Fluorinated non-isocyanate polyurethanes coatings

Researchers from China synthesized two different cyclic carbonates, bisphenol AF (EC-AF) and perfluorooctyl cyclic carbonate (PFGC), respectively, in order to improve the chemical resistance of non-isocyanate polyurethane (NIPU). After synthesis of these cyclic carbonates, fluorine-containing non-isocyanate polyurethane coatings were prepared and the effects of PFGC amounts on the properties of NIPU were studied. It was found that the contact angles of water, diiodomethane, and hexadecane … Continue reading Fluorinated non-isocyanate polyurethanes coatings

Nanoparticle self-migration to obtain wear-resistant UV-curing antibacterial coatings

Researchers from China revealed the fabrication of a robust and wear-resistant polyurethane-based coatings via the addition of fluoro-containing quaternary ammonium compounds (QACF) modified silica nanoparticles. A classical Stöber process was used to obtain nanoparticles with a thin layer of thiol groups on the particle surface. Then, through double bond and thiol group reaction, QACF is then further linked to the particle surface. It was shown that QACF and … Continue reading Nanoparticle self-migration to obtain wear-resistant UV-curing antibacterial coatings

Heat-cured thermoset coatings from non-isocyanate polyurethane polyols

Researchers synthesized a series of novel polyurethane polyols using cyclic carbonate/polyamine chemistry with varying hydroxyl content and molecular weights and evaluated them for thermosetting coating applications. An amino resin crosslinker in varying amounts was used in order to investigate the mechanical properties of the obtained coatings. It was shown that the adhesion to the substrate was improved with higher urethane content in the backbone. Moreover, … Continue reading Heat-cured thermoset coatings from non-isocyanate polyurethane polyols

Integrated antibacterial and antifouling properties of mixed polymer brushes

Researchers from China designed and synthesized a series of mixed polymer brushes grafted from silica surface as a new type of antibiofouling and antimicrobial coating, which combine poly(N-hydroxyethyl acrylamide) (polyHEAA) synthesized by atom transfer radical polymerization (SI-ATRP) and cationic poly(trimethylamino) ethyl methacrylate chloride, polyMETAC) synthesized by photoiniferter-mediated polymerization (SI-PIMP). By tuning ATRP and PIMP initiator ratios, the surface composition, charge and morphology of the resultant … Continue reading Integrated antibacterial and antifouling properties of mixed polymer brushes

Anti-soiling performance of transparent superhydrophilic and superhydrophobic nanoparticle textured coatings

Researchers investigated the anti-soiling (AS) performance of highly reflective, superhydrophilic (SPH, 0° water contact angle) and superhydrophobic (SP, >165° water contact angle)coated mirrors. A simple one-step nanotextured silica nanoparticle coating on a mirror exhibited SPH properties associated with hydrophilic rough surfaces while another mirror surface post-functionalized with low-surface-energy ligand molecules displayed SP behavior. ıt was found in daily degradation in solar reflectance induced by dust accumulation … Continue reading Anti-soiling performance of transparent superhydrophilic and superhydrophobic nanoparticle textured coatings

Novel renewable tung oil-based UV-curable active monomers and bio-based copolymers

Researchers from China synthesized two kinds of tung-oil-derived renewable UV-curable active monomers, tung-acid-maleic tri-acrylate (TOAH) and tung-maleic tetra-acrylate (TMPG) and investigated UV-curing kinetics of the films by Photo-DSC, thermal properties of their cured films by dynamic mechanical analysis, mechanical properties by tensile tests and general performance of UV-curing films by acidic, alkaline resistance and boiling-water resistance tests. Dynamic mechanical analysis showed that the storage modulus … Continue reading Novel renewable tung oil-based UV-curable active monomers and bio-based copolymers

Self-assembled tetraaniline nanofiber as a novel anticorrosive pigment for waterborne epoxy coatings

Researchers from China synthesized the self-assembled tetraaniline nanofiber in 1 M HCl solution and investigated the the addition of tetraaniline based conducting nanofiber (TANF) on the anticorrosive properties of waterborne epoxy coatings on Q235 mild steel. ıt was found out that the self-assembled TANF possesses excellent solubility, tiny nanofibrous structure and reversible redox behavior. The anticorrosion performance of epoxy coating with and without self-assembled tetraaniline nanofiber … Continue reading Self-assembled tetraaniline nanofiber as a novel anticorrosive pigment for waterborne epoxy coatings

Controlled release of corrosion inhibitors in self-healing coatings: Tannic complexes coated nanocontainers

