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Linseed oil was employed to modify polyesteramide resin via the condensation of hydroxyethylamide derivatives of fatty acids of linseed oil, i.e. {N, N′‐bis(2 hydroxylethyl) linseed amide} and phthalic anhydride and dicarboxylic acids such as adipic acid, succinic acid and sebacic acid. The polyesteramide resins obtained were tested for their application as a vehicle/binder in the preparation of surface coatings. The resins obtained were also characterised for their physico‐chemical properties, film forming properties and chemical resistance.

The binder or media component of surface coatings can be subdivided into two broad groups, non‐convertible and convertible, which differ in their mode of film formation. Binders of the non‐convertible type do not undergo chemical conversion reactions whenthey cure, and film formation here involves loss or evaporation of a volatile solvent and concomitant deposition of the solid binder. Important members of this group are the rubber derivatives and the many examples of vinyl copolymers; some recent developments in the technology of these polymers were described in the previous article in this series. This article will consider the convertible media used in coatings, where film formation involves some form of chemical reaction. Commencement of this reaction is dependent upon either the presence of a suitable initiator, or by exposure to some form of radiant energy, which causes the binder (in the form of a monomer or partially‐polymerised component) to rapidly polymerise. This polymerisation reaction can take one of several forms though the result is the same; the binder and hence the liquid paint is converted into a solid material which is substantially insoluble in the original carrier solvent. This review will consider some of the recent literature concerned with three important members of the convertible group of media; alkyd, epoxy and polyurethane resins.

The purpose of this investigation was to develop sustainable resource-based anticorrosive coating material using Pongamia glabra seed oil and tannic acid (TA), as well as to improve the coating properties.

TA-modified fatty amide diol was synthesized by condensation polymerization. First, Pongamia glabra seed oil was converted to fatty amide diol (Pongamia oil fatty amide, PFA) that was further modified by TA with different parts per hundred of resin (10, 15 and 20) to develop a polyether fatty amide (PFA-TA). The confirmation of reaction between TA and PFA was carried out using Fourier transform infrared spectroscopy. The thermal behavior of PFA-TA was studied by thermogravimetric analyses. Coatings of several PFA-TA resins were applied to steel (i.e. plain carbon steel) coupons to investigate their physico-mechanical and anticorrosive performance. The corrosion protection performance was observed using AC impedance and polarization tests.

TA-modified fatty amide coatings showed the highest scratch hardness of 2.5 kg, flexibility (1/8 inch) and gloss at 45° was 60-62. Among all compositions, PFA-TA15 showed the best physico-mechanical and anticorrosion performance. Corrosion tests of coated panels were examined in different corrosive media (3.5 wt per cent HCl, 3.5 wt per cent NaOH and 5.0 wt per cent NaCl) using potentiodynamic polarization and AC impedance measurements. PFA-TA may find application as an eco-friendly protective coating, and thermal analyses revealed that it can be safely used up to 300°C.

This paper provides the development of protective coatings for steel from non-edible seed oil and TA to utilize sustainable resources.

The primary purpose of this work is to prepare the renewable source-based polyurethanes coatings which can be used to substitute petroleum-based materials. In the secondary purpose, the paper included improvement in the properties of said PU coatings using modified nano TiO₂ for industrial PU coatings.

The authors have synthesised low molecular weight polyols (monoglycerides) based on vegetable oils such as castor, linseed, coconut, mustard, sunflower and rice bran oils. These monoglycerides were successfully utilised in the preparation of polyurethane coatings. In order to improve the performance of these coatings, modified nano TiO₂ was incorporated into them. The particle size of TiO₂ was determined by transmission electron microscopy. Coatings prepared were characterised for their properties such as gloss, scratch resistance, impact resistance, flexibility, cross cut adhesion and chemical resistance. The thermal stability of coatings was also studied by thermo gravimetric analyzer.

The polyurethane coatings prepared from six monoglycerides of different oils with polymeric diphenyl methane diisocyanate showed good chemical resistance and thermal stability. Coating properties like impact resistance, flexibility and adhesion were excellent for all of the prepared samples of PU coatings. PU coatings with excellent hardness up to 5B were found with the modification of nano TiO₂ by silane coupling agent. The authors successfully prepared the renewable source-based (monoglycerides of oil) PU coatings.

Practically the authors are able to convert renewable source that is vegetable oils into polyurethane coatings which may have strong potential to be used as industrial surface coating. The properties of the PU coatings were evaluated before and after the incorporation of different concentration of surface-modified nano TiO₂ which revealed that the presence of 1 percent nano TiO₂ showed significant enhancement in coating properties.

The beauty of this work includes synthesis of polyurethanes coatings from renewable source material (monoglycerides of vegetable oils) to substitute petroleum-based materials. The incorporation of silane-modified TiO₂ nanoparticles in renewable source-based PU coatings is another originality of the work. This article is also representing comparative study of various vegetable oils on PU coatings.

