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This paper aims to prepare a new donor–π–acceptor (D–π–A) and acceptor–π– D–π–A (A–π–D–π–A) phenothiazine (PTZ) in conjugation with vinyl isophorone (PTZ-1 and PTZ-2) were designed and their molecular shape, electrical structures and characteristics have been explored using the density functional theory (DFT). The results satisfactorily explain that the higher conjugative effect resulted in a smaller high occupied molecular orbital–lowest unoccupied molecular orbital gap (Eg). Both compounds show intramolecular charge transfer (ICT) transitions in the ultraviolet (UV)–visible range, with a bathochromic shift and higher absorption oscillator strength, as determined by DFT calculations.

The produced PTZ-1 and PTZ-2 sensors were characterized using various spectroscopic methods, including Fourier-transform infrared spectroscopy and nuclear magnetic resonance spectroscopy (¹H/¹³CNMR). UV–visible absorbance spectra of the generated D–π–A PTZ-1 and A–π–D–π–A PTZ-2 dyes were explored in different solvents of changeable polarities to illustrate positive solvatochromism correlated to intramolecular charge transfer.

The emission spectra of PTZ-1 and PTZ-2 showed strong solvent-dependent band intensity and wavelength. Stokes shifts were monitored to increase with the increase of the solvent polarity up to 4122 cm⁻¹ for the most polar solvent. Linear energy-solvation relationship was applied to inspect solvent-dependent Stokes shifting. Quantum yield (ф) of PTZ-1 and PTZ-2 was also explored. The maximum UV–visible absorbance wavelengths were detected at 417 and 419 nm, whereas the fluorescence intensity was monitored at 586 and 588 nm.

The PTZ-1 and PTZ-2 dyes leading to colorimetric and emission spectral changes together with a color shift from yellow to red.

The purpose of this work was to prepare a catalyst-free microcapsules as self-healing agent in an automotive clearcoat to improve the scratch resistance of coatings.

In this research, microcapsule with isophorone diisocyanate (IDPI) core and polyurethane shell were prepared and used in self-healing coatings. Microcapsules synthesised were characterised by thermal gravimeter and infrared spectra. The microcapsules were dispersed in an acrylic-melamine clearcoat, and the scratch resistance was evaluated.

The triplex product and the formed polyurethane bonds were confirmed by thermal gravimeter and infrared spectra. In addition, smooth spherical particles with a diameter of 1.5 to 1.7 micronmeters were observed by a scanning electron microscope. The microcapsules dispersed in an acrylic-melamine clearcoat increased the scratch resistance of coatings. Also, the self-healing feature of those coatings was proved.

The size of microcapsules can affect its dispersion in the clearcoat and consequently affect the properties of the cured films.

The self-healing coatings are interested for many industries such as building and automotive industries. The reported data can be used by the formulators working in the R & D departments.

Self-healing systems are considered as one of the smart coatings. Therefore, the developing of its knowledge can help to extend its usage to different applications.

The application of microcapsules in the coating as healing agents is a great challenge, which has been hardly investigated so far. In the current research, the effect of polyurethane-IDPI microcapsules in an automotive clearcoat as a self-healing coating was investigated.

Three Jotun Paints coating systems — “Barrier/Navitar”, “Marathon” and “Baltoflake” — have been tested for abrasion resistance by BAW (Bundesanstalt für Wasserbau), the official German approvals authority for sub‐merged steel structures in harbours, canals and sluices. As a result, all three systems have been approved by BAW.

Urethane Acrylate Oligomer with 100% solids was synthesised and characterised in order to study the application in electron beam curing with varying ratio of Trimethylol propane triacrylate (TMPTA). The purpose of this paper is to study effect of TMPTA addition on the crosslink density and different coating properties.

Polyester polyol was synthesised by reacting single diacid, adipic acid (AA), with Pentaerythritol (PENTA) and 1,6‐hexanediol (HD). Further, Urethane acrylate resin was synthesised by using Isophorone diisocyanate (IPDI), hydroxy ethyl acrylate (HEA) and Polyester polyol. The polyester polyol and urethane acrylate oligomer were characterised by 1H NMR, 13C NMR, FTIR and GPC. Further, TMPTA was added as a crosslinker to the urethane acrylate oligomer and cured by electron beam radiation. The cured UA films having varying concentration of TMPTA were employed to evaluate thermal property, contact angle analysis, mechanical and chemical properties.

The obtained results showed improvement in their chemical properties, mechanical properties, thermal properties and water contact angle at 20% of TMPTA iconcentration. The TMPTA also reduced the dose required for the curing.

The resin can be synthesised from different isocyanates as TDI, MDI and HMDI, etc. The study can also be done with different multi or mono functional monomers such as methacrylate, hexanediol diacrylate, ethylene glycol diacrylate, etc.

The paper provides the better solution to reduce the cost of the electron beam radiation required for the curing.

