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The problems associated with preserving the steel sheeting of water‐sealed gasholders have been known for some time. Various techniques have been adopted, e.g. protective painting, oil filming and sacrificial anodes. This paper deals with painting, and the two groups of paints used in the experiments were chosen for (1) their blister‐suppressing qualities and (2) their good adhesion and water resistance.

Polystyrene glycol was prepared and incorporated into linseed alkyd. Compatibility of polystyrene glycol and alkyd was investigated. It was found that 20 per cent polystyrene glycol could successfully be blended with linseed alkyd. Film properties of these blends were examined and compared with those of plain alkyd. It was observed that polystyrene glycol modified linseed alkyds were superior, in film properties, to the plain alkyd except in solvent resistant property.

Yellowing of vegetable oils in coatings continue to be a problem to paint formulators and users and to resin manufacturers. This characteristic occurs in coatings where there is unsaturation in the triglyceride fatty acid residues of the oils used in the resin or binder. Yellowing is the single most important factor which limits the use of linseed oil‐based white paints and enamels for external use in buildings. A thorough understanding of this phenomenon is necessary to the resin manufacturer and paint formulator. Unfortunately, yellowing of vegetable oils in coatings is still a controversial subject. The chemistry behind the process is not yet known. Many factors have been attributed to causing or related to the onset and degree of yellowing. These include:

The purpose of this work was to express a facile method to fabricate microcapsules containing linseed oil with melamine-urea-formaldehyde (MUF) shell in the presence of polyvinylpyrrolidone (PVP) as an emulsifier. These microcapsules may be used in self-healing coating formulations.

In this work, different types of PVP (i.e., PVP with different molecular weights or K values) were used as emulsifiers and colloid protectors to encapsulate linseed oil in an MUF shell. Moreover, the effect of agitation rate on the morphology of the microcapsules was investigated. Microcapsule morphology and particle size distribution were evaluated using optical microscopy and scanning electron microscopy. Thermal studies were performed using a thermo-gravimetric analysis technique and chemical structure of materials was characterized by using Fourier transform infrared analysis.

In this work, microcapsules with a regular spherical shape and a shell thickness of about 330 nm were fabricated. The results revealed that the use of PVP in the fabrication of MUF could facilitate the synthesis process by eliminating the necessity of pH control during the reaction. In fact, the pH of the reaction media must be precisely controlled in conventional processes. The yield of microencapsulation was found to be 86.5 per cent when a high molecular weight of PVP (PVP K-90) was used. It was also found that the surface morphology of microcapsules became smoother when PVP K-90 was used. The results showed that the surface roughness and the average particle size decreased with an increase in stirring intensity. Mean diameter of the prepared microcapsules ranged from 34 to 346 μmin for various synthesis conditions.

This work is limited to the encapsulation of a hydrophobic liquid (such as linseed oil) by an in situ polymerisation of amino resins.

The presented results can be used by researchers (in academia and industry) who are working in the field of fabrication microcapsules, in various applications such as pharmaceuticals, electrophoretic displays, textiles, carbonless copy papers, cosmetics, printing and self-healing materials.

PVP is considered as an environmentally friendly emulsifier. Therefore, this process is less harmful to the environment. In addition, the prepared microcapsules may be used in self-healing coatings, which helps in reducing maintenance costs for buildings and steel structures.

Ethylene maleic anhydride and styrene maleic anhydride are usually used as emulsifiers in conventional methods for the preparation of amino resin microcapsules. These methods require an intensive and precise pH control to obtain favourable microcapsules, while in the present research, a facile method was used to fabricate MUF microcapsules containing linseed oil without needing any pH control during the reaction.

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.

Polycarbonate, a polymer having extremely useful properties, was incorporated in linseed and DCO alkyds of various oil lengths. Compatibility of polycarbonate and alkyds has been investigated. It was found that though polycarbonate was compatible with glyceryl phthalate, it was not compatible with alkyds (oil modified) in general. However, small amounts (4 to 10%) of the polycarbonate could be successfully blended with alkyds particularly with the short oil alkyds. Film properties of these blends were examined and compared with plain alkyds and epoxy modified alkyds in order to determine the usefulness of the polycarbonate‐alkyd blends. It was found that polycarbonate modified alkyds, even with such a small amount of polycarbonate, were superior in film characteristics to both the plain as well as epoxy modified alkyds.

Water soluble vehicles based on unsaturated fatty acids and oils have been prepared which have gloss and are air‐drying. Resin blends have also been prepared to improve certain characteristics. Comparison of the prepared compositions regarding their evaluation as a paint vehicle has also been taken into consideration.

Polybisphenol maleate was prepared by the reaction of bisphenol diacetate and maleic acid and its molecular weight, relative viscosity, solubility and melting points were determined. Its structure was confirmed by spectral and chemical analysis. It was incorporated physically and chemically into linseed oil alkyds and resulting products were termed as physical blends and copolyesters respectively. Film properties of blends and copolyesters were studied and compared with those of plain linseed oil alkyds. It was found that copolyesters were superior in film properties to those of plain linseed oil alkyds, and blends were up to some extent.

The purpose of this study is to get much insight about the combustion and emission characteristics of partially processed high free fatty acid linseed oil, i.e. esterified linseed oil (ELO), and diesel fuel in a single-cylinder compression ignition engine.

The variable compression ratio (CR) diesel engine (3.5 kW) of CR ranging from 12:1 to 18:1 is used for the experimentation purpose. In this study, CR varied from 16:1 to 18:1 for investigating the combustion and emissions characteristics of ELO. Various features such as combustion pressure, net heat release rate and mean gas temperature are analysed. The emission characteristics such as hydrocarbon, carbon monoxide, carbon dioxide and nitrogen dioxide are investigated with different loads and CRs. The effect of an ambient temperature condition is also reported.

Results from this investigation reveal that the burning of ELO is found to be advanced for all CRs as compared to diesel fuel, whereas these features were found to be lower for a CR of 17. Emissions of ELO are found to be higher at all loads and CRs. Overall, this study provides a necessary framework to enhance further research in this area.

This investigation shows that ELO has better combustion in the first phase of combustion. However, the exhaust emissions of ELO have higher value due to improper combustion in the second and subsequent phase of combustion due to higher viscosity.

Polybisphenol phthalate was synthesized by the melt poly condensation process and its physical and spectral data were determined. It was blended in different proportion with linseed alkyds of various oil length. Film properties of these blends were studied and were compared with those of plain linseed alkyds. It was observed that chemical properties of the blends, containing 10 and 25 per cent polybisphenol phthalate were superior to those of the plain alkyds and the blends containing 50 per cent polybisphenol phthalate. The mechanical properties such as scratch hardness of the polybisphenol phthalate alkyd blends were inferior to those of the plain linseed alkyds.