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The purpose of this paper is to get the insulating polyurethane (PU) as conductive type polymer by compositing with oligoanilines, namely, tetraaniline (TANi) with an implication of its use as anti-corrosion coating material.

Water dispersion of PU was prepared and used as a host material for TANi for composite formulation.

The composites are very useful as anti-corrosion coating on mild steel as evident from Tafel polarisation studies.

The solubility of TANi is limited in other organic solvents; because of this, a high-boiling solvent like N-methyl-2-pyrrolidone (NMP) is used.

It can be used as a good anti-corrosion coating on mild steel. Apart from anti-corrosion material, this can be used as conductive-based sensor material and also electrostatic dissipation (ESD) or electromagnetic interference (EMI) shield.

The work is original.

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.

Waterborne polyurethane dispersions (PUDs) continue to show growth in commercial usage due to the ever increasing environmental legislation to reduce VOC in coating and adhesive materials. The transition from solvent‐based to waterborne has also been facilitated by advances in both the chemistry and technology employed and the formulation expertise required. This has resulted in coating performance that cannot only match but in some cases surpass their solvent‐based counterparts. This paper gives an overview of PUDs and introduces urethane/acrylic hybrids, giving an insight into the chemistry and technology. Particular emphasis is given to new developments and the application areas where they are finding increasing use. Some formulating techniques are also illustrated.

The purpose of this paper is to synthesise polyurethane/polyacrylate (PU/AC) core‐shell hybrid latex by emulsion polymerisation (PUA) and interpenetrating hybrid latex by soap‐free emulsion polymerisation techniques latex interpenetrating polymer networks (LIPN) and to compare their physico‐chemical and thermo‐mechanical properties.

The interactions between the PU and AC components in hybrid coatings were studied with infrared spectroscopy. Mechanical properties were determined by measuring Shore A hardness, pencil hardness and flexibility of dried films. A particle size analyser and scanning electron microscopy were used to investigate the morphology of hybrid resins. Differential scanning calorimetry and thermogravimetric analysis were performed to investigate the thermal stability of polymeric films.

The core‐shell hybrids had better physico‐chemical and thermo‐mechanical properties than LIPN hybrids, attributing better interpenetration and entanglement between PU/AC in emulsion polymerisation.

The syntheses of hybrid polymers can be extended for various combinations of acrylate monomers with crosslinkers, as well as for different types of PU ionomers.

The comparative study provides a simple and practical solution to improve performance characteristics of PU/AC hybrid coatings, which also proves to be cost effective.

The findings are of interest to those in surface coatings and adhesive applications.

Discusses the manufacture of polyurethane dispersions. States that excellent properties (including good early green strength, high ultimate bond strength, good open time, good adhesion to a variety of substrates, high heat resistance, low heat activation temperature, ability to be blended with other water based polymers and additives) can be obtained with lower environmental impact than for solvent‐based adhesives. Discusses how price/performance can be improved through the addition of less expensive resins. Outlines major applications for polyurethane dispersions in automotive, furniture and footwear industries.

The purpose of this paper is to synthesize and characterize a series of two-component aromatic waterborne polyurethane (2K-WPU) which is composed of non-ionic and anionic polyisocyanate aqueous dispersion and polyurethane polyol aqueous dispersion.

The polyisocyanate aqueous dispersion was synthesized through non-ionic and anionic hydrophilic modification procedures. The values of the hydrogen bonding index (HBI) and molecule structures of WPU were obtained by Fourier transform infrared (FTIR). The thermal, mechanical and water resistance properties of 2K-WPU films were investigated.

The appearance of non-ionic polyisocyanate aqueous dispersion and anionic polyisocyanate aqueous dispersion was colorless translucent pan blue and yellow opaque emulsions, respectively. FTIR not only showed that 2K-WPU was obtained from the polymerization of polyisocyanate component and polyhydroxy component by polymerization but also showed that the content of hydrogen bondings of anionic 2K-WPU (WPU 2) was higher than non-ionic 2K-WPU (WPU 1). The glass-transition temperature (Tg), storage modulus and water resistance of WPU 2 were higher than WPU1, whereas the thermal stability of WPU1 was better than WPU 2.

The investigation established a method to prepare a series of 2K-WPU which was composed of non-ionic or anionic polyisocyanate aqueous dispersion and polyurethane polyol aqueous dispersion. The prepared 2K-WPU film could be applied as substrate resin material in the field of waterborne coating.

The paper established a method to synthesize a series of 2K-WPU. The effect of HBI value and the molecule structure of soft segment on the thermal stability, mechanical and water resistance properties of 2K-WPU films were studied.

Modified styrene/butadiene (S/B) latexes from Dow Europe have been shown to give added performance in primer/sealers by offering excellent moisture vapour barrier, hydrolytic stability and high binder efficiency.