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The purpose of this paper is to fabricate pre-existing geometries of the stents using solvent cast 3D printing (SC3P) and encapsulation of each stent with heparin drug by using aminolysis reaction.

The iron pentacarbonyl powder and poly-ɛ-caprolactone blend (PCIP) were used to print stent designs of Art18z, Palmaz-Schatz and Abbott Bvs1.1. The properties of antithrombosis, anticoagulation and blood compatibility were introduced in the stents by conjugation of heparin drug via the aminolysis process. The aminolysis process was confirmed by energy dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy due to presence of amide group and nitrogen peak in the respective analysis. Biological studies were performed to depict the cell viability, hemocompatibility and antithrombotic properties. Besides, mechanical behaviors were analyzed to study the behavior of the stents under radial compression load and bending load.

The amount of heparin immobilized on the Art18z, Palmaz-Schatz and Abbott Bvs1.1 stents were 255 ± 27, 222 ± 30 and 212 ± 13 µg, respectively. The cell viability studies using L929 fibroblast cells confirmed the cytocompatibility of the stents. The heparinized SC3P printed stents displayed excellent thrombo-resistance, anticoagulation properties and hemocompatibility as confirmed by blood coagulation analysis, platelet adhesion test and hemolysis analysis. Besides, mechanical behavior was found in context of the real-life stents. All these assessments confirmed that the developed stents have the potential to be used in the real environment of coronary arteries.

Various customized shaped biodegradable stents were fabricated using 3D printing technique and encapsulated with heparin drug using aminolysis process.

The purpose of this paper is to discuss the synthesis of polyesteramide resin from the monomer obtained from poly (ethylene terephthalate) (PET) waste and study of the structure – property relation for the same in polyesteramide coating. The purpose is also not only to just target the polymeric waste but also to study the effect of the structure of monomer obtained from such waste in final coating.

PET waste was depolymerised using diethanolamine to tetra(2,2-hydroxyethylene) terephthalamide (THETA). Four functional hydroxyl terminated monomers were generated having amide linkage as a structural part. THETA was used for the synthesis of polyesteramide resin along with fatty amide of oil, and concentration of the THETA was varied. The synthesised polyesteramide resin was cured with MF resin and tested for physico-chemical, thermal and anticorrosive properties.

PET was successfully depolymerised to monomeric level using diethanolamine as a reactive agent. It is observed that as the concentration of THETA increases, the hardness of the coating increases, as aromatic concentration increases in the coating. The amide linkage helps to improve adhesion as well as hydrophobicity because an aliphatic long chain of fatty amide and aromatic linkage of THETA helps in improving anticorrosive properties of the coating.

This method is the useful key to solve the polymeric waste problem. PET can be easily depolymerised using diethanolamine and polyesteramide resin synthesised from it. Hence, waste material can be converted into the coating by reacting it with renewable resources.

To the best of the authors’ knowledge, this is the first study which uses THETA as a monomer for the synthesis of polyesteramide resin and study of its various concentrations on coating properties. The coating is obtained from waste material; hence, polymeric waste issue is also solved, and dependency on the petroleum resources to obtain raw materials for coating is also depleted partially. The study also helps to understand the effect of the structure of monomers on the properties of the coating.

The purpose of this paper is synthesis of polyesteramide resin from jatropha oil and monomer from recycling of poly(ethylene terephthalate) (PET) to get the excellent benefit of individual structure. Along with the synthesis of polyesteramide resin, this research work will also help in recycling of PET waste and help for the conversion of monomer obtained from recycling of PET to value-added application.

Polyesteramide resin was synthesized by conventional method, i.e. by converting jatropha oil to corresponding fatty amide, i.e. hydroxyl ethyl jatropha oil fatty acid amide (HEJA), and treating it with dicarboxylic acid, i.e. sebacic acid but bis(2-hydroxyethyl) terepthalamide (BHETA) is added, i.e. monomer of PET, and then resin synthesis is carried out. Synthesized resin is cured with isocyanate and used for coating application. Coating is characterized for physical, mechanical, thermal and anticorrosive properties.

Coating shows excellent balance of flexibility and hardness due to structural difference in BHETA and HEJA. Aromatic structure of BHETA was helpful for increasing hardness and for retardation of degradation, and at the same time, aliphatic structure of HEJA was helpful for increasing flexibility of the coating. Amide linkage present in both help for better adhesion of coating to metal surface, which also helps to improve the mechanical properties and anticorrosive properties.

This method is the practical solution for synthesis of polyesteramide resin and then coating from PET waste and jatropha oil. Hence the method developed is simple and it helps for recycling of PET waste and conversion of recycled product to value-added material.

To the best of the authors’ knowledge, this is the first study which use jatropha oil (fatty amide of jatropha oil) and PET waste (monomer of PET waste) simultaneously for the synthesis of polyesteramide resin and then coating.

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.

The majority of binders used in paint manufacture are either highly‐viscous or solid materials in their own right. The identification of their chemical constituents has been reported by Haken (71) using infrared spectroscopy at liquid nitrogen temperature. However, the procedure proved to be very expensive since a great deal of breakage of the equipment occurred owing to the need to keep cooling and then reheating to room temperature. A better procedure was considered to be fragmentation of the initial polymer samples to give volatile fractions better suited to GC examination, which was just as accurate as the spectroscopic approach and far simpler and cheaper to carry out.

