These compounds are used as synthetic base oils, and are claimed to have improved oxidative stability over some conventional base oils.
[1][2][3] Having an aromatic core, alkylated naphthalenes are better at solvating polar compounds than alkane mineral oils and polyalphaolefins.
[4][2] In the context of lubrication, alkylated naphthalenes are considered Group V base oils by the American Petroleum Institute.
[5] For 2020, demand for this class of base oil (that includes other types of Group V base oils) was estimated at 823,000 tonnes per year.
[4] Commercial examples of alkylated naphthalene oils include ExxonMobil's Synesstic series[6] and King Industries' NA-LUBE KR series.