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The purpose of this paper is to study interactions between water‐based polymer isocyanate (WPI) adhesive and bamboo by means of differential scanning calorimetry (DSC).

The method of adapting new reference substance replacing aluminium was used due to the special characteristic of WPI adhesive when studying reactions between WPI adhesive and bamboo.

The methods of changing reference substance could counteract effect of water in the sample on DSC measurement. The results of DSC analysis showed that hardener of WPI adhesive can react with water and also with ‐OH in bamboo and matrix of WPI adhesives. That is to say that a competition exists between urethane formation (covalent bonding of isocyanate with hydroxyl groups in bamboo and matrix in WPI adhesive) and urea formation (isocyanate consumption due to the reaction with water) during the operation of glued bamboo products.

The method of changing reference substance can be used for other DSC samples in which water cannot be conveniently removed, but this method requires that weight of reference substance to be exactly the same as the sample used in DSC measurement. So accuracy of weighing was very important in this DSC measurement.

The method developed in this paper provides a simple and practical solution to studying interactions between WPI adhesive and bamboo by means of DSC.

Changing reference substance was brought forward as a new method of counteracting effect of water in the sample on DSC measurement. The understanding gained through this study could help improve bonding properties of glued bamboo products.

The purpose of this study is to prepare a new self-emulsified waterborne epoxy hardener which can emulsify the liquid epoxy resin in aqueous media without addition of acid neutralizers.

Two synthetic steps were adopted to prepare novel self-emulsified amine-epoxy adduct type hardener composition based on the reaction of a commercially available polyetheramine, bisphenol A epoxy resin and triethylene tetramine. The different factors affecting the synthesis of the waterborne epoxy hardener were explored by emulsifying and curing properties. The process and products were analyzed and confirmed by FIRT.

Compared to an introduction of polyether as a hydrophilic segment in previous literature, whose reaction required Lewis acid catalysts and strict control of the presence of water, the introduction of polyetheramine to obtain a novel self-emulsified waterborne epoxy hardener were concise and convenient by mere two amine-epoxy addition steps in this research. Moreover, the final product offered good film formation with a practical value of mechanical properties, glass transition temperature and water-resistant property.

The self-emulsified waterborne epoxy hardener can be used to prepare water-resistant waterborne coatings from liquid epoxy resins while also providing the option of zero VOC formulations.

Introduction of hydrophilic polyether amine to prepare self-emulsified waterborne epoxy hardener without acid neutralizers has not been systematically studied previously.

THE object of this article is to deal with the present day use of urea‐formaldehyde resin glues in the aircraft industry. This type of glue is used in two spheres of the industry. (1) In the manufacture of plywood of aircraft quality, and (2) in the manufacture of wooden aircraft structures.

Coatings with outstanding chemical and physical properties can be obtained from two‐pack formulations without stoving. The epoxy resin was cured with different amine‐based compounds, such as polyamide (PA), the aniline copolymer of triethanolamine titanate and aniline formaldehyde. The thermal resistance properties of the cured films were analysed using the thermo‐gravimetric method. This study also examined the effect of coating resistance of 3 per cent sodium chloride solution by means of electrochemical impedance measurements. Coatings that included the epoxy triethanolamine titanate showed superior behaviour, compared to the other two systems tested. This hardener can be recommended instead of using conventional PA and polyamidoamide hardeners for epoxy two‐pack systems that are to be used to protect the steel structures from highly corrosive chemical and marine environments.

Future trends in surface coating developments must consider energy and raw materials prices, working cost, ecological imperatives and advances in technology. To be successful, a coating simultaneously must be non‐polluting, easy to apply in a short time and able to give good final properties. In the field of epoxy systems, these different aspect are well illustrated in the cases of thermosetting epoxy powder coatings and also with liquid epoxy acrylates which can be crosslinked by U. V. or β radiations, without heating.

Here, diazo coupling reaction was imparted on chemically inert lignin isolated from natural resources. Activated lignin was coupled with the diazotised aniline, m-nitroaniline, p-nitroaniline-, and p-anisidine gives organic pigments.

