Two fluorinated monomers M1 and M2 based on pentafluorostyrene, are synthesized via an aromatic nucleophilic substitution reaction (SNAr) at room temperature, with high yields of up to 90%. Subsequently, M1 and M2 are converted to fluorinated poly(aryl ether)s through thermo-crosslinking. Among the two polymers, cured M2 possessing higher fluorine content, demonstrates superior overall performance with a 5% weight loss temperature (T