Synthesis of sulfonated polynaphthalene, polyanthracene, and polypyrene as strong solid acids via oxidative coupling polymerization

Oxidative coupling polymerization of naphthalene, anthracene, and pyrene with FeCl3 in nitrobenzene under nitrogen gave polynaphthalene (PNP), polyanthracene (PAT), and polypyrene (PPR) in good yields, respectively. PNP, PAT, and PPR were transformed into sulfonated PNP (S‐PNP), S‐PAT, and S‐PPR by the treatment with chlorosulfonic acid in dichloromethane at 25°C for 24 h under nitrogen, respectively. The activities of S‐PPR were higher than those of S‐PNP and S‐PAT. For the hydrolysis of cyclohexyl acetate and oleyl acetate in water, activities of S‐PPR, S‐PAT, and S‐PNP were considerably higher than those of the other conventional solid acids. Rate constants of S‐PPR were 2.8 and 11.7 times larger than those of the sulfonated condensed polynuclear aromatic (S‐COPNA(PR)) resin (PR = pyrene) for the hydrolysis of cyclohexyl acetate and oleyl acetate, respectively. S‐PPR, S‐PAT, and S‐PNP were reused without significant loss of activities. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013