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The improvement of the compatibility between two nonpolar rubber blends has a pivotal role to obtain superior blend properties. In this work, we utilized a facile and biofriendly modification approach of natural bentonite (BT) clay by two renewable resins, namely antibacterial gum rosin (GR) and soybean long oil alkyd resin (LAR). Which are considered to be toxicity-free reinforcing substance, thus preserving the bio-character of the substance. They used to increase the interlayer spacing distance between the BT galleries. This was proven by XRD and FT-IR. Natural rubber (NR)/styrene-butadiene rubber (SBR) blend was loaded with variable proportions of EBT-based GR and LAR bio-resins ranging from 3 to 15 wt.%. The ultrasonic and tensile properties were used to assess the compatibility between the rubber blends. The outcomes revealed that NR/SBR-3EBT-GR and NR/SBR-15EBT-LAR nanocomposites possessed higher tensile strength and rapture at break. Furthermore, the proposed mechanism of EBT by GR and LAR bio-resins with NR/SBR blend was studied. The both nanocomposites were then subjected to different measurements such as morphology by SEM and TEM, H-pull-out adhesion between rubber blends and polyester (PET) cords, and antibacterial activity. These new filled blend systems can be effective supporting a wide range of potential applications such as green tubeless tires technologies. [ABSTRACT FROM AUTHOR]

In this paper, self‐healing microcapsules were prepared by in situ polymerization using poly(vinyl alcohol) as the emulsifier, urea‐formaldehyde resin as the shell material, and alkyd resin as the core material. The average diameter of the obtained microcapsules was about 20 μm and the encapsulation rate of alkyd resin was 50.7 wt.%. The self‐healing coating was prepared by adding 5 wt.% of microcapsules to the pure polyurethane coating and then coated on AA2024‐T3 substrate. The self‐healing effect was evaluated by scanning electron microscopy. Electrochemical impedance spectroscopy tests and neutral salt spray tests confirmed that the self‐healing coating had good anticorrosion properties. [ABSTRACT FROM AUTHOR]

This article introduces a new method in which tung oil is employed as a bio‐friendly curative substance enclosed within melamine‐urea‐formaldehyde microcapsules. Due to the high reactivity of melamine, particle agglomeration can occur. To tackle this issue, this study focuses on optimizing the quantity of emulsifiers to achieve the best microcapsules with 15% melamine in the shell structure without particle agglomeration. The impact of melamine content and the quantity of emulsifier on the morphology of the synthesized microcapsules, the reaction yield, core content, and the hardness of the microcapsule shell were investigated. The presence of tung oil in melamine‐urea‐formaldehyde microcapsules was proven by Fourier transform infrared spectroscopy (FT‐IR). Field emission scanning electron microscopy (FESEM) revealed the spherical morphology of the capsules with a mean diameter of 2.29 μm. UV–vis analysis and nano‐indentation tests were used to evaluate the core content and the hardness of the result microcapsules, respectively. Finally, one sample, as the best microcapsule, was dispersed in an alkyd‐based resin in the amount of 1, 2.5, and 5 wt% and applied on a steel substrate for its ability to prevent corrosion. The study also highlights the adverse effect of excessive capsule usage in the resin, as demonstrated by reduced resin adhesion to the substrate, according to electrochemical impedance spectroscopy (EIS) and salt spray tests. The study found that the best long‐term anticorrosion properties are achieved by including 1 wt% of microcapsules in an alkyd resin. [ABSTRACT FROM AUTHOR]

This study aims to develop alkyd-aldehyde and alkyd-ketone blends by modification of waste poly(ethylene terephthalate) (PET) based alkyd resin with urea-aldehyde (UA) and cyclohexanone formaldehyde (CHF) resins for use in coating applications. PET flakes were depolymerized by simultaneous hydrolysis-glycolysis reaction, and depolymerization product (DP) was used completely instead of the diol in the alkyd synthesis. For comparison, reference alkyds without PET were also synthesized. The effect of modifier resin at different ratios and the presence of DP on the coating and thermal properties of blend films were investigated. Medium-hard/hard and gloss/high gloss films with excellent adhesion and impact resistance were obtained from both blends. These films also demonstrated superior chemical and environmental resistance. Blends with CHF resin had better alkali resistance than those with UA resin. In PET-based blends, thermal resistance significantly increased with the addition of the CHF resin to the alkyd resin. Notably, the use of DP did not show a negative effect on the properties of alkyd resin and blend films. On the contrary, much better results were obtained than the alkyd resin alone. Overall, the modification with UA and CHF modifiers and using DP improved the coating properties of the blends. These blends are expected to be considered a sustainable and environmentally friendly alternative for designing versatile coatings for various applications. [ABSTRACT FROM AUTHOR]

The aim of this paper was to investigate intumescent coatings based on polyfurfuryl alcohol (PFA) resin as a binder benefiting from high char yield and low smoke emission. To this end, the coatings composition in terms of PFA binder resin, long oil alkyd plasticizing resin, TiO2 pigment, and flame-retardant additives (FR) was changed as input parameters according to a mixture design-of-experiments. The corresponding changes in the backside temperature of mild steel substrate (Tb), residual char expansion ratio, limiting oxygen index, and char residue (wt% @1000 °C) were studied as the response variables describing fire performance characteristics of the coatings. The results showed that the backside temperature of the plate increased and the expansion ratio decreased with increasing in the alkyd resin concentration. Also, the flame-retardant efficiency of coatings strongly depends on the content of FR additives. When the content of PFA and alkyd resin was increased at a high level (35 and 4 wt%, respectively), the Tb of the coated plates reached 415 °C rapidly, due to the cracking of the coating and the lower concentration of FR additives. However, the formula with higher FR content, i.e., 68 wt%, showed the lowest Tb value ca. 128 °C. Flame-retardant characteristics directly depended on the expansion ratio of the coatings and the morphology of the char layer remaining on the substrate after the flame test; therefore, coatings with a higher expansion ratio showed lower backside temperature. The findings were supported by examining of the remaining char morphology after a flame test by optical microscopy and validated by comparing the predicted and actual responses for optimization. The value of absolute relative deviation was obtained in the range of 1.6–7.9, which indicates a good agreement between the proposed and experimental results. [ABSTRACT FROM AUTHOR]

The current work was developed focusing on the synthesis of new polymeric latexes through the in reactor oxidative polymerisation of chia oil alkyd resins using the miniemulsion process. These latexes have potential applications, primarily in coating applications. Initially, an oil length mixture was obtained from chia oil through saponification and acidification reactions. The resulting mixture was characterized by 1H-NMR and 13C-NMR, confirming the presence of unsaturation and the characteristic functional groups associated with this compound. Phthalic anhydride and glycerol (esterification reaction) were used in the synthesis of alkyd resin. Alkyd resins were obtained by varying the oil length content in its composition: 30% wt% oil length alkyd resin is called short alkyd resin, 43% wt% oil length is medium resin and 64% wt% is the long alkyd resin. The 1H NMR spectra of alkyd resins showed peaks indicative of the presence of groups coming from phthalic anhydride and glycerol, as well as unsaturations that varied in intensity according to the size of the resin (short, medium or long). The miniemulsions were obtained from alkyd resins demonstrating colloidal stability over 90 days and with stable miniemulsions the oxidative polymerisation of the alkyd resins was carried out in a high-pressure reactor with temperature and pressure control and in the presence of the radicalinitiator benzoyl peroxide (BPO) and oxygen. Based on 1H-NMR analysis, polymers are formed through the oxidative polymerisation of alkyd resins from chia oil using the miniemulsion process. These polymers can be used as a paint base with a low solvent fraction or no solvent, depending on the application, and without using heavy metals-based catalysts. [ABSTRACT FROM AUTHOR]

