Petroleum oil derived hydrocarbon resins

Petroleum oil derived hydrocarbon resins are another important class of hydrocarbon resins worth mentioning. They are derived from unsaturated hydrocarbon monomers obtained from cracking of petroleum oil. Polymerization of these monomers results in a complex mixture of various low MW copolymers and homopolymers known as petroleum-based hydrocarbon resins. Based on monomer composition in the feedstock, various grades are available ranging from liquids to hard and brittle solids. Their performance characteristics are very similar to other hydrocarbon resins and they are useful modifiers for various conventional coating systems as well as low VOC, high-solid systems. 

Chapter 2 described the vital function of polymers as film formers in paints and coatings. However, successful paint formulation needs to meet other properties such as color and opacity that the binder alone cannot provide. Pigments are one of the most important components 

Colorants are materials used to impart color, which may be either pigments or dyestuffs. Therefore, before entering into the discussion about pigments, they must be distinguished from dyestuffs. The essential difference between them is their solubility in the medium in which they are incorporated. 

More generic to the paint industry, pigments can also be defined as organic or inorganic fine-particulate solids, substantially insoluble in paint vehicles, that are used to impart certain properties to paint such as color, opacity, corrosion inhibition, mechanical properties and durability. 

Some pigments called lakes are dyes that are combined with fine, inert inorganic particles as a base or carrier, which in turn give insoluble colorant particles. On the other hand, organic pigments that do not contain an inorganic carrying base are known as toners. In 

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