Synchronously improved wave-transparent performance and mechanical properties of cyanate ester resins via introducing fluorine-containing linear random copolymer

A novel epoxy and fluorine-containing linear random copolymer of P(PFS-co-GMA) is synthesized from pentafluorostyrene (PFS) and glycidyl methacrylate (GMA) via RAFT polymerization, which is then performed to prepare modified bisphenol A dicyanate ester (m-BADCy) resin. Small dipole and low polarizability of C–F bond in PFS improve the wave-transparent performance of m-BADCy resin. Besides, the large free volume of P(PFS-co-GMA) and formation of semi-IPN structure simultaneously enhances the mechanical properties. The obtained m-BADCy resin with 15 wt% P(PFS-co-GMA) demonstrated the optimal comprehensive properties. ε and tanδ were 2.59 and 0.0053, respectively, lower than that of pure BADCy resin (2.97 and 0.0090). The corresponding wave transmittance (|T|²) increased from 92.9% of pure BADCy resin to 94.5%. Meanwhile, the corresponding flexural and impact strength increased to 122.4 MPa and 14.6 kJ/m², increased by 23.1% and 49.0% compared with pure BADCy resin (99.4 MPa and 9.8 kJ/m²), respectively. Graphical abstract: A novel epoxy and fluorine containing linear randomcopolymer of P(PFS-co-GMA) wassynthesized from pentafluorostyrene (PFS) and glycidyl methacrylate (GMA) via RAFTpolymerization, which was then performed to prepare modified bisphenol A dicyanateester (m-BADCy) resin. The m-BADCy resin displayed significantly improved wave-transparent performance and mechanicalproperties, while maintaining excellent thermal properties. [Figure not available: see fulltext.]