• A multi-analytical approach for the characterization of colored modern paints was developed. • The method allowed to indentify pigments, binding media and additives for the organic and inorganic characterization of reference samples. • Chronological data about modern paint components was obtained by correlating the chemical information with data compiled from books, articles and patents. • Analytical results and chronological information were compiled into integrated charts to estimate the manufacturing period. • The developed methodology was successfully applied to corroborate the estimated date of an artwork presumably produced in 1946. Throughout the twentieth century, the paint industry developed a multitude of new binding media, pigments and additives that improved the appearance, ease of application, and performance of modern industrial paints. Depending on when and where they were first manufactured, and when they were introduced into paint formulations, some of these new paint components could conceivably be chronological markers useful in assigning attribution to specific artists or in the study of forgeries. The aim of this study was to develop a systematic methodology for characterizing organic and inorganic materials in modern paints, and search for potential chronological markers. Colored reference paints manufactured by local companies in Argentina from the 1940s and 1950s were studied with a multi-analytical approach that included Fourier-transform infrared spectroscopy, gas chromatography coupled with mass spectrometry, Raman spectroscopy, X-ray diffraction, X-ray fluorescence and scanning electron microscopy with energy dispersive X-ray analysis. A wide range of compounds was identified due to the complementarity use of the analytical techniques. Historical references, patents, books, and scientific publications about the materials used in that time period provided invaluable information in establishing tentative timelines for modern paint components. This investigation was part of a broader interdisciplinary investigation of Concrete Art, an international art movement of the beginning of the twentieth century, which took place in Argentina and other nearby countries during the 1940s and 1950s. To prove the concept, a micro-sample from "Obra N° 171" by Raúl Lozza was analyzed. Organic and inorganic fractions were studied and the information collected was correlated with developed timelines to support the authentication process. Ultimately, the information from this study may also have a direct impact on the key areas of material characterization, aging behavior, and conservation of works of art made from these products. [Display omitted] [ABSTRACT FROM AUTHOR]

Due to the significant importance of waterborne polymers in terms of sustainability, researchers have undertaken the process of transferring alkyd resins into waterborne latex. In this study, two distinct types of alkyd resins were meticulously prepared through the esterification of sustainable sources, namely hemp seed oil (HSO) and pine fatty acid (TOFA), with polyols and dibasic acids. The goal of this research was to synthesize hydrophobic waterborne hybrid polymer emulsions, combining alkyd and styrene acrylic components. This was achieved through a semibatch mini-emulsion polymerization process involving styrene, butyl acrylate, and acrylic acid. The alkyd resins, derived from sustainable sources, were integrated into the polymerization process along with hydrophobic monomers that contained either fluorine or silane groups. Based on the alkyd content, polymer emulsions were examined in three classes: pure polymer emulsions without alkyd (0% alkyd), 10% HSO-based alkyd-containing polymer emulsions (10% HSO-based), and 10% TOFA-based alkyd-polymer emulsions (10% TOFA). Polymer emulsions in each class were first modified with 3% and 6% triethoxyvinyl silane (VTES) and 2,2,2-trifluoroethyl methacrylate (TFEMA) to obtain a total of 12 different modified latexes. The structure of the synthesized latex was characterized by FTIR and 1H-NMR, while the morphology of the latex was examined by AFM, STEM, EDAX, particle size, and zeta potential measurements. The thermal and mechanical properties of the materials were assessed using DSC, TGA, and tensile testings. Lastly, the water contact angle was used to gauge the hydrophobicity of the latexes. The findings revealed that TFEMA and VTES hydrophobic monomers significantly influenced the mechanical, thermal, and hydrophobic properties of hybrid (alkyd/styrene acrylic) polymer emulsions and films. [ABSTRACT FROM AUTHOR]

The accelerated degradation of alkyd resins via γ-irradiation is investigated using non-isothermal chemiluminescence. The stability qualification is possible through the comparison of emission intensities on a temperature range starting from 100 °C up to 250 °C under accelerated degradation caused by radiolysis scission. The measurements achieved in the samples of cured state resin modified by various inorganic oxides reveal the influence of metallic traces on the aging amplitude, when the thermal resistance increases as the irradiation dose is augmented. Even though the unirradiated samples present a prominent chemiluminescence intensity peak at 80 °C, the γ-processed specimens show less intense spectra under the pristine materials and the oxidation starts smoothly after 75 °C. The values of activation energies required for oxidative degradation of the sample subjected to 100 kGy are significantly higher in the composite states than in the neat resin. The degradation mechanism of polymerized resins is discussed taking into account the effects of fillers on the stability of studied epoxy resin at various temperatures when the degradation and crosslinking are in competition for the decay of free radical. [ABSTRACT FROM AUTHOR]

The advent of organic polyester alkyd resin has revolutionized the coating industry due to its good adherence to any substrate, high gloss, and greater drying speed. This work deals with the characterization of nano calcium fluoride (CaF2 Nps) incorporated polyester alkyd coating for efficient multifunctional coating applications. The CaF2 Nps are prepared by employing a facile co‐precipitation process. The prepared particles are characterized using X‐ray diffraction analysis (XRD) and scanning electron microscopy (SEM) to analyze their size and morphology. By employing the ball milling technique, the CaF2 Nps along with other additives are mixed with alkyd resin to form a coating. The spreading ability, volatile and non‐volatile content, surface roughness, and coating thickness are evaluated. The minimal inhibitory concentration (MIC) is estimated by the turbidimetric assay method against gram‐negative and gram‐positive bacteria strains. Since these pigments hold very good antibacterial properties, the CaF2 are impregnated in alkyd resin coating, in which CaF2 nanoparticles are used as pigments. To reduce the nosocomial infection spreading in the hospital environment the formulated paint is analyzed for its antibacterial and anticorrosive studies. The current study confirmed CaF2 impregnated organic alkyd resin coating possesses promising comparable properties which would be a good choice for coatings, addressing multifunctional properties. [ABSTRACT FROM AUTHOR]

In this work a hyperbranched alkyd resin (HBAR) was synthesized from a hyperbranched polyester polyol of fourth-generation (HBP4) and tall oil fatty acids. Furthermore, the HBAR was modified with several proportions (10, 20, 30, and 40 wt%) of maleic anhydride (MA) to obtain maleinized HBAR (HBARMAs). The structural, thermal, rheological, and film properties of the HBAR and HBARMAs were evaluated for the purpose of estimating the effect of MA content on the properties of the HBARMAs. HBARMAs exhibited hydroxyl values inferior to that of the HBAR and it decreased with the MA content. Infrared and proton nuclear magnetic resonance (1H NMR) analyses provided evidence of the formation of the HBAR and HBARMA. The number average molar mass ( M n ) of the HBP4 was lower than that of the HBAR, but those of the HBARMAs were higher. Using dynamic light scattering analysis, it was observed that HBAR exhibited smaller hydrodynamic dimensions than HBARMAs. The glass transition temperature (Tg), onset decomposition temperature (Tonset), and viscosity (η) values of the HBARMAs increased with the MA content and it was higher than those of the HBAR. However, the drying time exhibited the opposite behavior. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to prepare new modified alkyd resins and use it as an antimicrobial binder for surface coating applications. Design/methodology/approach: Various modified alkyd resins were prepared by partial replacement of 3,6-dichloro benzo[b]thiophene-2-carbonyl bis-(2-hydroxy ethyl)-amide as a source of polyol with glycerol and confirmed by acid value, FT-IR, 1H-NMR. The modified alkyd resins were covering a wide range of oil lengths and hydroxyl content (0%, 10%, 20% and 30% excess-OH). The antimicrobial activity of the prepared alkyds was also investigated. The coatings of 60 ± 5 µm thickness were applied to the surface of glass panels and mild steel strips by means of a brush. Physico-mechanical tests, chemical resistance and antimicrobial activities were investigated. Findings: The obtained results illustrate that the introduction of benzo[b]thiophene derivative as a modifier polyol within the resin structure improved the film performance and enhanced the physico-mechanical characteristics, chemical resistance and the antimicrobial activities. Practical implications: The modified alkyd resins can be employed as antimicrobial binders in paint compositions for a variety of surfaces, particularly those that are susceptible to a high number of bacteria. Originality/value: Modified alkyd resins based on antimicrobial heterocyclic compounds have the potential to be promising in the manufacturing of antimicrobial coatings and development of paints, allowing them to function to prevent the spread of microbial infection, which is exactly what the world requires at this time. Also, they can be applied in different substrates for industrial applications. [ABSTRACT FROM AUTHOR]

