Hydrocarbons are soluble in aromatic solvents such as toluene and xylene. Aliphatic petroleum resins and terpene resins are also soluble in aliphatic solvents such as hexene. Coumarone-indene resins are mostly soluble in acetone. Most commercial hydrocarbon resins produced from olefinic feedstocks are synthesized via carbocationic polymerization. The polymerization of monomers from hydrocarbon resins is typically carried out by either the direct addition or catalyst to a hydrocarbon fraction or by the addition of feed to a solvent-catalyst slurry or solution.
Most commercial manufacturers use a continuous polymerization process as opposed to a batch process.
Obtained from this process are feedstocks composed of aliphatic, aromatic, and cycloaliphatic olefins and diolefins, which are subsequently polymerized to yield resins of various compositions and physical properties. These resins may then be further hydrogenated for specific physical properties such as color. Isoprene and cyclopentadiene may be present in small quantities. The objective was to demonstrate that application properties are a function of the tackifier as tested according to standard PSTC and ASTM methods commonly used in the PSA trade. All formulations were prepared from a single batch of natural rubber that was milled at room temperature for 30 minutes.