐9‐carbonyl chloride (CzCl) was synthesised via hydroxyl groups of MEKFR. Electrochemical polymerisation of Cz‐MEKFR comonomer was carried out potentiostatically and a green, conductive polymer P(Cz‐MEKFR) was obtained. The advantages of obtaining alternative structure of P(Cz‐MEKFR) to the random copolymer were reported.

Cz‐MEKFR comonomer was synthesised by the esterification reaction of CzCl and hydroxyl groups of MEKFR. Then, for the electrochemical polymerisation, potentiodynamic electrodeposition of Cz‐MEKFR comonomer in dichloromethane on to Pt was carried out. Electrochemical activities of polymers were tested by electrochemical methods (i.e. polarization curves and cyclovoltammetry). UV‐visible, NMR, polarization curves, cyclovoltammetric, solid‐state conductivity measurements and in situ spectroelectrochemical methods were performed for the characterization of polymers.

Carbazole‐9‐carbonyl chloride(CzCl) modified MEKFR was synthesised. This new carbazole‐modified resin (Cz‐MEKFR comonomer) has fluorescence property. The ionization potentials (Ip), electron affinity (Ea), optical band gap (Eg), peak potentials (Ep) and doping degree (y) of the polymers were calculated. Results were compared with the PCz homopolymer and the copolymer obtained from the mixture of MEKFR with carbazole P(Cz‐co‐MEKFR).

This study focuses on obtaining a conductive polymer by using a fluorescence comonomer which is an insulator. In order to remove pyridine from comonomer, successively washing with several portions of dilute aqueous H₂SO₄, water‐saturated aqueous sodium hydrogen carbonate, and hot water is necessary.

This work provides technical information for the synthesis of fluorescence comonomer and conducting an alternative polymer.

A new Cz‐CFR comonomer was synthesised. This comonomer has a higher T_m value than MEKFR alone and also has fluorescence property. The band gap of the copolymer is not remarkably lower than polycarbazole. The oxidation potential of P(Cz‐MEKFR) was found to be higher than the PCz homopolymer and the solubility of copolymer is 30 per cent higher than homopolymer.

The purpose of this paper is to report the synthesis of resins having conducting and fluorescence properties, with carbazole and oligocarbazole with a one step method of in situ modification of ketonic resin. Cyclohexanone‐formaldehyde (CFR), and acetophenone‐formaldehyde (AFR) resins were in situ modified with carbazole in the presence of sodium hydroxide.

Carbazole modified ketonic resins were synthesised by the condensation reaction of Cz, formaldehyde and ketone. Oligo carbazole was synthesised by redox reaction of carbazole and ceric ammonium nitrate (CAN). Then, for the in situ modification of oligo carbazole modified ketonic resin, reaction mixture of oligocarbazole carbazole was added to the cyclohexanone/formaldehyde solution.

The carbazole modified cyclohexanone‐formaldehyde and acetophenone formaldehyde resins have conductivity values of 10⁻⁵‐10⁻⁶ S/cm and may be considered as semi‐conductive ketonic resins. These new carbazole modified ketonic resins (CCzFR, ACzFR) have fluorescence properties.

This study focused on obtaining a conductive and fluorescence resin using a carbazole monomer which is an insulator.

This study provides technical information for the synthesis of fluorescence comonomer.

New CCzFR, ACzFR comonomers were synthesised. These comonomers have higher Tm values than CFR and AFR alone and also have fluorescence property.

Cyclohexanone‐formaldehyde resins (CF‐Rs) were in situ modified with aniline, 4‐aminodiphenylamine, and N‐N′‐diphenyl‐1,4‐phenylene diamine in presence of sodium hydroxide. The purpose of this paper is to report the synthesis of conducting resins with aniline, dimer and trimer aniline, with a one‐step method of in situ modification of ketonic resin. The roles of ketone, aniline concentration, the conductivity of the product are investigated.

Ketone, formalin (37 per cent aqueous solution), aniline or oligoaniline were mixed and 20 per cent aqueous NaOH solution was added to produce the resin.

The aniline‐modified (CF‐Rs) were found to have conductivity values of 10⁻³‐10⁻⁵ S/cm and may be considered as conductive ketonic resin.

The reaction mixture must be stirred continuously. Amount of aniline and oligoaniline is limited. Subsequently, 37 per cent formalin was added dropwise in total while refluxing. The amount of aniline is limited since the formed resin may become insoluble in common organic solvents.

This work provides the application of conducting resins. The modified resins containing aniline groups may also promote the adhesive strength of a coating and corrosion inhibition to metal surfaces.

Aniline formaldehyde, N‐N′‐diphenyl‐1,4‐phenylenediamine‐formaldehyde, aniline‐ and oligoaniline‐modified (CF‐Rs) have been synthesised in the presence of a base catalyst. These resins are conductive resins and the ketonic resins formed have physical properties of both aniline‐formaldehyde resins such as conductivity.

An intelligent gas sensor has been developed using thick‐film techniques to create a semiconducting oxide surface with carefully varied catalytic properties. An integral heater causes the surface to react with combustible gases and the resulting resistance map of the surface forms a signature that can be related to the functional groups present in the gas. For example, alcohols, ketones and alkanes have distinct, recognisable signatures on one sensor model.