In this study, we investigated the effect of organosilane monomer on the adhesion strength and corrosion protection of the water-reducible alkyd coatings. For this purpose, firstly, alkyd resin was synthesized and modified with acrylic monomers by changing organosilane monomer content in the range of 4–16 wt% in all acrylic monomer compositions. Then, the carboxyl groups on the hybrid resins were neutralized with a base and the coating recipes were formulated using these water-reducible resins. The chemical structure and composition of the synthesized polymers were confirmed using 1H-NMR and FTIR spectroscopies. Mechanical properties of coatings applied on the cold-rolled steel surfaces were investigated via crosshatch adhesion, pendulum hardness, gloss, impact, and conical mandrel bend tester. According to the results, it can be said that water-reducible acrylic-modified alkyd coatings offer a good balance of hardness and flexibility. Then, the line was scratched parallel to the coating system and the surface coating properties of the coated panels, such as the adhesion strength after being exposed to humidity and corrosion resistance, were comparatively investigated. The best results for corrosion resistance and adhesion strength were obtained with the coating which was formulated with the resin having organosilane monomer of 8 wt% in all acrylic monomer mixtures. As the organosilane monomer amount increased to 16 wt%, the coatings' corrosion resistance and adhesion strength decreased. As a result, it was observed that organosilane modification is significantly effective in improving the adhesion strength and corrosion resistance of water-reducible alkyd coatings. However, increasing the amount of silane monomer may reverse the positive results obtained. This study also reveals significant results about the correlation between the adhesion strength and corrosion resistance of coatings by presenting visual results. [ABSTRACT FROM AUTHOR]

The polymerization and properties of environmentally friendly resin binders applicable in the surface-coating industry were studied. Rubber seed oil (RSO) and RSO blended with 10% and 20% soybean oil (SBO)-based alkyd resins were synthesized by alcoholysis-polyesterification of the oil with glycerol and phthalic anhydride. Physicochemical properties (such as colour, specific gravity, acid value, saponification value, iodine value, and drying schedule) of the alkyd resins were determined to establish the possible industrial potential of the resins. The saponification value and iodine value ranged from 250.19 mgKOH/g to 279.55 mgKOH/g and 29.58 gI2/100g to 33.77 gI2/100g respectively. The drying schedule and chemical resistance of the blended alkyd resins to water, salts, acids, and alkalis were also studied. The blended resins were found to be resistant to water, salt, and acid media, except for alkali media. The colour properties were enhanced as the percentage of the blend increased. FT-IR spectroscopic study of the oil and alkyd resin samples further corroborates our findings. Therefore, the potential of rubber seed oil blended with soybean oil to produce light-coloured alkyd resins could be exploited as raw materials for the Nigerian surface coating industry. [ABSTRACT FROM AUTHOR]

Since alkyd resins include hazardous solvents, converting alkyds into waterborne hybrid polymers is an essential research topic. Here, alkyd/styrene acrylic waterborne hybrid polymers were synthesized in the presence of monomers, water, emulsifiers, and an initiator by using synthesized alkyd resins at 0%, 5%, 10%, and 15% ratios based on the total monomer ratio. A mini-emulsion technique and a semi-batch polymerization method were used to synthesize the latexes. Two different biosources, tall oil fatty acids (TOFA) and hemp seed oils (HSO), were used to synthesize the alkyd resins. Synthesized waterborne hybrid latexes and their films were analyzed by using FTIR, NMR, particle size, MFFT, TGA, DSC, CA, AFM, and mechanical tests. It was determined that the type and concentration of the alkyds affected the viscosity, particle size, Tg and MFFT values, and appearance. It was also identified that alkyd incorporation took place with grafting and that the alkyd concentration was particularly effective in increasing the particle size. In addition, experiments were carried out on waterborne paint systems for exterior paint by using synthesized hybrid polymer emulsions. It was observed that the alkyd content was not effective in changing the paint color in hybrid latexes. As a result, it is suggested that hybrid waterborne latexes could be used for exterior paints. [ABSTRACT FROM AUTHOR]

Cardanol, a waste from the food industry and widely produced (1 Mt/y), has been used as a chain stopper during the polycondensation of short oil alkyd resins in order to replace benzoic acid. Then, phosphorylated cardanol has been added in order to both reduce solvent content and bring flame-retardant (FR) properties to the alkyd resins. The renewable carbon content of the formulations has been increased up to 23%. The impact of the introduction of phosphorylated cardanol molecules on the drying time and flexibility has been studied as well as the thermal and flame-retardant properties by differential scanning calorimeter, thermogravimetric analysis and pyrolysis-combustion flow calorimeter. The most effective flame-retardant coating that was associated with excellent FR properties and excellent coating properties has been obtained with phosphate-cardanol added at 2%wt of P. Indeed, the film properties were closed to the classical alkyd resin, the solvent content was reduced by 50% and the pHRR decreased by 42% compared to the reference alkyd resin.

This work addresses a comparative study focused on the synthesis of alkyd resins from different renewable resources such as chia, castor and palm vegetable oils through the alcoholysis–polycondensation process. The formed alkyd resins are analyzed by Fourier transform infrared (FTIR), 1H NMR, and 13C NMR. Besides, intrinsic viscosity and gel permeation chromatography (GPC) assays are conducted to evaluate the differences between the obtained resins focusing on their molecular weight and physicochemical properties. FTIR shows a satisfactory conversion from vegetable oils to alkyd resins. Both 1H NMR and 13C NMR indicate that alkyd resins are successfully synthesized. The values for molecular‐weight dispersity (ÐM) obtained for the resins are 2.3, 1.3, and 1.7 from chia, palm, and crude castor, along with the weight‐average molecular weight (Mw) of 4516, 1025, and 2451 g mol−1, respectively. The chia alkyd resin shows a 571.92 cP and is the highest viscosity obtained. It is also observed that an increase in phthalic anhydride can increase the molecular weight of the alkyd resin. This comparative study indicates that chia oil alkyd resin has enormous potential to be employed as a surface coating agent. [ABSTRACT FROM AUTHOR]

The first aim of this study was to synthesize hyperbranched alkyd resins from tall oil fatty acids and a hyperbranched polyester polyol via an esterification reaction. The second aim was to evaluate the effect of the fatty acid proportion on the properties of the resins. The modification percentage of the hyperbranched polyester polyol was between 47.68 and 66.02%. Infrared analysis shows that the alkyd resins decreased the intensity of the OH group's vibration. This decrease depends on the amount of TOFA used. Thermogravimetric and differential scanning calorimetry analyses showed that the modification of the hyperbranched polyester improved the thermal stability and the mobility of the macromolecules of the alkyd resins respectively. The viscosity of the alkyd resins was less than 10 Pa.s. They exhibited Newtonian behavior and had the highest gloss values at 60° (between 90.1 and 91.6). [ABSTRACT FROM AUTHOR]

