The hydrogenation of petroleum resins (PRs) and the possibilities of using light hydrogenated PRs as components of hot-melt adhesives and pressure-sensitive adhesives have been surveyed. The theoretical aspects of hydrogenation of high molecular weight compounds and the influence of the main factors, such as average molecular mass, structure of hydrogenated moieties, catalyst support morphology, and solvent nature, on the extents of the hydrogenation and chain degradation reactions and their competition have been analyzed. Catalysts and processes for PR hydrogenation have been considered, and the appropriateness of using unsupported nanosized catalysts that mediate the process without diffusion limitations has been substantiated. The possibilities of using hydrogenated PRs in adhesive compositions with regard for compatibility with polymers and rheological and adhesion properties are described. Promising fields of research in hydrogenation of polymeric materials have been identified, including hydrogen-donor hydrogenation, in situ synthesis of sulfides in polymer solutions, particle size optimization of the active phase for hydrogenation of polymers with different average molecular masses, and highly selective hydrogenation of polymers.

Hydrogenation Process for Producing Light Petroleum Resins as Adhesive and Hot-Melt Components (Review)

Hydrogenation of indene–coumarone resin on commercial palladium catalysts, including crusted catalysts, was studied. The process parameters were optimized to reach the maximal hydrogenation of aromatic fragments with minimal thermal degradation of the macromolecules. The optimum conditions are as follows: temperature 230°C, pressure 3 MPa, resin concentration in the solvent 10–25 wt %. Comparative analysis of the activity of the tested catalysts shows that palladium on activated carbon exhibits the highest activity. The use of indene–coumarone resin as an adhesive component of polymer hot-melt and pressure-sensitive adhesives was considered. The rheology of the initial resins and adhesives based on them, the phase state of the formulations, and their adhesiveness were compared. The advantage of using the hydrogenated resin for preparing polymer adhesives based on styrene–isoprene–styrene triblock copolymer was demonstrated.

Hydrogenation of Indene–Coumarone Resin on Palladium Catalysts for Use in Polymer Adhesives

Unsupported Ni–Mo and Ni–W sulfide catalysts for the hydrogenation of polymeric petroleum resins are ex situ in a hydrocarbon solvent by the decomposition of oil-soluble bimetallic precursors. It is shown that the activity of the nanocatalysts is higher than that of conventional supported catalysts. The Mo: Ni ratio (1.5: 1) provides the maximum conversion of aromatic and unsaturated moieties of the substrate molecule. It is found that an increase in the process temperature and pressure leads to intensification of polymer chain degradation reactions. The highest degree of hydrogenation is achieved in polymeric petroleum resin solutions with a concentration of 40 wt %; further increase in concentration contributes to the inhibition of thermal degradation reactions. It is shown that the catalyst can be reused without any loss of activity; in addition, the degree of sulfiding of the active phase remains unchanged and the particles do not undergo agglomeration.

Hydrogenation of Polymeric Petroleum Resins in the Presence of Unsupported Sulfide Nanocatalysts

Comparison of thermal stability between dicyclopentadiene/hydrogenated dicyclopentadiene petroleum resin: Thermal decomposition characteristics, kinetics and evolved gas analysis by TGA/TG-MS

Electrochemical, ESR and quantum chemical study of 1‐substituted naphthalenes and their radical anions

In a previous report, it was found that some of the color components in the starting material of petroleum resin were cyclopentadiene, methylcyclopentadiene, and their dimers. In the present study, other color components than those mentioned above and the cause of coloring petroleum resin by cyclopentadiene and methyl derivative were investigated. Norbornadiene and ethylidene norbornene were found also to be color components, and the structures of some conjugated systems which color the petroleum resin were inferred from the data of ESR spectra.

Akira Hatano

Papers

Determination of Some Color Components Present in Petroleum Resin

Photooxidation reaction of naphthaldehyde

[Electrolytic reduction reaction of naphthaldehyde (author's transl)].