Researchers encapsulated corrosion inhibitor in mesoporous silica nanoparticles (MSNs) with the help of tannic acid complexes which provide the inhibitor loaded MSNs with pH-controlled release function. Then, 2 wt% of benzotriazole-loaded nanocontainers were impregnated to commercial water-borne alkyd coating and self-healing effect after 20 days of immersion in 0.1 M NaCl solution was investigated by electrochemical impedance spectroscopy and microscopy. The results showed that the impedance modulus of coating with nanocontainers increased from 4.7 × 104 Ω cm2 to 1.8 × 105 Ω cm2 after … Continue reading Controlled release of corrosion inhibitors in self-healing coatings: Tannic complexes coated nanocontainers

Polyaniline coated core-shell polyacrylates for corrosion protection

Researchers synthesized aqueous polymer colloidal nanoparticles, composed by poly(methyl metacrylate), butyl acrylate, and acrylic acid, as “core” (P(MMA/BA/AA)); and polyaniline (PAni) doped with dodecylbenzenesulfonic acid (DBSA), as “shell” in order to investigate corrosion protection of metal. Free radical emulsion polymerization, followed by a second step where the chemical oxidative polymerization of aniline monomers upper the “core” surfaces was used in the synthesis. The results showed … Continue reading Polyaniline coated core-shell polyacrylates for corrosion protection

Anti-corrosion behavior of epoxy composite coatings containing molybdate-loaded mesoporous silica

Abstract In this study, mesoporous silica nanocontainers (MS) were successfully synthesized, functionalized and loaded with sodium molybdate as a corrosion inhibitor (MSInh). The epoxy composite coatings were applied on the mild steel substrates by embedding 1 wt. % mesoporous silica with (E/MSInh) or without (E/MS) inhibitor. Characterization of the synthesized mesoporous silica loaded with molybdate demonstrated the pH-dependence of molybdate release from E/MSInh. According to the results, by … Continue reading Anti-corrosion behavior of epoxy composite coatings containing molybdate-loaded mesoporous silica

UV/thermal dual curing of tung oil-based polymers induced by cationic photoinitiator

Abstract With the increasing shortage of petroleum-based resources, the exploitation and application of the polymers derived from the renewable resources has becomes increasingly important for the industrial development. In this work, in order to promote the direct application of tung oil in the coating field, the tung oil-based polymers with the excellent mechanical properties by using cationic photoinitiator as the “green” initiator were prepared. The … Continue reading UV/thermal dual curing of tung oil-based polymers induced by cationic photoinitiator

Antimicrobial activities of low molecular weight polymers synthesized through soap-free emulsion polymerization

Abstract To evaluate the influence of low molecular weight polymers synthesized through soap-free emulsion polymerization on the indicator microorganism, Micrococcus luteus, methyl methacrylate (MMA) and styrene were polymerized by using various initiators. The MMA polymer colloid was not toxic to M. luteus. High volumes of polystyrene were continuously synthesized, and low-molecular weight polystyrenes were removed from the suspension to the supernatant. During the bioassay test, as the … Continue reading Antimicrobial activities of low molecular weight polymers synthesized through soap-free emulsion polymerization

Robust alkyd/exfoliated graphene oxide nanocomposite as a surface coating

Abstract Design of advanced nanostructured coatings with ecofriendly character and highly branched structure has been given a particular attention. In this work, we developed a novel robust alkyd/exfoliated graphene oxide (GO) nanosheets composite coating via solution casting. Alkyd matrix with hyperbranched moiety was developed via polyesterification of sunflower oil and polyester. Hyperbranched polyester was facilely synthesized via A2 and B3 technique. Exfoliated GO with 0.5–2 nm sheet thickness … Continue reading Robust alkyd/exfoliated graphene oxide nanocomposite as a surface coating

Preparation, Structure, and Properties of Surface Modified Graphene/Epoxy Resin Composites for Potential Application in Conductive Ink

Abstract The dispersity of graphene (GE) in the matrix has an important influence on the thermal, mechanical, and electrical properties of its derived composites. In this paper, surface modification with a silane coupling agent and a double injection method were used to improve the dispersity of GE in epoxy resin (EP). The thermal, mechanical, and electrical properties of modified graphene/epoxy resin composites (modified GE/EP) were … Continue reading Preparation, Structure, and Properties of Surface Modified Graphene/Epoxy Resin Composites for Potential Application in Conductive Ink

Role of Moisture in the Failure of Coatings on Wood

Abstract Most wood coating tests are done either in a short term artificial weathering chamber or long term on an outdoor rack/fence. In both cases, the coatings are exposed to both ultraviolet radiation and water. This study is focused on the influence of moisture alone on wood opaque film forming coating failures. As moisture is sorbed into the wood structure, the wood swells in proportion … Continue reading Role of Moisture in the Failure of Coatings on Wood

Edible Films and Coatings for Fresh Fish Packaging: Focus on Quality Changes and Shelf-life Extension