Plastic pollution is an international problem to the limit that World Environment Day, made its theme on the 5th of June 2023: Beat plastic pollution. The Nile is suspected to be a source of such pollution that pour into the Mediterranean Sea. In this respect, the present work was carried out on 127 O. niloticus, as a surface feeder, and 32 C. gariepinus from Bahr Shebeen Nilotic Canal. The occurrence of microplastics varied with species and seasons. This did not exceed 10 particles per fish. The percentage occurrence was 33.9 for O. niloticus and 59.4 for C. gariepinus. Food and feeding and seasonal variations were examined and discussed, in the light of the shape and color of MPs with the length of fish. Colors of pink, red, and blue showed the highest occurrence in either species, while Fragments and fibers were found to be the highest. Identified polymers were shown to be polyamide, alkyd resins, polyethylene, polyethylene terephthalates and rayon. The highly occurring of those are polyamides and rayon in both species. [ABSTRACT FROM AUTHOR]

In our paper, we have synthesized modified PEA and alkyd resin by replacing the new source of polyol (SDEA) which was confirmed by different analyses such as IR, and 1HNMR spectra. A series of conformal, novel, low-cost, and eco-friendly hyperbranched modified alkyd and PEA resins were fabricated with bio ZnO, CuO/ZnO) NPs through an ex-situ method for mechanical and anticorrosive coatings. The synthesized biometal oxides NPs and its composite modified alkyd and PEA were confirmed by FTIR, SEM with EDEX, TEM, and TGA, and can be stably dispersed into modified alkyd and PEA resins at a low weight fraction of 1%. The nanocomposite coating was also subjected to various tests to determine their surface adhesion, which ranged from (4B-5B), physico-mechanical characteristics such as scratch hardness, which improved from < 1.5 to > 2 kg, gloss (100–135) Specific gravity (0.92–0.96) and also chemical resistance test which passed for water, acid, and solvent except alkali, was poor because of the hydrolyzable ester group in the alkyd and PEA resins. The anti-corrosive features of the nanocomposites were investigated through salt spray tests in 5 wt % NaCl. The results indicate that well-dispersed bio ZnO and CuO/ZnO) NPs (1.0%) in the interior of the hyperbranched alkyd and PEA matrix improve the durability and anticorrosive attributes of the composites, such as degree of rusting, which ranged from 5 to 9, blistering size ranged from 6 to 9, and finally, scribe failure, which ranged from 6 to 9 mm. Thus, they exhibit potential applications in eco- friendly surface coatings. The anticorrosion mechanisms of the nanocomposite alkyd and PEA coating were attributed to the synergistic effect of bio ZnO and (CuO/ZnO) NPs and the prepared modified resins are highly rich in nitrogen elements, which might be regarded as a physical barrier layer for steel substrates. [ABSTRACT FROM AUTHOR]

Alkyd resins are oil-based polymers that have been widely used for generations in the surface coating industry and beyond. Characterization of these resins is of high importance to understand the influence of its components on its behavior, compatibility with other resins, and final quality to ensure high durability. Here, NMR spectroscopy and GPC were used for characterizing differences in the chemical structure, molecular distribution, and dispersity between oil-based and fatty acid-based alkyd polymers made from sacha inchi and linseed oils. Sancha inchi (Plukentia volubilis L.) is a fruit-bearing plant native to South America and the Caribbean, and has a rich unsaturated fatty acid content. The effect of vegetable oil and polyol selection on the synthesis of alkyd resins for coating applications was analyzed. The influence of two different synthesis methods, monoglyceride and fatty acid processes, was also compared. Important structural differences were observed using NMR: one-dimensional spectra revealed the degree of unsaturated fatty acid chains along the polyester backbone, whereas, 2D NMR experiments facilitated chemical shift assignments of all signals. GPC analysis suggested that alkyd resins with homogeneous and high molecular weights can be obtained with the fatty acid process, and that resins containing pentaerythritol may have uniform chain lengths. [ABSTRACT FROM AUTHOR]

Today's requirements in the art field have challenged researchers to create artistic paintings with attractive appearance and long‐term color stability. Alkyd‐based art mediums have become an important group in the art field, because of their similar characteristics to traditional oils and exceptional drying properties. In this work, high solid alkyd‐based art mediums have been synthesized by the monoglyceride and acidolysis processes. Multifunctional polyols and high unsaturated fatty acid sources were compared and used for alkyd synthesis. The use of a non‐traditional oil of Peruvian origin is proposed. Resins have been characterized according to their physicochemical (acid number, viscosity, color and density) and drying properties. Drying tendencies were verified with the use of quartz crystal microbalance. Also, the behavior of the art mediums mixed with commercial oil paintings and a dry pigment, have also been evaluated. Results indicate that resins containing the polyol with the highest functionality are more viscous and have fewer tendencies to yellowing, while non‐traditional Peruvian oil is the best option for creating light‐colored art mediums. Alkyd mediums prepared by the monoglyceride method gave to oil paintings better characteristics and drying behavior on canvas. [ABSTRACT FROM AUTHOR]

Bangladesh is a deltaic country in Asia, and its riverine systems ultimately drain into the Bay of Bengal. Plastic is a severe environmental issue for coastal-marine ecosystems due to the indiscriminate usage and discarding of plastic items in the upstream river that eventually find their route into the Bay of Bengal. Microplastics (MPs) are widespread pollutants in almost all environmental compartments, including aquatic environments. This study aimed to quantify and understand the distribution of microplastics in surface water and sediments of the river Karnaphuli, a tidal confluence river adjacent to the Chattogram seaport city of Bangladesh, a highly inhabited and industrial area on the southeast coast of the Bay of Bengal. A manta trawl net (300-µm mesh size) was used to collect surface water samples, while an Ekman dredge was used to collect sediment samples. The concentrations of microplastics in the surface water of the river Karnaphuli during late monsoon, winter, and early summer were recorded to be 120,111.11, 152,222.22, and 164,444.44 items/km2, respectively, while in sediments, those were recorded to be 103.83, 137.50, and 103.67 items/kg, respectively. A higher abundance of microplastics was observed in downstream surface water (228,888.88 items/km2) and sediments (164.17 items/kg). Smaller sizes (0.3 to 0.5 mm) of microplastics were predominant, fibers or threads were the frequent types, and black was the most common color in the river Karnaphuli. The Fourier transform infrared analysis revealed that polyethylene terephthalate (surface water: 22%, sediments: 19%), polyamide (surface water: 15%, sediments: 13%), polyethylene (surface water: 12%, sediments: 18%), polystyrene (surface water: 13%, sediments: 11%), and alkyd resin (surface water: 13%, sediments: 10%) were the most prevalent polymers in the river Karnaphuli. Moreover, there was a moderate positive correlation between MPs abundance in surface water and sediments. Therefore, improved long-term research (in different seasons with horizontal and vertical monitoring) is necessary in order to accurately determine the flux of microplastics from the river Karnaphuli to the Bay of Bengal. [ABSTRACT FROM AUTHOR]

Cardanol, a waste from the food industry and widely produced (1 Mt/y), has been used as a chain stopper during the polycondensation of short oil alkyd resins in order to replace benzoic acid. Then, phosphorylated cardanol has been added in order to both reduce solvent content and bring flame-retardant (FR) properties to the alkyd resins. The renewable carbon content of the formulations has been increased up to 23%. The impact of the introduction of phosphorylated cardanol molecules on the drying time and flexibility has been studied as well as the thermal and flame-retardant properties by differential scanning calorimeter, thermogravimetric analysis and pyrolysis-combustion flow calorimeter. The most effective flame-retardant coating that was associated with excellent FR properties and excellent coating properties has been obtained with phosphate-cardanol added at 2%wt of P. Indeed, the film properties were closed to the classical alkyd resin, the solvent content was reduced by 50% and the pHRR decreased by 42% compared to the reference alkyd resin. [ABSTRACT FROM AUTHOR]

