Novel transparent poly(arylene ether nitrile) copolymers with pendant aliphatic ring: synthesis and characterization

Two kinds of novel poly(arylene ether nitrile) copolymers (P-HFD and P-PFD) containing pendant aliphatic ring and fluorene groups were synthesized by 4, 4’-cyclohexane-1, 1’-diyldiphenol (CHDP) or 4, 4’-cyclopentane-1, 1’-diyldiphenol (CPDP), 4, 4’-(9-fluorenylidene) diphenol and 2, 6-dichlorobenzonitrile (DCBN) in this work. The inherent viscosities of these two copolymers were 0.455 and 0.576 dL g ^− 1 . The copolymers P-HFD and P-PFD exhibited good thermal property, the glass transition temperatures (T _g ) were 202.2-214.9 ^o C, and the weight-loss temperatures (T _5% ) were 421.3-433.5°C. The polymers’ films had good tensile strengths of 27.3–38.6 MPa. The result of dissolution experiment showed that the copolymers could be dissolved in some solutions at room temperature, such as NMP, DMF and CH ₂ Cl ₂ , implying that they had good solubility, they can be processed by the solution method. Additionally, the optical transmittances of these two copolymers were 68.3–76.3% at 450 nm, indicating that they have potential to be applied as the heat-resistant optical films.