Abstract Fresh fish is extensively consumed and is one of the most-traded food commodities in the world. Conventional preservation technologies include vacuum and modified atmosphere packaging, but they are costly since requires capital investment. In the last decade, research has been directed towards the development of antimicrobial packaging systems, as an economical alternative to these. This paper outlines antimicrobial films and coatings applied so far … Continue reading Edible Films and Coatings for Fresh Fish Packaging: Focus on Quality Changes and Shelf-life Extension

Reduced Graphene Oxide Reinforced Waterborne Soy Alkyd: Formulation, Characterization and Corrosion Inhibition Analysis

Researchers synthesized the waterborne soya alkyd (WSA), in which soya oil monoglyceride was used as a precursor, and its RGO dispersed nanocomposites (WSA-RGO) via ex-situ polymerization using solvent-less green approach. The synergistic effect of nano-fillers and poly melamine co-formaldehyde isobutylated solution modified organic matrix (WSA) on physico-mechanical and corrosion inhibition of these coatings on finally polished carbon steel (CS) was investigated. The results revealed that the nanocomposite coatings … Continue reading Reduced Graphene Oxide Reinforced Waterborne Soy Alkyd: Formulation, Characterization and Corrosion Inhibition Analysis

The thermal self‐healing phenolic polyurethane derived from polyphenols

Researchers investigated the effects of polyphenols with different substituents, namely propyl gallate, catechol, and tert‐butylhydroquinone, on the selfhealing performance of polyurethanes. Polyurethanes with different polyphenols were synthesized and their self-healing abilities were characterized. Variable‐temperature FT‐IR spectra revealed that PTHFTDI‐Propyl gallate with electron‐withdrawing substituent exhibited the lowest decomposition and healing temperatures while TGA displayed that PTHFTDI‐Urushiol with electron‐donating substituent exhibited the best thermostability.  At the same temperature, the healing abilities of the … Continue reading The thermal self‐healing phenolic polyurethane derived from polyphenols

A Self-healable and Catalyst-free Epoxy Vitrimer System

Vitrimers are derived from thermosetting polymers and a class of plastics. In order to achieve the dynamic transesterification reaction (TER), all epoxy vitrimer systems described in the literature rely on the addition of significant amounts of catalysts until now. The catalysts used in vitrimers have some drawbacks such as being toxic, poor miscibility with organic compounds and causing corrosion resistance. Therefore, researchers first synthesized hyperbranched epoxy (HBE) prepolymers and then reacted with succinic anhydride … Continue reading A Self-healable and Catalyst-free Epoxy Vitrimer System

Corrosion resistance of graphene sheets with different structures in waterborne epoxy coatings

Although it was reported earlier that graphene can be used for corrosion protection, the effects of different structures were not investigated. Researchers from China investigated the effects of graphene sheets with four structures in waterborne epoxy coatings, named EP-Ga, EP-Gb, EP-GO and EP-GS. Potential, impedance testing and Tafel curves were used for characterization of the corrosion behaviours of coatings. It was found that EP-Ga composite coating could possess … Continue reading Corrosion resistance of graphene sheets with different structures in waterborne epoxy coatings

A Review of Conductive Metal Nanomaterials as Conductive, Transparent, and Flexible Coatings, Thin Films, and Conductive Fillers: Different Deposition Methods and Applications

With ever-increasing demand for lightweight, small, and portable devices, the rate of production of electronic and optoelectronic devices is constantly increasing, and alternatives to the current heavy, voluminous, fragile, conductive and transparent materials will inevitably be needed in the future. Conductive metal nanomaterials (such as silver, gold, copper, zinc oxide, aluminum, and tin) and carbon-based conductive materials (carbon nanotubes and graphene) exhibit great promise as … Continue reading A Review of Conductive Metal Nanomaterials as Conductive, Transparent, and Flexible Coatings, Thin Films, and Conductive Fillers: Different Deposition Methods and Applications

2-aminobenzothiazole as an antimicrobial agent for waterborne polyurethane dispersions (WPUDs)

Nowadays, the use of antimicrobial coatings is increasing in many different applications. Researchers incorporated aminobenzothiazole (ABT) on the backbone of waterborne polyurethane in the chain extension process in order to obtain antimicrobial coatings. First of all, itaconic acid and 1,6-hexanediol based polyol was synthesized and then it was reacted with dimethylol propionic acid and isophoronediisocyanate to form a prepolymer. The prepolymer obtained was neutralized with triethylamine and 1,4-butanediol … Continue reading 2-aminobenzothiazole as an antimicrobial agent for waterborne polyurethane dispersions (WPUDs)

Polyurethane-based microcapsules containing bulky-IPDI-BA and nano-clay for self healing