Urethane-modified alkyd resins were synthesized using the depolymerization intermediates obtained from simultaneous hydrolysis–glycolysis reactions of post-consumer poly(ethylene terephthalate) (PET) bottles with dipropylene glycol (DPG) and water. For this aim, first, the synthesis of a four-component reference alkyd resin having an oil content of 50% was synthesized by using tall oil fatty acid (TOFA), trimethylolpropane (TMP), phthalic anhydride (PA), and dipropylene glycol (DPG). The PET-based alkyd resins were also synthesized using different amounts and types of purified and fractionated depolymerization intermediates (water-insoluble fraction, WIF, and water-soluble and crystallizable fraction, WSCF) under the same reaction conditions. For the synthesis of PET-based alkyd resins, the depolymerization intermediates were used partially or completely instead of dibasic acid and/or diol components in alkyd resin formulations. In order to determine the optimum modification ratio for urethane-modified alkyd resin synthesis, the reference alkyd resin was reacted with toluene diisocyanate (TDI) at different molar ratios (NCO/OH: 1/1, 1/2, and 1/3), and the optimum NCO/OH ratio was determined as 1/1, according to the surface coating properties. And, then, all PET-based urethane-modified alkyd resins were prepared by the modification reactions of the PET-based alkyd resins with TDI at an optimum ratio. At the end of the study, it was observed that the use of waste PET intermediates (WIF or WSCF) did not cause any negative effects on physical/chemical surface coating and thermal properties; on the contrary, some properties were obtained as superior than that of the reference resin. In conclusion, it seems possible to use PET-based urethane-modified alkyd resin could be used as a cheap, environmentally friendly, and relatively economic binder component in synthetic paint formulations. In the synthesis of urethane-modified alkyd resin, using a certain amount of waste PET intermediate instead of dibasic acid and/or diol component will reduce raw material costs and also benefit the environment by re-evaluation of recycled PET. Thus, it could be both possible to recycle of post-consumer PET bottles, which are a valuable waste, and to provide cheap raw materials without compromising its features for paint formulations. These results are remarkable in terms of sustainability and waste management besides are also important for the economy and paint industry. [ABSTRACT FROM AUTHOR]

Four types of UV-(meth)acrylate curable alkyds were synthesized and formulated with two tri(meth)acrylate reactive diluents. Thermal, mechanical, and coating properties, including gloss, adhesion, hardness, impact resistance, and chemical resistance, were evaluated. In general, methacrylate-based UV-curable alkyd has higher modulus and toughness, whereas acrylate-based UV-curable alkyd has better flexibility and adhesion. In all four UV-curable alkyd resin systems, increasing reactive diluent content will enhance properties like tensile strength and modulus, hardness, and chemical resistance. However, there is a decrease in properties such as elongation at break, adhesion, and impact resistance. Among four UV-curable alkyd resin, acrylated medium linseed oil alkyd exhibited the best overall performance than other systems in terms of hardness, flexibility, and adhesion. Particularly, acrylated medium linseed oil alkyd formulations with 20–30 wt% of glycerol triacrylate as reactive diluent showed the best coating performance. It is possible to produce coating films with a good balance of crosslink density, flexibility, and adhesion using such UV-curable alkyd systems. Further, it has a huge potential in alkyds as an alternative for cobalt-based drier system. [ABSTRACT FROM AUTHOR]

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Microplastics (MPs) are ubiquitous in the environment, in the human food chain, and have been recently detected in blood and lung tissues. To undertake a pilot analysis of MP contamination in human vein tissue samples with respect to their presence (if any), levels, and characteristics of any particles identified. This study analysed digested human saphenous vein tissue samples (n = 5) using μFTIR spectroscopy (size limitation of 5 μm) to detect and characterise any MPs present. In total, 20 MP particles consisting of five MP polymer types were identified within 4 of the 5 vein tissue samples with an unadjusted average of 29.28 ± 34.88 MP/g of tissue (expressed as 14.99 ± 17.18 MP/g after background subtraction adjustments). Of the MPs detected in vein samples, five polymer types were identified, of irregular shape (90%), with alkyd resin (45%), poly (vinyl propionate/acetate, PVAc (20%) and nylon-ethylene-vinyl acetate, nylon-EVA, tie layer (20%) the most abundant. While the MP levels within tissue samples were not significantly different than those identified within procedural blanks (which represent airborne contamination at time of sampling), they were comprised of different plastic polymer types. The blanks comprised n = 13 MP particles of four MP polymer types with the most abundant being polytetrafluoroethylene (PTFE), then polypropylene (PP), polyethylene terephthalate (PET) and polyfumaronitrile:styrene (FNS), with a mean ± SD of 10.4 ± 9.21, p = 0.293. This study reports the highest level of contamination control and reports unadjusted values alongside different contamination adjustment techniques. This is the first evidence of MP contamination of human vascular tissues. These results support the phenomenon of transport of MPs within human tissues, specifically blood vessels, and this characterisation of types and levels can now inform realistic conditions for laboratory exposure experiments, with the aim of determining vascular health impacts. [ABSTRACT FROM AUTHOR]

Recently, due to the depletion of natural resources and raising environmental and economic concerns regarding petroleum derivatives, the creation of novel ecologically friendly and sustainable materials made from bio-based and renewable resources is gaining popularity. Alkyd resins are synthetic resins in which both renewable (fatty acids, glycerol, oil, etc.) and nonrenewable (maleic anhydride, pentaerythritol, phthalic anhydride, etc.) raw materials are used in their production. Due to their superior performance (good aging, greater weather resistance and high heat resistance, outstanding gloss, etc.) over other resins, easy application, low cost, and varied use, in the coating and paint industries, they are commonly used. This review covers the studies on bio-based monomers used instead of nonrenewable ones in the production of alkyds. The effects of substituted bio-based monomers on the final properties (adhesiveness, drying times, hardness, tackiness, etc.) of produced alkyds and coatings are also discussed in detail. [ABSTRACT FROM AUTHOR]

The paper deals with the influence of ageing in the dark and in the light on the colour of a transparent surface finish. In the experiments, Paper birch (Betula papyrifera Marsh) and Norway maple wood (Acer pseudoplatanus L.) were hydrothermally treated at 135 °C under saturated water vapour for 6 hours. The colour parameters were measured after native wood and thermally treated wood were surface finished. Three different types of surface finishes (acrylic-polyurethane, polyacrylic and aldehyde resin, and alkyd resin) were applied on the wood surfaces. The colour parameters of the tested surfaces (system CIE L*a*b*, chroma C*, hue angle h°) were measured immediately after surface finishing and ageing. The tested samples were aged either in the dark or in the sunlight behind windows glass, in the interior, for 60 days. The results showed that the colour of the wood and the colour of surface finishes changed after ageing in the dark and the light. The changes were different. The surfaces mostly lighten up in the dark and darken in the light. [ABSTRACT FROM AUTHOR]