This study aims to enhance the dyeability of polyester fabrics with turmeric natural dyes through plasma and alkaline treatments. The aim is to achieve better color strength in dyed samples without significant changes in their other properties. This is done while the weight loss is kept in a range with no considerable effect on those properties.

The surface of a poly(ethylene terephthalate) fabric was modified using oxygen plasma at a low temperature. The alkaline hydrolysis of that polyester fabric was also done through treating it with an aqueous sodium hydroxide (NaOH) solution. The untreated and treated polyester fabrics were studied for the changes of their physical characteristics such as weight loss, wetting behavior, strength loss, bending length, flexural rigidity and K/S and wash fastness. The samples were treated with plasma and sodium hydroxide and dyed with a turmeric natural dye.

In comparison to the untreated sample, the plasma-treated, alkaline-treated and plasma treatment followed by alkaline hydrolysis polyester experienced 9.3%, 68.6% and 102.3% increase in its color depth as it was dyed with a turmeric natural dye, respectively. The plasma treatment was followed by alkaline hydrolysis. The improvement in the color depth could be attributed to the surface modification.

In this paper, investigations were conducted of the separate effects of plasma treatment and alkaline hydrolysis as well as their synergistic effect on the dyeing of the polyester fabric with a natural dye obtained from turmeric.

The purpose of this study is to check the effectivity of plasma in the natural dyeing of polyester fabric using four natural dyes – Turkey red, Lac, Turmeric and Catechu using plasma and alum mordant. The surface modification on the polyester fabric by plasma along with the use of benign mordant alum is studied. The enhancement of dyeability in polyester fabric with natural dyes is the main focus. Due to surface modification, the wettability increases, which leads to better dye uptake. Better dye uptake and better dye adherence are the main objectives.

Plasma-mediated natural dyeing is the main design of this research work. The effect of plasma treatment on surface modification of synthetic fabric polyester and its subsequent effects on their dyeing with different natural dyes, namely, Turkey red, Lac, Turmeric and Catechu are studied. The dyeability was further enhanced by the use of alum as mordant. The main focus is on the betterment of natural dyeing of polyester fabric using sustainable natural dyes resources for dyeing and to reduce wastewater contamination from the usage of toxic additive chemicals for cleaner production.

Plasma-mediated and alum-mordanted dyeing method facilitated very good dyeability of all the four natural dyes, namely, Turkey red, Lac, Turmeric and Catechu. Color strength (K/S) values and fastness properties of plasma-treated samples were far better than untreated samples. The synergistic effect of plasma and alum mordanting has made natural dyeing of polyester very easy with very good fastness results. Natural dyeing of polyester after 2 min of plasma treatment showed excellent and desirable results. The process is also easy to be adapted by industries.

As polyester is hydrophobic, natural dyeing of polyester fabric is not very easy, but with plasma-mediated natural dyeing, it becomes a very facile dyeing method; thus, there are no limitations. Use of plasma has reduced the need for any chemical additives which are usually added during the dyeing process.

This process of natural dyeing of polyester fabric can be scaled up to industrial dyeing with natural dyes. Plasma pretreatment of the fabric followed by premordanting with alum has facilitated the natural dyeing well.

Use of plasma in place of chemical modifiers can be a green and environmentally friendly approach for sustainable coloration of polyester fabric, providing a clean wet processing for textiles dyeing.

The synergistic effect of plasma-mediated and alum-mordanted natural dyeing of polyester has not been attempted by any researcher. To the best of the authors’ knowledge, this is for the first time that pretreatment with atmospheric plasma followed by alum mordanting of polyester fabric has shown very good dye uptake and fastness properties as the dye molecules could penetrate well after 2 min of the plasma treatment.

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.

Most of the “alkylolamides” are derived from ethanola‐mines and fatty acids like stearic, lauric, myristic and oleic. The general method of preparation of these compounds involves the use of low molecular weight aminohydroxy compounds and acylation of amino group with higher fatty acids. Amino group may be primary or secondary. Also, hydroxyl group may be more than one.

Preparation of chelating resin to be used in the removal of heavy metal ions from solutions.

Chelating resin based on poly (glycidyl‐methacrylate‐co‐N, N‐methylene‐bis‐acrylamide) containing ethylenediamine was synthesised and used in removal of heavy metals from solutions.

The optimal pH values for adsorption of different metal ions occur in the range 4.0‐10.0 depending on the metal ion used. The adsorption of metal ions increases with increasing treatment duration to reach to the equilibrium state. Also, the adsorption of metal ions depends on the degree of cross linking of the chelating resin, and a higher degree of cross linking results in a lower degree of metal ion adsorption. The chelating resin was highly effective for the collection of metal ions by batch and column methods. The metal ions adsorbed could be eluted with 2M HNO₃ except Co²⁺ and the resin could be reused.

The different factors affecting the metal ions (Cu²⁺, Co²⁺, Cd²⁺, Zn²⁺, Pb²⁺ and Hg²⁺) loading in resin such as pH, contact time and cross linking density were studied.

The practical applicability of the chelating resin for final stage of waste water treatment is recommended for use as a polishing agent.

The resins prepared were used successfully in removing heavy metals from water.