Researchers prepared polyurethane-based microcapsules filled with bulky isophorone diisocyanate, IPDI via interfacial polymerization method in an oil-in-water emulsion and then investigated mechanical properties and self-healing ability of microcapsule-embedded polyurethane, PU, coating. The standard salt spray test method was used to analyze the healing ability of microcapsules within the PU coatings while the crack healing properties of the PU coatings was defined using SEM micrographs. Results revealed that … Continue reading Polyurethane-based microcapsules containing bulky-IPDI-BA and nano-clay for self healing

Effect of Adding UV Absorbers Embedded in Carbonate Calcium Templates Covered with Light Responsive Polymer into a Clear Wood Coating

The limited durability of clear coatings is a major issue for the coating and wood industry. The addition of organic UV absorbers improves coating resistance by the absorption and the conversion of the UV radiation into harmless heat. Organic UVAs are prone to degradation and can migrate in the binder of coatings. In this study, commercial UVAs and HALS have been entrapped into CaCO3 templates coated … Continue reading Effect of Adding UV Absorbers Embedded in Carbonate Calcium Templates Covered with Light Responsive Polymer into a Clear Wood Coating

Cross-linked Polyurea Spray Coatings

Spray coated polyurea applications are increasing, owing to ease of application, adhesive properties, rapid cure time and excellent mechanical properties, in niche areas compared to traditional coatings. Researchers from India investigated the effects of cross-linking on spray-coated polyurea. For this purpose, a long chain trifunctional amine was used from 0 to 3.5 mol % as a co-reactant in the resin blend. It was shown that cross-linking … Continue reading Cross-linked Polyurea Spray Coatings

A waterborne graphene-poly(urethane-acrylate) for anticorrosive coatings

Researchers prepared waterborne graphene/polymer nanocomposite by incorporation of cationic graphene (CGR) in anionic poly(urethane-acrylate) (WPUA) prepolymer. The results revealed that the water resistance, tensile strength and anticorrosive properties are significantly increased compared to control sample. Moreover, it was found that the impedance modulus and coating resistance of 0.5% CGR-WPUA are of the same order before and after immersion. Long-term anticorrosive properties of CGR-WPUA were superios … Continue reading A waterborne graphene-poly(urethane-acrylate) for anticorrosive coatings

Polyaniline/zinc/cerium nitrate composites as anticorrosion pigments for epoxy coatings

Researchers from China synthesized polyaniline (PANI) microspheres by self-assembly method in poly (2-acrylamido-2-methylpropane sulfonic acid) (PAMPS) aqueous solution and then Ce3+ ions were doped onto PANI hollow microspheres and further blended with Zn particles to prepare polyaniline/zinc/cerium nitrate composites. Prepared composites were used as additives in epoxy resin and dispersed in resin by mechanical grinding. Anticorrosion experiments  revealed that impedance value in low frequency region maintained at 106 Ω·cm2 after 70 days … Continue reading Polyaniline/zinc/cerium nitrate composites as anticorrosion pigments for epoxy coatings

A New Class of Coating Material: Self-Healable and Ultrahydrophobic Polyurethane-POSS Hybrids

Researchers from India first functionalized polyurethane using a novel chain extender (FA-FGE) which was obtained from the reaction between furfurylamine (FA) and furfuryl glycidyl ether (FGE) and then Diels–Alder (DA) “click” reaction was used to graft this functionalized PU with maleimide functionalized polyhedral oligomeric silsesquioxanes (POSS maleimide isobutyl, POSS-M). Water contact angle (WCA) of this DA adducts was increased from 84° to 141.3°. Moreover, it was found that the tensile strength … Continue reading A New Class of Coating Material: Self-Healable and Ultrahydrophobic Polyurethane-POSS Hybrids

Epoxy Nanocomposite Toughened with Silanized Fullerene

Researchers investigated the effects of fullerene (C60) on the mechanical properties of epoxy nanocomposites. For this purpose, Fullerene (C60) was oxidized first and then silanized using 3-Aminopropyltriethoxysilane (APTES).  It was claimed that The formation of active functional groups on silanized C60 regulated the polymer assembly and its coordination that enhances scratch recovery index (~32%), wear resistance (~57%) and microhardness (~19 %) of epoxy composites. When silanized C60 was used … Continue reading Epoxy Nanocomposite Toughened with Silanized Fullerene

Functionalized Ceramic Particles in Coatings for Improved Scratch Resistance

The top layer of a typical high pressure floor laminate (HPL) consists of a melamine formaldehyde (MF) impregnated special wear layer (overlay) with alumina particles. This top layer plays a crucial role in determining the mechanical properties of the laminate. For HPLs, scratch resistance and scratch visibility are particularly important properties. This study aimed to improve the mechanical properties, particularly the scratch resistance, by adjusting … Continue reading Functionalized Ceramic Particles in Coatings for Improved Scratch Resistance