The UV curing method is free from volatile organic compounds (VOC) and exhibits high curing efficiency. However, pore flaws and inadequate mechanical qualities after cure greatly hinder their utilization in metal anti-corrosion. Herein, layered double hydroxides (LDH) supported by molybdic acid and cerium ions were synthesized in situ on the sericite (SC) surface, enhancing the shielding, corrosion inhibition, resin compatibility, and cross-linking density of the coating. Compared with carbon steel immersed in a 3.5 wt% NaCl solution, the incorporation of SC/KH560@LDH reduced the corrosion current density (I corr) from 2.001 × 10−5 A/cm2 to 7.883 × 10−6 A/cm2. Moreover, the low-frequency impedance of the UV-SC/KH560@LDH coating remained high at 1.939 × 1010 Ω·cm2 after 70 days of immersion in a 3.5 wt% NaCl solution. The excellent corrosion resistance of UV-SC/KH560@LDH can be attributed to the barrier properties of the filler, the chloride ion trapping, and the passivation effect. Furthermore, the UV-curable alkyd resin used in this work formed a chemical bond with the metal substrate, enhancing the mechanical properties of the coating. The adhesion strength of the UV-SC/KH560@LDH was measured at 11.50 MPa. The thickness loss (21.3 μm) of the UV-SC/KH560@LDH were minimal after 5000 cycles of wear. A new research concept for preparing the UV-SC/KH560@LDH with superior anti-corrosion and mechanical properties for carbon steel plate surfaces has been proposed to meet the demands of practical applications. • LDH supported by molybdic acid and cerium ions were synthesized in situ on the SC surface. • Introducing UV alkyd resins into composite coatings to improve the overall performance of the coatings. • The UV-SC/KH560@LDH composite coatings enhance mechanical properties. • The low-frequency impedance of UV-SC/KH560@LDH coatings is approximately 343 times that of conventional UV-C-Resin coatings. [ABSTRACT FROM AUTHOR]

• IR reflective ZnO: Dy3+ pigment. • Synthesis techniques. • DRS spectral analysis. • Performance of the reflective paint. In this paper, we have discussed the heat reflective properties of ZnO: Dy3+ pigment synthesized by the combustion method and co-precipitation method. The phase purity and crystalline nature of the prepared pigment have been studied using XRD and SEM. The IR-reflective properties of the pigment DRS have been measured. A paint formulation of the ZnO: Dy3+ pigment was prepared in alkyd resin. The performance of the heat-reflective paint has been investigated by coating the glass surface. From the present investigation, it is seen that the prepared ZnO: Dy3+ pigment is well suited to increase the IR reflectance to cool the surface. [ABSTRACT FROM AUTHOR]

A series of biobased alkyd resins having hydroxyl functionalities was synthesized using Madhuca indica (mahua) seed oil as a renewable source on reaction with various diacids and anhydrides. Functional group transformation and alkyd formation were confirmed by ATR-FT-IR and proton NMR spectroscopies as well as by end group analysis. Polyols containing hydroxyl functionalities were utilized in combination with polymeric methylene diphenyl diisocyanate (PMDI) to produce polyurethane (PU) in the form of coatings, which were examined for their gloss, impact, flexibility, cross-cut adhesion, etc. Anticorrosion property of coatings was investigated by immersion method and by electrochemical method in an aqueous salt solution. Additionally, coatings were subjected to their thermal behavior study using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). While crystalline and amorphous behaviors of PUs were studied by X-ray diffraction (XRD). The mahua oil-based PUs revealed excellent coating properties, thermal stability, and anticorrosion performance. Thus, untapped mahua oil can act as a good source of replacement for petroleum in the preparation PU coatings. [Display omitted] • Mahua oil from barren land is utilized to synthesize alkyd polyols. • Alkyd polyols were used to develop renewable source based of PU coatings. • MO alkyd based PU coatings are with good coating properties. • PU coatings showed better anticorrosion performance as tested by immersion and electrochemical methods than uncoated panel. [ABSTRACT FROM AUTHOR]

Cover:The morphology (SEM image) of the urea‐formaldehyde‐alkyd resin microcapsules. The microcapsules were regularly globular in shape.More detailed information can be found in: Bin Xie, Hongwei Shi, Yingwei Song, En‐Hou Han, Self‐healing polyurethane anticorrosive coatings based on alkyd resin microcapsules, Materials and Corrosion 2024, 75, 1090..By Bin Xie; Hongwei Shi; Yingwei Song and En‐Hou HanReported by Author; Author; Author; Author [Extracted from the article]

Waterborne acrylic-alkyd resins with various acrylic resin contents were synthesized by free-radical polymerization on the alkyd resin side chains to produce copolymers with different molecular structures on the side chains to improve the coating corrosion protection properties. By copolymerizing the double bonds introduced on the alkyd resin with acrylic monomers and designing the side-chain structure of the alkyd resin, a denser crosslinking structure of the coatings can be achieved. This improves the thermal stability and corrosion resistance of the coatings. The denser crosslinked network is achieved by the flexibility of the highly branched acrylic resin and copolymer chains grafted on the side chains, making it more difficult for corrosive media to pass through the contact between the coating and the tinplate substrate. Gel permeation chromatography with thermogravimetric and electrochemical analyses showed that the highly branched side-chain structure enhanced the thermal stability and corrosion resistance of the coated samples compared to the small-molecule side-chain structure of the copolymers. This work illustrates that coating corrosion protection can be improved by optimizing the side-chain structure. • Waterborne acrylic-alkyd resins with different side-chain molecular structures were synthesized by free-radical polymerization to enhance corrosion resistance. • Acrylic acid was successfully grafted onto the side chain of alkyd resin by esterification reaction. • The improvement of the molecular structure of the side chains enhanced the water resistance, thermal stability and corrosion resistance of the resins. • A method to improve the anti-corrosion properties of coatings by optimizing the side-chain structure is described. [ABSTRACT FROM AUTHOR]

In the current review article, an effort has been made to emphasize the inner workings of alkyd resins, the earliest polymeric resin created from vegetable oils, in light of technological advancements that have occasionally been made to increase their practical utility. The thorough synthesis and use of several kinds of water-born alkyds were explained in order to lessen the use of organic solvents. To create one set of styrenated alkyds, the Styrene monomer was used to post-polymerize the alkyd at 5:5 ratio at 80 °C for 6 hours. 1 Standard techniques were used to define and assess the styrenated alkyds' physical and chemical characteristics, drying time, and chemical resistance. Each resin displayed favorable characteristics. Even without a dryer, the styrenated alkyds provided a quicker drying time2. The styrenated alkyds were resistant to alkali, in contrast to the unstyrenated alkyd, which is just resistant to conditions that are acidic, wet, or briny. The AAST's coatings The FTIR, HNMR, DSC, and TGA methods were used to confirm the structures of the changed resins that were obtained. The findings of the physico-mechanical tests demonstrated that the styrenated alkyds that were produced are suitable for a range of coating applications. [ABSTRACT FROM AUTHOR]

Although microplastic (size ≤5 mm) pollution in marine ecosystems has received global attention, the presence of microplastics and microfibers in indoor environments is also a major concern. Compared to the available field survey data on microplastics in the ocean, such information remains limited for indoor environments. Microplastics in indoor environments may act as adsorbents for chemical compounds, which may result in multiple adverse health effects on residents. Establishment of reproducible sampling and analysis methods aiding comprehensive field measurements of indoor microplastics in Japan is required. This study conducted the first field survey of indoor microplastics in settled dust in 10 residential houses in the Kanto area of Japan and explored their composition and morphology. Micro‐Fourier transform infrared (μ‐FT‐IR) spectrophotometry and laser direct infrared (LDIR) analysis were used for the qualitative analysis of microplastics. The μ‐FT‐IR and LDIR analyses revealed the presence of large quantities of microplastics in the settled dust. The samples were composed of cellulose, polyethylene terephthalate, polyethylene, alkyd resins, polysulfone, polyvinyl alcohol, and polyamides. The μ‐FT‐IR and LDIR analyses were suitable for identifying large fibrous materials and small particles, respectively. Thus, the two methods are complementary for the comprehensive identification of microplastic composition in settled dust. [ABSTRACT FROM AUTHOR]