Polymeric systems based on polyesteramides (PEA) are high performance materials, which combine the useful properties of polyester and polyamide resins, and find many applications, most importantly as protective surface coatings. The purpose of this paper is to characterise and evaluate new modified anti‐corrosive PEA resins for use in protective coating formulations.

In the study report here, new modified PEA compositions were prepared and evaluated as vehicles for surface coating. The PEA resins were obtained by means of a condensation polymerisation reaction between phthalic anhydride (PA) and N,N‐bis‐(2‐hydroxyethyl) linseed oil fatty acid amide (HELA) as the ingredient source of the polyol used. The phthalic anhydride was partially replaced with N‐phthaloylglutamic acid NPGA as the ingredient source of the dibasic acid. The structure of the resin was confirmed by FT‐IR spectral studies. Coatings of 50±5 μm thickness were applied to the surface of glass panels and mild steel strips by means of a brush. The coating performance of the resins was evaluated using international standard test methods and involved the measurement of phyisco‐mechanical properties and chemical resistance.

The tests carried out revealed that the modified PEA based on N‐phthaloylglutamic acid (NPGA) enhanced both phyisco‐mechanical and chemical properties. Also, the resins were incorporated within primer formulations and evaluated as anti‐corrosive single coatings. The results illustrate that the introduction of N‐phthaloylglutamic acid, within the resin structure, improved the film performance and enhances the corrosion resistance performance of PEA resins.

The modified PEA compounds can be used as binder in paint formulations to improve chemical, physical and corrosion resistance properties.

Modified PEA resins are cheaper and can be used to replace other more expensive binders. These modified PEA resins can compensate successfully for the presence of many the anticorrosive paint formulations and thus lower the costs. The main advantage of these binders is that they combine the properties of both polyester and polyamide resins based on nitrogenous compound, are of lower cost, and they also overcome the disadvantages of both its counterparts. Also, they can be applied in other industrial applications.

Medical tourism demands tremendous responsiveness and accountability. The triple bottom line in medical tourism indicates that these organizations must emphasize on economic profits, environmental protection, and conservation of social resources. Developing a resilient medical tourism ecosystem is another critical necessity after the COVID-19 pandemic. The present study attempts to study the various aspects of medical tourism while synthesizing the relevant theories. This synthesis was used to propose a framework for developing a resilient medical tourism system. The outcomes of the chapter also propose the long, medium, and short-term goals. These goals focus on relevant stakeholders for developing highly integrated and resilient medical-tourism destinations.

Companies are constantly striving for superior customer service that meets consumers' expectations. Products that do not provide consumers with good service quality are unlikely to meet the expectations of consumers. The aim is to maximize customer satisfaction and achieve financial success by closing gaps to provide high-quality service to consumers. Customers use quality of service to choose a service provider. This does not only include the quality of products or service but also the quality of customer service. The five essential elements (5Es) – experience, emotions, exclusivity, execution and engagement – must be used by companies to ensure that their products and services meet defined standards or customer's expectations. The customer's opinion of a service is formed immediately, regardless of whether it is positive or negative. The result of a negative customer experience is negative word of mouth, which would cause loss in business from dissatisfied customers as well as from potential customers who will no longer use the services. Using the gap model for service quality, this study proposes the essential 5Es of service quality. As a result of the synthesis of this current research, the company's service delivery will be improved by identifying weaknesses. The use of these 5Es for the control of service quality and monitoring of quality defects leads to better understanding and reduction of cost.

Attempt has been made in this study, to utilize castor oil in the preparation of polyesteramide resins. Castor oil was first converted into dehydrated castor oils (DCO) to improve drying characteristics. DCO was then converted into diethanolamide {(N, N‐ bis hydroxethyl) castor oil amide} of mixed fatty acids using 0.5 per cent sodium methoxide as a catalyst and converted to polyesteramide resins after reacting with various dibasic acids such as phthalic anhydride, sebacic, succinic and adipic acids in presence of xylene as azeotropic solvent. The resins obtained were then analysed for its physico‐chemical, film performance properties and resistance to various chemicals.

Polyesteramide resin based on the condensation of hydroxyethylamide derivatives of fatty acids of soybean {N, N′‐bis(2 hydroxyethyl)soybean amide} and various dibasic acid and anhydride were synthesized. Physico‐chemical characteristics and film forming properties of these resins were determined to prove its suitability as a vehicle for surface coatings. The study reveals that resins can be used for the baked type of finishes.

The purpose of this paper is to propose a novel method to prepare pure Ti powder for 3D printing with tailorable particle size distribution.

The main procedures of the present method consist of gas state reaction to synthesize TiH₂ nanoparticles, agglomeration to obtain micronscale powder particles by spray drying, and densification of particle interior by heat treatment.

The prepared Ti powder has a specific bimodal particle size distribution in a range of small sizes, good sphericity and high flowability. Particularly, this new technique is capable of controlling powder purity and adjusting particle size.

To the best knowledge of the authors, the approach for preparing 3D printing metallic powders from nanoparticles has not been reported in the literature so far. This work provides a novel method that is particularly applicable to prepare 3D printing metallic powders which have small initial particle sizes and high reactivity in the air.