Лако-красочные материалы — производство

This is the most commonly used route in alkyd resin manufacturing. Oils, being cheaper raw materials as compared to corresponding fatty acids, are naturally preferred for alkyd resins, but the oil does not react readily with acid or alcohol. Therefore, to avoid a heteroge- neous mixture of unmodified polyester and unreacted oil, first the oil […]

Chemically, all alkyds are polyesters and are derived from a poly­condensation reaction of polyhydric alcohols and polybasic acids with a certain degree of modification by some kind of oil or fatty acid. Among the important chemical reactions involved in alkyd resin technology are direct esterification of carboxylic acids with alcoholic hydroxyl groups, transesterification reactions, and […]

Alkyd resins have been used in surface coatings for more than eight decades. They have been the workhorse of the binders for solventbased architectural coatings and to a considerable extent for industrial coatings because of their low cost, good performance properties, and versatility of applications. In the beginning of the 20th century, the esterification product […]

The relatively slow drying speed of oils was the main limitation for their use in paints and coatings, and therefore for practical appli­cations, a number of oils modified either chemically and/or struc­turally were introduced to improve their drying time and other performance factors. These modifications involving reactions of oils in other resins such as alkyds, […]

There are many ways in which oils can be classified, but in the surface coating industry, oils are mainly classified according to their film for­ming ability, which is primarily governed by their degree of unsatura­tion. Therefore, oils are classified according to their iodine value (IV) as: • Non-drying oil: IV < 120 (for example, coconut […]

Natural oils, used as components of binders for surface coatings, are generally derived from oilseeds, though occasionally they are of ani­mal origin, such as fish oil. Compositionally they are triglycerides of fatty acids. They are sometimes described as fixed oils to distingu­ish them from essential oils, which are volatile aromatic oils found in some plants. […]

There is much historical evidence that plant oils and animal fats were among the first binders to be used for paints and coatings. Their easy availability and ability to form a coherent film when applied to a surface and exposed to air, which oxidizes them, have made them very attractive as a coating raw material […]

Bituminous binders are a crude type of hydrocarbon resin, gene­rally produced as a by-product during distillation of crude oil or coal. Bituminous resins, based on their chemical composition, are categorized as asphalt-based and coal-tar pitch-based products. We will briefly discuss some important bituminous binders used in coatings and related industries. Bituminous vehicles are chemically complex […]

Rosin, also known as colophony, and its derivatives are among the most important and widely used natural resins. Rosin is obtained from pine trees either by collecting exudations from the tree (known as gum rosin) or by solvent extraction of aged pine stumps (known as wood rosin). It can also be obtained as a by-product […]

In IS0 4618/3, natural resins are defined as resins obtained from a vegetable or animal origin. Natural resins have been used in coa­tings for a long time. In recent times, although technologically advan­ced synthetic resins have replaced these materials, certain natural resins have maintained their place for particular uses as modifiers. They are classified, based […]