Oil modified polyester

Recently, the synthesis of seed oil-modified polyester with a hyperbranched polyether core was reported [32]. This methodology involved the preparation of a carboxyl-terminated prepolymer from the monoglyceride of the oil, which was condensed with phthalic and maleic anhydrides. 

An oil modified polyester resin is mixed with isocyanate, producing a polyurethane resin, which hardens slowly. The curing of the mould is accelerated by a catalyst and completed by heating to 150 T. 

As vegetable oil-modified polyesters have been studied over a long period of time, most known vegetable oils are now being utihsed to produce these polymers. Vegetable oil-based polyesters are used in almost aU the fields where a petroleum-based one can be used. These include protective coatings and paints, printing inks, varnishes and lacquers. 

In order to prepare oil modified polyester resins, the following components are required ... 

Oil-modified polyesters have been prepared by different techniques using the following methodologies. 

A large variety of seed oils have been used in the preparation of polyester. Rubber seed oil and karinotta oil were used in the preparation of air dried and oil-modified polyester resins. The resins were also prepared by the reaction of orange seed oiVJatropha curcas seed oil with glycerol and phthalic anhydride. Melon seed and rubber seed oils have also been used in preparation of polyester resins. The study shows rubber seed oil may be substituted for linseed and soybean oils in the preparation of both long and medium oil length polyester resins. It has also been found that melon seed... 

As stated in Chapter 1, modification of existing commercial polymers by physical and chemical means is one of most widely used industrial techniques for improving the properties of base polymers without the need to develop new polymers. Like other resins, polyesters may also be modified by functionalisation, copolymerisation, blending, interpenetrating network formation, and so on. The properties of oil-modified polyesters may be improved by appropriate modification with a variety of reactive chemicals and other polymeric materials. 

The presence of reactive sites such as double bonds, hydroxyl and carboxyl groups and phenyl rings in aromatic anhydride and ester linkages all provide tremendous potential for the modification of oil-modified polyester. Epoxy resins are considered to be polyols, which react with the carboxylic functions of polyester resin. The modification of oil-modified polyesters with epoxy resins results in products with excellent adhesion properties and improved water and chemical resistance. Epoxy modified polyesters are less expensive than epoxy resins. 

The molecular weight and distribution of oil-modified polyesters are generally determined by the GPC technique. The use of GPC analysis to monitor the formation of di-/mono-glyceride, and ditrimethyloPmonotrimethylol propane esters has been reported in the literature. The rheological... 

As mentioned above, oil-modified polyester resins possess a wide variety of structural compositions as they can be prepared from a large variety of vegetable oils. These vegetable oils possess different fatty acid compositions and structures. As the structure of a material determines its properties and behaviour, so these resins exhibit a wide range of properties which are... 

This structural property relationship is useful in understanding the properties expected in the resins. A brief overview of different properties of oil-modified polyester resins are presented here. Physical properties such as solubility, density, crystallinity and optical properties are mainly influenced by the nature of the vegetable oils, polybasic acids and polyols, the components present in the system. 

N. Dutta, N. Karak and S. K. Dolui, High performance at low cost blending seed oil modified polyesters with ME resins for high quahty Industrial coatings, Eur Coat 1,2006,3,42-7. 

U. Konwar and N. Karak, Hyperbranched poiyether core containing vegetable oil modified polyester and its clay nanocomposites . Polymer I, 2011, 43, 565-76. 

Infrared spectroscopy is used in the paint industry for quality control, product improvement and failure analysis, and for forensic identification purposes [8, 18-21], Paints are mainly comprised of polymeric binders and pigments in a dispersive medium. The binders are commonly alkyds (oil-modified polyesters), acrylics and vinyl polymers. Titanium oxide is the most commonly used pigment, while water or organic solvents are used as the medium. Paints may also contain other additives such as fillers (e.g. calcium carbonate) and stabilizers (e.g. lead oxide). 

Another early material, still in wide use, that formed polymer networks, was the alkyd resins. The alkyds are a group of resins which can be called oil-modified polyesters. These polymers are formed through the condensation and exchange reactions among polybasic acids, polyhydric alcohols, and fatty monobasic acids. Typical polybasic acids are phthalic acid anhydride, maleic anhydride, etc. The polyhydric alcohol may be glycerin, pentaerythritol, etc., while the fatty acids may originate in soy bean or linseed oil. A typical alkyd has the following structure ... 

Poly(methyl methacrylate) Aliphatic hydrocarbon Drying oil-modified polyester 72... 

In 1931, Kienle used Glyptal and oleoresinous paint technology to produce superior polymers that now account for about one-half of all coating resins. He obtained air-curable resins that were more flexible than Glyptals by producing oil-modified polyester resins for which he coined the acronym, alkyd, from the alcohol and acid reactants used. 

Glyptal and oleoresinous paint technology (oil-modified polyester resins) used by... 

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