The method presented in the paper could be very useful for controlling environmental pollution; as the conventional method of curing releases volatile organic compounds (VOC).

In this paper, urethane acrylate and TMTPA cured with electron beam are shown to offer good coating properties. A high‐solid urethane acrylate coating would find numerous industrial applications in surface coatings.

The study aims to synthesise polyurethane dispersion from polyesteramide polyol. The polyesteramide polyol is a novel polyol for the synthesis of polyurethane dispersion.

Polyesteramide polyol has been synthesised from phthalic anhydride and fatty amide of mustard oil. Aminolysis of mustard oil had been carried out with diethanolamine. The novel polyurethane dispersion had been synthesised using a polyesteramide polyol as a precursor. Isophorone diisocyanate was used as an isocyanate component and polyurethane dispersion (PUDs) had been synthesised by an anionic method where DMPA was introduced to introduce –COOH groups as via grafting to the resin backbone. Triethylamine was used for neutralisation and, hence, for further dispersion in water. Hydroxyl ethyl methacrylate was used for the synthesis to introduce unsaturation in the backbone of PUDs. The coating was made by an UV curing process. The coating was characterised for mechanical properties, chemical properties, thermal properties as well as stain resistance.

The polyurethane dispersion formed through it has ester and amide linkage present in it. The acetone process is used for its synthesis. The nuclear magnetic resonance spectroscopy confirms the successful formation of polyesteramide polyol and PUDs. Even though long aliphatic chains present in polyol which may impart hydrophobicity the synthesis PUDs well dispersed in water. It is observed as the coating made from it have hardness and scratch resistance properties. The coating also exhibits good stain resistance properties.

The method is an easy one to synthesise polyurethane dispersion from polyesteramide polyol, which is based on ester and amide linkage.

To the best of the authors’ knowledge, this is the first report on synthesised polyurethane dispersion from polyesteramide polyol. The polyesteramide resin already proves its excellence and upcoming technology in the coating industry. Here, they are incorporated into the synthesis of polyurethane dispersion.

This study aims to focus on how reactive diluents with mono- and di-functionalities affect the properties of resin formulation developed from bioderived precursors. A hydroxyethyl methacrylate (HEMA) terminated urethane acrylate oligomer was synthesized and characterized to study its application in stereolithography 3D printing with different ratios of isobornyl acrylate and hexanediol diacrylate.

Polyester polyol was synthesized from suberic acid and butanediol. Additionally, isophorone diisocyanate, polyester polyol and HEMA were used to create urethane acrylate oligomer. Fourier transform infrared spectroscopy and ¹H NMR were used to characterize the polyester polyol and oligomer. Various formulations were created by combining oligomer with reactive diluents in concentrations ranging from 0% to 30% by weight and curing with ultraviolet (UV) radiation. The cured coatings and 3D printed specimens were then evaluated for their properties.

The findings revealed an improvement in thermal stability, contact angle value, tensile strength and surface properties of the product which indicated its suitability for use as a 3D printing material.

This study discusses how oligomers that have been cured by UV radiation with mono- and difunctional reactive diluents give excellent coating characteristics and demonstrate suitability and stability for 3D printing applications.

The paper's aim is to synthesise ultraviolet (UV) curable polyurethane acrylate based on polyester polyol and to study change in its mechanical, chemical, optical and weather resistance properties with varying amount of nanosilica. It also seeks to determine its optimum loading levels for property maximisation.

New UV curable polyurethane acrylate has been synthesised using polyester polyol, blend of isophorone diisocyanate and toluene diisocyanate and hydroxyl ethyl acrylate. This resin was incorporated with nanosilica (1‐3 per cent) on the basis of total solids. The newly synthesised material was characterised by fourier transform infrared spectroscopy, gel permeation chromatography, X‐ray diffraction and scanning electron microscopy. The mechanical, chemical and optical properties of the coating films were studied and compared.

The hardness, tensile strength and abrasion resistance show significant enhancement with increasing amount of nanosilica. It is also found that UV cured polyurethane acrylate nanocoating exhibited improved weather resistance. The optimum concentration of nanosilica for better performance is found to be 3 per cent of total solids. The improvement is the result of inherent nature of nanosilica.

Nanosilica used in present context is having 10 nm mean diameter and near about 600 m²/g surface area. Nanosilica having different particle size, surface area and surface modification can be used to improve more specific properties.

Addition of nanosilica particles to polyurethane acrylate coating is a simple and inexpensive method resulting in phenomenal increase in properties.

The new organic‐inorganic hybrid nanocoating with improved weather resistance was synthesised. These coatings could find applications in demanding fields such as automotive topcoats.

The purpose of this paper is to develop a flexible, as well as a rigid, polyurethane (PU) product using polyols derived from renewable resource for suitable application.

