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UV curing processes of materials have to be specially designed accordingly in order to obtain the optimized property for different electronics applications. The purpose of this study is to characterize and study the curing and thermal behavior of a two‐component epoxy‐based UV curable coating in electronics assembly with various thermal analysis techniques. Curing behavioral change in terms of UV light, UV exposure time, wavelength, modulus, thermal stability, organic volatile outgassing and volume was discussed. Process optimization of coating materials that were UV cured at 30°, 100° and 150°C for 1 and 10 min was further investigated. Moreover, the relationship between photocuring conditions and the resultant surface hardness was studied and correlated from the results of dynamic microhardness measurements. Thermal and hardness properties of the above processed coating materials before and after isopropyl alcohol saturation were also investigated.

Epoxy acrylate which is commercially utilized for UV curable coatings although has excellent adhesion, flexibility, hardness and chemical resistance, they lack in antimicrobial properties. Citric acid (CA) is economical as well as a bio-based compound which possess an antimicrobial activity. So, the purpose of this research investigation is the preparation of CA-based oligomer which can be further incorporated with epoxy acrylate and tri (propylene glycol) Diacrylate (TPGDA) to form uv curable coating and the study of its antimicrobial property.

A UV-curable unsaturated oligomer (CUV) was synthesized from CA and glycidyl methacrylate (GMA). The chemical structure of CUV was confirmed by FTIR, ¹H NMR, GPC, hydroxyl value, acid value and iodine value. Further, CUV was assimilated as an antimicrobial as well as crosslinking agent to copolymerize with epoxy acrylate oligomer and a series of UV-cured antimicrobial coatings were concocted by employing UV-curing machine. The consequence of varying the fraction of CUV on the mechanical, chemical, thermal and antimicrobial properties of UV-cured wood coatings was explored.

Results exhibited good mechanical, chemical and thermal properties. In addition, it was perceived that the zone of inhibition against S. aureus got enlarged with increasing content of CUV in the coating formulation.

The synthesized bio-based CUV reveals an extensive potential to ameliorate the antimicrobial properties of UV-curable coatings.

For the sake of sustainable development and environmental preservation, it is crucial to develop UV-curable coatings composed of renewable resources. Castor oil, being both bio-based and economical, serves as the focal point of this research paper. The purpose of this research paper is to synthesize, formulate and apply a UV-curable biobased oligomer ECOSAGMA as a wood coating, with a focus on sustainable development and environmental preservation. Castor oil, being both bio-based and economical, serves as the focal point of this research paper.

ECOSAGMA was prepared by reacting epoxidized castor oil with sebacic acid, followed by reaction with glycidyl methacrylate through ring opening reaction. The chemical structure of ECOSAGMA was confirmed by Fourier-Transform infrared spectroscopy, 13C-NMR and 1H-NMR spectroscopy. The synthesized oligomer was used for UV-curable coating formulations by combining it with varying amounts of TMPTA from 10 to 40 wt.% and studied for their rheological properties. The UV curable formulations were co-photopolymerized into thin coatings and were thoroughly examined based on thermal, chemical and mechanical properties.

The UV-cured coating containing ECOSAGMA and TMPTA exhibits exceptional mechanical, chemical and thermal properties, underscoring their potential for deployment in real-world application. It is observed that an increase in the concentration of TMPTA is associated with a notable enhancement in the properties of the UV-cured coatings. The UV-cured wood coating, composed of 40 wt.% TMPTA, demonstrates remarkable stain resistance properties.

In conclusion, by embracing eco-friendly and economically conscious principles., it is evident that this synthesized novel castor oil-based oligomer offers a range of valuable properties to the coating such as stain resistance and thermal stability as well as characteristics such as gloss, hardness, adhesion and chemical resistance.

The purpose of this work was to develop a new trispiperazido phosphate-based reactive diluent (diphosphate-piperazine hydroxyl acrylate [DPHA]) and used as a flame retardant with an epoxy acrylate (EA) in ultraviolet (UV)-curable wood coating.

The concentration of reactive diluent was varied from 0% to 20% in the UV-curable formulation with constant photoinitiator concentration. The effect of DPHA concentration on film properties was studied by differential scanning calorimetry and thermogravimetric analysis, gel content, water absorption and limiting oxygen index.

The results showed that the viscosity of the prepared formulation decreased by increasing reactive diluent (DPHA) concentration which leads to improving the coating efficiency. A high concentration of reactive diluent (DPHA) of the cured films shows good resistance against stain, mechanical and thermal properties, which results in an increased glass transition temperature (T_g) and cross-linking density of the films.

The new trispiperazido phosphate-based reactive diluent was used in wood coating formulation, which resulted in excellent flame-retardant properties with higher cross-linked density with good stain resistance. This material can provide a wide range of application for coating industries to produce a glossy finish.

The purpose of this paper is to develop palm oil‐based alkyds as ultraviolet (UV) curable coatings and investigate the parameters that affect the coating performances.

Alkyds were formulated from palm stearin, glycerol, phthalic anhydride and maleic acid. Keeping the total molar amount of dicarboxylic acids constant, the proportions of maleic acid and phthalic anhydride were varied in order to produce polymer chains with different content of unsaturation, which is crucial for UV curability. Characterisations were carried out by FTIR and 1HNMR. The alkyds were then mixed with methyl methacrylate (MMA) monomer as active diluents and cured by exposure to UV light. Performances of the cured coatings were tested in terms of film hardness, adhesion, water and alkali resistance, and thermal stability.