The continuous increase in particle size of pigments confirms addition of diazotised salt to lignin by coupling reaction. Further, the dispersing ability of these coloured pigments were exploited in polymer matrix. Epoxy-polyamine cross linking system was doped with difference percentage of pigments and coated on mild steel metal surface. The morphology of these composites was understood by SEM, particle size, differential scanning calorimeter and thermo gravimetric analysis.

The synthesised organic pigments were characterised by FT-IR, ¹H NMR and UV-visible spectroscopy. It was observed that hiding power of aniline- and m-nitroaniline–based azo pigments was more than p-nitroaniline- and p-anisidine–based azo pigments. Thermal properties as well as water contact angles of coatings were improved with pigment concentration. The chemical resistivity of coating was observed to be improved with the increasing % of lignin-based azo pigment.

Lignin-based azo pigment has great potential to replace metal oxide pigment and provide strategy for utilisation of lingo-cellulosic biowaste material.

Modern glues are manufactured with high moisture and water resistance; urea‐formaldehyde resins for gluing purposes are based on the fact that excellent control of the condensation reaction is possible by variation of pH, which can be applied easily at the production process. Among conclusions is that the shear stress of these resins is twice that of the unmodified type.

Epoxy curing agents are used to cure epoxy resins by reacting with the epoxide groups or by promoting self‐polymerisation of the epoxy by catalytic action. Application characteristics and final physical properties can be tailored by the choice of curing agent. The purpose of this study was to reduce the cost of epoxy hardeners (polyamide and Mannich base, which are commercially available) without affecting the properties of epoxy system and which are also useable as low temperature curing in flooring.

To prepare cost effecting Mannich base curatives for low temperature working environment without significantly affecting the properties such as toughening, adhesion, chemical resistance, etc. various compositions were made by incorporating liquid epoxy resin.

Mannich base curatives were prepared by using different amounts of phenol/bisphenol‐A, formaldehyde and polyamines to obtain products having different amine value, viscosity and colour. Liquid epoxy resin was cured by these Mannich base hardeners prepared. Drying time of relevant thin films was observed. These curatives showed excellent curing property at low temperature as well high humid conditions.

Mannich base curatives, used in present work was synthesised from phenol, DETA and dimethylamino propylamine. Besides, it could be synthesised from other phenol derivative such as cresol, resorcinol and cardanol. In the same manner, we can use other polyamines such as ethylenediamine.

The method provided a simple and practical solution to reducing the cost of Mannich base hardener without significantly affecting the desired properties.

The method used to prepare Mannich‐based hardener was cost affective and could find numerous applications in protective coatings.

To evaluate the performance of the blends of Mesua ferrea L. seed oil based polyurethane resins with a commercially available bisphenol‐A epoxy resin at different weight ratios.

For effective improvement of their various properties, polyurethane‐ester (PE) and polyurethane‐amide (PA) resins of Mesua ferrea L. seed oil were blended with a commercially available bisphenol‐A‐based epoxy (EP) in different ratios (PE or PA:EP = 100:40, 100:50 and 100:60 by weight) by using the solution blending technique in xylene. The tensile strength, impact strength, adhesive strength, flexibility, hardness, elongation at break, swelling behaviour and chemical resistance in different media of the films for both the blends have been studied.

The blending of PE and PA resins of Mesua ferrea L. seed oil with a commercially available bisphenol‐A‐based epoxy (EP) showed very good compatibility of the components as observed by SEM study. The blending also significantly improved the performance characteristics such as drying time, tensile strength, impact strength, adhesive strength, chemical resistance, etc. of the films.

The epoxy resin and the hardener are used of a particular grade of a particular manufacturer. Further, it could be obtained from different sources and of different grades. In addition, the performance characteristics could also be studied to optimise the exact blend ratio.

The method developed provided a simple and practical solution to improve the performance characteristic of polyurethane resin with less than one NCO/OH ratio.

The method for improving the performance characteristics of epoxy modified vegetable oil based polyurethane is something novel and could find numerous applications in surface coatings, adhesive and thin film.

A variety of thermoplastic and thermosetting polymers may be employed as binders in powder coating formulations. Some typical applications of various powder coatings are shown in Table 1.