A Facile Method for Preparing Fluorinated Poly(aryl ether)s Toward High-Frequency Low Dielectric Materials

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_5d) of 465 °C, a low water uptake of 0.17% (after immersing in boiling water for 72 h), a low dielectric constant (D_k) of 2.46 and dielectric loss (D_f) of 3.65 × 10⁻³ at 10 GHz. These properties outperform those of numerous poly(aryl ether)s and commercially available low-dielectric materials. This study provides a facile and effective method for preparing fluorinated poly(aryl ether)s tailored specifically for high-frequency communication applications.