Cardanol is converted into corresponding glycidyl ether by reacting it with epichlorohydrin. The resulting glycidyl ether is hydrolysed to the corresponding diol in the presence of a heteropolyacid, which acted as a catalyst. The diol obtained is used for synthesising PU's by reacting it with various mole ratios of toluene diisocyanate (TDI) and isophorone diisocyanate (IPDI) and their physicomechanical, chemical and morphological properties are studied.

The polyol selected for the present paper has unique structural characteristics such as C15 chain length, which contributes to flexibility, and an aromatic ring, which imparts rigidity in the final application of resulting PU. By choosing optimum ratio of NCO/OH, it is possible to obtain a system, which can be used for the development of a flexible as well as a rigid polymer for suitable application.

The cardanol and dodecatungstosilic acid used are of a particular grade and of a particular manufacturer. Furthermore, it could be obtained from different sources and of different grades. The spectral studies done are purely qualitative. Gloss is tested for the samples at 600, whereas other angles can also be used.

The method developed provided a simple and practical solution to improve performance characteristics of PU resins, which also proves to be cost effective.

The PU product developed due to its enhanced coating properties can be used in various surface‐coating applications.

The purpose of this paper is to synthesise environment friendly UV curable polyurethane acrylate resins for various industrial applications and study the performance properties of the cured coating films applied over metal surfaces.

The polyurethane acrylate resin was synthesised using polyester polyol (synthesised using ethylene glycol, adipic acid and 1,6 hexane diol), isophorone diisocynate (IPDI) and 2‐hydroxy ethyl methacrylate (HEMA). The different formulations were developed using various reactive diluents viz. monofunctional, difunctional, trifunctional and tetrafunctional (ethoxylated phenol monoacrylate, 1, 6 hexane diol di acrylate, dipropylene glycol di acrylate, trimethylol propane triacrylate, propoxylated trimethylol propane triacrylate, pentaerythrol triacrylate – PETA). These samples were cured under UV radiation. For effective curing, various compositions of oligomers, photoinitiator and reactive diluents were used. The mechanical, optical, rheological, chemical and stain resistance properties were evaluated.

The designed polyurethane acrylate gave good performance properties when used with reactive diluents having different functionality in different ratios for application over metal surfaces as protective coatings for various industrial applications. While using reactive diluents, the coating compositions showed significant enhancement of mechanical, physical and chemical resistance properties. Owing to different functionality of reactive diluents used, highly cross‐linked structures are formed, which lead to excellent mechanical and chemical properties. The optimum results were obtained with PETA as reactive diluent.

The polyurethane resin has been synthesised from polyester polyol (made up of ethylene glycol, adipic acid and 1, 6 hexane diol), IPDI, 2‐HEMA. Besides, this, it can be synthesised from some other polyester polyol or polyether polyol. In addition to this, some other isocyanates such as TDI, MDI, HDI, HMDI, etc. may be used.

The study has provided a better solution for developing low volatile organic compound (VOC) products by using UV radiations, which can be cured within a minimum period of time and can save significant application curing time for the end‐users. The developed product is also an environmentally friendly product.

Metallic surfaces are widely used in packaging industry in rigid and semi‐rigid forms. One of the prime requirements of the surface is an attractive printing on it. Conventionally used coating system on metallic surfaces are not holding or retaining their decorative effect/gloss level to a large extent. For this purpose, an overprint varnish is normally used which is mostly solvent based. This paper has been able to suggest very good formulations for printing of metallic surfaces for packaging and for overprinting in particular, which is radiation curable and environment friendly.

In this study, it is aimed to synthesize ultraviolet (UV)-curable water-borne polyurethane acrylate (WPUA) binders using different types of polyols (poly (propylene glycol), PPG₁₀₀₀ and PPG₂₀₀₀ and poly (ethylene glycol), PEG₁₀₀₀ and PEG₂₀₀₀) at different molecular weights, DMPA (2,2-bis(hydroxymethyl) propionic acid) at different amounts and isophorone diisocyanate (IPDI) and use for pigment printing on synthetic leather.

UV-cured films were characterized by Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimeter (DSC). The effect of binder structure on printing performance was determined with hardness, crock fastness, abrasion resistance and color measurements.

The highest abrasion resistance (60,000 cycles) and crock fastness values (dry crock and wet crock: 3/4) were obtained with binder PEG-C synthesized with PEG₂₀₀₀ and lower DMPA amount of 4.89 wt%; however, PEG-C binder showed lower hardness values. Due to lower urethane groups in PEG-C binder, more flexible films were obtained which imparted good adhesion property to printing film. Synthesized binders provided lower crock fastness and abrasion resistance properties than commercial WPUA binder.

Pigmented formulations including UV-curable water-borne synthesized PUA binder were developed and for the first time applied onto synthetic leather using screen printing method. Within this context, a new environmentally friendly printing method was proposed in this study including binder synthesis in the preparation of printing formulations.