Electrochromic (EC) smart windows offer a promising paradigm for intelligent control of heat and light, reducing ≈40% building‐energy expenses, which are widely expected as a key contributor to future global carbon neutrality and sustainability. Enabling arbitrarily shaped EC film devices can unlock promising capabilities in various smart building systems and intelligent color‐changeable wearable devices. Regrettably, their wide deployment has been largely limited by the complicated edge encapsulation processes; otherwise, the leakage/loss of electrolyte and environmental corrosions would rapidly lead to device failure. This article reports a blood coagulation‐analogous strategy to tackle this critical challenge by introducing an oxygen‐sensitive prepolymer (i.e., alkyd resin) as the electrolyte additive, making it free of packaging. When exposed to the air, this prepolymer can rapidly cure and form a dense solid barrier through a free radical reaction with the CH bond on the 1,4‐diene side chains, without sacrificing any EC performances, including excellent mechanical flexibility and robustness. Besides the fast self‐packageable and arbitrarily tailorable capabilities, they can also deliver outstanding environmental‐stability after harsh aging. This mechanism potentially makes large‐scale customized production and thus the application of EC devices become possible and may significantly boost the broad application of such a sustainable and fashionable technology. [ABSTRACT FROM AUTHOR]

The paper studied the influence of a catalyst, comparing it with its traditional counterparts, in the process of obtaining a polyethylene terephthalate (PET)-based alkyd resin from post-consumer beverage bottles and how it consumes raw materials and generates waste. The resin was obtained in two phases: (1) glycerol and soybean oil alcoholysis reaction, a renewable material, for polyalcohol production, and (2) polyalcohol and polyacid esterification reaction to obtain the alkyd resin (reaction via solvent). A lithium octoate catalyst (OctLi) was used, not traditional in the alcoholysis reaction, and a fraction of the polyacid replaced by post-consumer PET at a proportion of up to 24% by weight in the esterification reaction. The OctLi catalyst caused a reaction in 30 min, compared to zinc acetate (120 min) and lithium hydroxide (LiOH, 60 min). Using post-consumer PET in obtaining the alkyd resin also decreased the esterification reaction time by 22% (8% PET), 67% (16% PET) and 72% (24% PET), compared to esterification without PET. The reaction time, considering alcoholysis with OctLi and partial esterification with PET (with 24% PET), was 180 min. Adding alcoholysis time with the LiOH catalyst and esterification without PET raises the reaction time to 600 min. Process water formed during the esterification stage declined by 15% (8% PET), 50% (16% PET) and 77% (24% PET), compared to the reaction without PET. The shorter reaction time resulted in less equipment use and consequent lower energy consumption. Another result was that the alkyd resin obtained with 8% PET was adequate for paint formulations. [ABSTRACT FROM AUTHOR]

Two non-isocyanate polyurethanes (NIPUs) were used as reactive diluents for an alkyd to obtain eco-friendly new UV-curable alkyd-polyurethane coatings. A linseed-based alkyd resin was prepared and formulated with the reactive diluents (NIPUs) and free radical photoinitiator, and then UV-cured. NMRs were used to characterize the alkyd and NIPUs and glass transition temperature (Tg) of cured alkyd-polyurethanes were evaluated by using DSC. Further, spectroscopy and thermal stability of the coatings were evaluated by using ATR-IR spectroscopy and thermogravimetric analysis (TGA), respectively. Moreover, coating properties such as pencil hardness, cross-cut adhesion, pull-off adhesion, impact resistance, and reverse impact resistance were also evaluated. It was found that crosslink density, pencil hardness, adhesion, and Tg were dependent and proportional to the amount of the NIPUs (reactive diluents) showing significant improvement in mechanical and thermal properties compared to the linseed-based alkyd resin. [ABSTRACT FROM AUTHOR]

Novel phosphorylated cardanol molecules based on phosphonate (PO3CR) and phosphate (PO4CR) functions were synthetized. Those molecules have two main actions which are described in this article: the reduction in volatile organic compounds (VOC) and the development of flame retardant (FR) properties conferred on alkyd resins used as coatings for wood specimen. Phosphorylated cardanol compounds have been successfully grafted by covalent bonds to alkyd resins thanks to an auto-oxidative reaction. The impact of the introduction of PO3CR and PO4CR on the film properties such as drying time and flexibility has been studied and the thermal and flame retardant properties through differential scanning calorimeter, thermogravimetric analysis and pyrolysis-combustion flow calorimeter. These studies underscored an increase in the thermal stability and FR properties of the alkyd resins. In the cone calorimeter test, the lowest pHRR was obtained with 3 wt% P of phosphate-cardanol and exhibited a value of 170 KW.m−2, which represented a decrease of almost 46% compared to the POxCR-free alkyd resins. Moreover, a difference in the mode of action between phosphonate and phosphate compounds has been highlighted. The most effective coating which combined excellent FR properties and good coating properties has been obtained with 2 wt% P of phosphate-cardanol. Indeed, the film properties were closed to the POxCR-free alkyd resin and the pHRR decreased by 41% compared to the reference alkyd resin. [ABSTRACT FROM AUTHOR]

The widely used alkyd resin suffers not only the flammability but also the autoignition of resin waste. Its autoignition should result from the air-drying exothermic effect due to autoxidation and conversion of double bond. However, the air-drying exothermic effect is seldom studied. In this study, five soybean oil-based alkyd resins were synthesized. The content of double bond measured by the titration method increased linearly with increasing the molar fraction of maleic anhydride. After air-drying, the infrared spectroscopy absorption peak for the double bond disappeared. Considering that the curing originated from the conversion of chemical bonds, the exothermic effect was theoretically analyzed to be 1163–1455 kJ mol−1 double bond based on the air-drying mechanisms and the differences among chemical bond energies. According to thermodynamics principles, the air-drying exothermic effect was also derived from the measured heat of combustion. When the content of double bond increased from 2.19 mol kg−1 resin to 2.56 mol kg−1 resin, the exothermic effect linearly increased from 1352 kJ mol−1 double bond or 2.96 kJ g−1 resin to 2508 kJ mol−1 double bond or 6.42 kJ g−1 resin. The steady and unsteady autoignition theoretical analyses implied that due to the air-drying exothermic effect the alkyd resin waste with a certain thickness would catch fire within one working day. [ABSTRACT FROM AUTHOR]

The aim of the present study was to perform morphological and chemical characterizations of microplastics (MPs) found in seawater samples from the coast of the city of Fortaleza (CE) using Fourier-transform infrared (FTIR) spectroscopy, Raman spectroscopy and differential scanning calorimetry (DSC). Sampling was performed using a neuston sampler. MPs were separated based on the difference in density. MPs with varied morphologies were found. Fibers and fragments were the most abundant (57% and 36.2%, respectively). FTIR, Raman spectroscopy and DSC confirmed the presence of polyurethane and alkyd resin, polyethylene, polypropylene, polystyrene, polyamide blends, thermoplastic rubber and polyester fibers. The main sources of MPs and their relative contribution were fishing activities, food packaging and household products with 55.1%, household laundry with 27.2%, wear of surface coatings with 10.0% and wear of automobile tires with 7.6%. As a result, polyethylene, polypropylene, polystyrene and polyamide are believed to enter the marine environment mainly through fishing activities and debris from food packaging, polyester mainly through domestic sewage contaminated by washing clothes fibers, polyurethane and alkyd resin from the abrasive wear of surface coatings, as well as rubber particles from the wear of the automobile tires. Thus, one may infer that the main sources of MPs in the marine environment on the coast of Fortaleza are anthropogenic activities. Additionally, there is less information on blends and weathered MPs in commercial polymer databases. Therefore, the MP spectra obtained in this study can serve as a database to compare and characterize these more complex MPs. [ABSTRACT FROM AUTHOR]