Upon introducing sufficient C=C, the alkyd in combination with MMA is able to UV‐cure within short time and produce film of satisfactory quality. There are several other factors, which influence the coating properties; these include thickness of coating, ratio of alkyd to active diluents, and duration of UV exposure.

The product is a form of green technology that could benefit the environment as it involves very low or near zero emission of volatile organic compounds (VOC).

The novelty of this work lies in the formulation of new products from palm stearin, leading to new developments in the surface coating and palm oil industries.

The purpose of this paper is to invent a new functional coated fabric based on nanomaterials to shield UV and IR. Multifunctional surface coatings with ultraviolet (UV)/near infrared radiations protection and waterproof were widely applied in outdoor fabrics. Herein, ultrafine TiO2 and nano-antimony doped tin dioxide (ATO) were prepared and embedded into water-based polyurethane (PU) coatings and then coated on the nylon fabric.

ATO was prepared using the sol–gel method and the two powders were dispersed by ball milling. The results of zeta potential and particle size distribution showed that the ultrafine TiO2 and nano-ATO could be stably dispersed in water at pH 8 with the presence of sodium polycarboxylate. The optimal process was screened out by orthogonal design and scanning electron microscopy (SEM), UV protection, thermal insulation and water-pressure resistance were tested. SEM images indicated the nanoparticles could be uniformly dispersed in the coatings.

The effect of UV prevention can get to UPF > 50, UVA < 5 per cent, which meet up with the AATCC 183-2014. Coatings can effectively lower the temperature of fabric surface by 8∼9ºC through the self-made closed test system and by 3ºC through the open test system.

These PU coatings are environment-friendly and adhesive to impart waterproof, UV-proof and thermal insulation properties to nylon fabrics by coating finishing.

The paper aims to design the optimum formulation of the nano-titanium dioxide (TiO2) hydrophilic coating system using the synthetic polypropylene glycol (PPG), which can create the reflection and absorption property.

TiO2 nanoparticles are used as fillers, and PPG has been blended at the proper ratio of 1PPG: 0.2TiO2. The prepared resin has been applied onto the glass substrate at different numbers of glass immersions during the dip-coating fabrication process. One-time glass immersion is labeled as T1 coating, two-time glass immersion is labeled as T2 coating and three-time glass immersion is labeled as T3 coating. All the prepared coating systems were left dry at ambient temperature.

T3 coating showed the lowest reading of WCA value at 40.50°, due to higher surface energy at 61.73 mN/m. The T3 coating also shows the greatest absorbance property among the prepared coating systems among the prepared coating. In terms of reflectance property, the T2 coating system has great reflectance in UV region and near-infrared region, which is 16.47% and 2.77 and 2.73%, respectively. The T2 coating also has great optical transmission about 75.00% at the visible region.

The development of thermal insulation coating by studying the relationship between convection heat and reflectance at different wavelengths of incident light.

The developed coating shows high potential for glass window application.

The application of the hydrophilic coating on light absorption, reflectance and transmission at different wavelengths.

This paper aims to focus on a comparison study of the visible stability of natural blue dye consisting anthocyanin molecules extracted from Clitoria ternatea in coating films.

The coating films were prepared by mixing the blue dye with poly(acrylamide-co-acrylic acid) in three different weight ratios. Samples were coded as 10PBA, 15PBA and 20PBA, where PBA is the abbreviation for poly acrylamide-co-acrylic acid, blue dyes and anthocyanin. The number at the beginning of each code represents the weight percentage of poly(acrylamide-co-acrylic acid) to natural blue dye. The mixtures were applied on separate glass substrates to form coating films. Another set of samples were prepared for the comparison study with a commercial acrylic clear coat (cc) applied on the surface of the 10PBA, 15PBA and 20PBA coating films. These coating films were coded 10PBAcc, 15PBAcc and 20PBAcc. The purpose of the clear coat is to observe how it affects the colour stability of the blue coating films with respect to time. All samples were exposed to the ultraviolet (UV) source, an 18 W Philips TL-D 18w/830 UV fluorescent lamp. The UV lamp was placed 15 cm above the surface of the samples for 35 days. The colour of the coatings was measured using CIE L*a*b* colour space coordinate.

The results obtained show 10PBA and 10PBAcc have the highest colour stability after 35 days of exposure to UV light. The reflectivity of the coating films was also measured during exposure to UV lamp. Reflectivity measurements also showed that 10PBA and 10PBAcc coating films had the highest reflective stabilities.

The potential of using natural blue dye consisting anthocyanin in coating film to obtain high colour stability.

The coating film developed in this work is suitable to be applied on glass substrates.

The application of anthocyanin dye extracted from the Clitoria ternatea L. as a colourant in coating films

UV curable systems have found wide applications in clear coatings. However, coatings containing pigment showed a degree of curing inhibition due to the absorption, scattering and reflection of the UV radiation caused by the presence of pigments in the coating film. This results in poor through‐cure and consequently in poor adhesion. Thus, pigments used in the UV curable coating systems should not absorb radiation in the same region as the photo‐initiators. One of the solutions to such a problem, reported in this paper, was to develop more reactive, alcohol soluble, non‐heat reactive, low molecular weight cresol based, pigmented novolac epoxy acrylate systems, which have a lower absorption in the UV region. In addition, the effects of several photoinitiators having absorption in the longer wavelength region of the UV spectrum were investigated.

Describes the use of a new type of UV cured coating and adhesive which are not adversely affected by fluorescing agents, so that increased quantities of fluorescing agents can be employed without retarding the depth of cure. Therefore, UV cured coatings and adhesives with this enhanced fluorescent response can readily be observed by the human eye using “black light” or by an on‐line electro‐optical device for quality control analysis of each electronic assembly.