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Terpenes are the major components of resin, and of turpentine produced from resin. The name "terpene" is derived from the word "turpentine". In addition to their roles as end-products in many organisms, terpenes are major biosynthetic building blocks within nearly every living creature. Steroids, for example, are derivatives of the triterpene squalene.

The raw material terpenic resins, or polyterpenes are the group of glass-like oligomers based on natural product sourced feedstocks such as alpha and beta pinene, di-pentene, di-limonene and di-carene. After rosin and rosin esters, terpenic resins offered one of the earliest sources of resinous products used for tackification of rubber

The origin of these products was the polymerization of fractions of turpentine obtained from pine gum. More recently, the principal sources of feedstock have been turpentine, a byproduct of kraft paper pulping and di-limonene, a byproduct of citrus juice production. The thermoplastic terpene phenolic resin has a high terpene level which exhibits excellent tackifying, flexibility, and compatibility properties for use in numerous polymers for adhesives. Some are designed for tackifying hot melt adhesives to provide superior adhesion and thermal-stability properties. A styrenated terpene resin especially formulated to a medium-range softening point. It has excellent compatibility with a variety of thermoplastic rubbers and elastomeric polymers which are used in pressure sensitive and disposable adhesive applications. Like C5 hydrocarbon resins, which were developed originally as a synthetic analogue of polyterpenes, the basic polymer chemistry is one of Lewis Acid catalysis of isoprenoid structures. And, as in the case of their C5 substitutes, low level aromatic modification, usually styrene, has been found to produce beneficial improvements for certain applications, principally hot melts based on EVA and BCPs. The beta pinene-based terpene resins are generally recognized as having better tack promotion compared to their alpha pinene counterparts. The beta polyterpene resins have been the reference tackifier for pressure sensitive adhesives, particularly in combination with natural rubber for many years, but high raw material costs have substantially limited fit vis-à-vis substantially lower cost C5 hydrocarbon based tackifiers.

Terpene phenolics are used as tackifiers for rubber, such as neoprene and thermoplastic polymers such as EVA. Unlike the alkali phenol-based phenolic resole tackifiers, the terpene phenolics do not complex with metal oxides. Therefore, they do not provide the elevated temperature peel or sheer strength properties important in applications, such as adhesives for decorative laminates. In neoprene and EVA systems, they impart a high degree of tack, extended open time, and contribute plasticizing action. They are also very effective when used with natural and reclaim rubber since their use upgrades or increases the bond strength heat resistance of the adhesives as well as providing specific adhesion to metallic surfaces. Their wide compatibility and solubility characteristics also enable them to be used as modifiers in a host of adhesive systems. Their thermoplasticity makes them well suited for use in EVA based hot melt systems, especially where high levels of grab or hot tack are required and where difficult-to-bond substrates are encountered.