This study reports promising catalytic activity of oxidovanadium(IV) dialkyl phosphates those can serve as primary driers for air-drying paints and as accelerators for room-temperature curing of unsaturated polyester resins. It describes an improved synthetic protocol giving title compounds at high yields and clarifies their molecular structure. The behavior in solution and in formulation of alkyd resin was investigated by electron paramagnetic resonance. Strong catalytic activity is documented by standard tests on several commercial alkyd binders and one multipurpose unsaturated polyester resin. [Display omitted] • Vanadium-based drier/accelerator synthesized and fully characterized • Catalytic activity in alkyd resins and unsaturated polyesters established • Cured films showing promising mechanical properties • Example of cobalt-free technology reported [ABSTRACT FROM AUTHOR]

Homemade screen-printed electrodes (SPEs) were produced using conductive inks with graphite and alkyd resin and were modified with electropolymerized films of polyaniline (PAni) grafted with 2.5 and 5.0 (m:m) of graphene oxide (GO) obtained by the chemical oxidation of graphite. The SPEs were characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The CV results showed similar redox behavior for all SPE, characteristic of PAni films in an acidic medium (0.5 mol L−1 H2SO4). However, the EIS results showed a decrease in the charge-transfer resistance (Rct), from 1064 Ω for SPE/PAni to 364 Ω for SPE/PAni-2.5%GO (about 3 times) and to 113 Ω for SPE/PAni-5%GO (about 10 times) compared to the unmodified counterpart SPE/PAni. Additionally, an increase in the constant phase element (CPE2) value was also observed, from 459 µS sα cm−2 for SPE/PAni to 838 µS sα cm−2 for SPE/PAni-2.5%GO and to 1560 µS sα cm−2 for SPE/PAni-5%GO, indicating lower ion transport for the SPEs modified with the PAni-GO hybrids. This method to produce a homemade SPE modified with the PAni-GO hybrid with improved electrochemical behavior and ionic conductivity is a simple, low-cost, scalable, and interesting alternative for future applications in sensors or charge-storage electrochemical devices.Graphical Abstract: Homemade screen-printed electrodes (SPEs) were produced using conductive inks with graphite and alkyd resin and were modified with electropolymerized films of polyaniline (PAni) grafted with 2.5 and 5.0 (m:m) of graphene oxide (GO) obtained by the chemical oxidation of graphite. The SPEs were characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The CV results showed similar redox behavior for all SPE, characteristic of PAni films in an acidic medium (0.5 mol L−1 H2SO4). However, the EIS results showed a decrease in the charge-transfer resistance (Rct), from 1064 Ω for SPE/PAni to 364 Ω for SPE/PAni-2.5%GO (about 3 times) and to 113 Ω for SPE/PAni-5%GO (about 10 times) compared to the unmodified counterpart SPE/PAni. Additionally, an increase in the constant phase element (CPE2) value was also observed, from 459 µS sα cm−2 for SPE/PAni to 838 µS sα cm−2 for SPE/PAni-2.5%GO and to 1560 µS sα cm−2 for SPE/PAni-5%GO, indicating lower ion transport for the SPEs modified with the PAni-GO hybrids. This method to produce a homemade SPE modified with the PAni-GO hybrid with improved electrochemical behavior and ionic conductivity is a simple, low-cost, scalable, and interesting alternative for future applications in sensors or charge-storage electrochemical devices. [ABSTRACT FROM AUTHOR]

Hundreds of studies have surveyed plastic debris in surface ocean gyre and convergence zones, however, comprehensive microplastics (MPs, ≤5 mm) assessments beneath these surface accumulation areas are lacking. Using in situ high‐volume filtration, Manta net and MultiNet sampling, combined with micro‐Fourier‐transform‐infrared imaging, we discovered a high abundance (up to 244.3 pieces per cubic meter [n m−3]) of small microplastics (SMPs, characteristically <100 μm) from the surface to near‐sea floor waters of the remote South Atlantic Subtropical Gyre. Large horizontal and vertical variations in the abundances of SMP were observed, displaying inverse vertical trends in some cases. SMP abundances in pump samples were more than two orders of magnitude higher than large microplastics (LMPs, >300 μm) concurrently collected in MultiNet samples. Higher‐density polymers (e.g., alkyd resins and polyamide) comprised >65% of the total pump sample count, highlighting a discrepancy between polymer compositions from previous ocean surface‐based surveys, typically dominated by buoyant polymers such as polyethylene and polypropylene. Contrary to previous reports stating LMP preferentially accumulated at density gradients, SMP with presumably slower sinking rates are much less influenced by density gradients, thus resulting in a more even vertical distribution in the water column, and potentially longer residence times. Overall, our findings suggest that SMP is a critical and largely underexplored constituent of the oceanic plastic inventory. Additionally, our data support that weak current systems contribute to the formation of SMP hotspots at depth, implying a higher encounter rate for subsurface particle feeders. Our study unveils the prevalence of plastics in the entire water column, highlighting the urgency for more quantification of the deep‐ocean MP, particularly the smaller size fraction, to better understand ecosystem exposure and to predict MP fate and impacts. [ABSTRACT FROM AUTHOR]

Modification of existing paints and varnishes based on alkyd and melamine alkyd resins as well as creation of new film formers with the help of functionalized oligomers in order to improve the properties of materials during their operation was carried out. Liquid oligobutadiene rubber wiThend hydroxyl groups, HTPB trend mark was used. Pentaphthalic varnish PF-060 and melamine-formaldehyde resin K-421-02 was modified by triisocyanate oligobutadiene rubber based on trimethylolpropane and isophorone diisocyanate resin in different ratios. Analysis of the FTIR spectra of the developed paints and varnishes showed that the process of polymerization in a thin film in air forms a spatially crosslinked polymer and passes through the stage of formation of branched soluble polymers, followed by copolymerization of components with oxygen and formation of structured solid polymer. The optimal content of rubber in the modified paints and varnishes was estimated. For alkyd varnish PF-060 it equals 10 wt.% and for melamine-formaldehyde resin K-421-02 is in the range 7-10 wt.%. Addition of triisocyanate accelerates the drying process of coatings on air, high values of surface hardness, adhesion, resistance to bending and water absorption were also received. Developed modified paints and varnishes are characterized by increased viability, shelf life of more than 6 months, homogeneity. Proposed scheme allows to obtain transparent coatings with high physical and mechanical characteristics and can be recommended for practical use in various coating technologies. [ABSTRACT FROM AUTHOR]

Nowadays, the use of non-edible vegetable oils as the raw material for polymer development is growing in interest because of the scarcity and high demand for crude oil and also because of its eco-friendly approach. The utilization of non-edible oil to synthesize the applicable polymers reduces the usage of petrochemicals. To eliminate the reliance on petrochemicals, it is important to search for and extract alternate and domestic non-edible oils suitable for the synthesis of polymeric materials. This is now a promising research approach. The outstanding feature of indigenous, non-edible Madhuca indica oil (MO) is its chemical structure, with unsaturated sites and esters that are considerable ingredient polyols for the development of polymers. This review discusses the origin, structure and extraction of MO and systematically focuses on the recently developed polymers using oil as a renewable source of polyols. We have briefly reviewed MO-based polymeric materials such as alkyd resins like pentaalkyds for scratch resistance, glycerol alkyds for fly-ash coating, pentalkyd LC resins for display coating applications and epoxies of MO for biological coating materials. Also, the important polyurethanes in the pathways of MO-based fatty amide are transformed into the polyetherimide polyols through a step-growth reaction with bisphenol-A or bisphenol derivatives, which again react with isocyanates to produce MO-based PU for excellent adhesion and coating applications. Another type of waterborne polyurethane is made from polyesteramides. These PU coatings are used in the paint and pigment industries. We reviewed their synthesis and widespread use in coatings and composites. [ABSTRACT FROM AUTHOR]