Design and properties of polyarylene ether nitrile copolymers with improved elongation at break
Shuning Liu, Chenchen Liu, Zhongxiang Bai, Weixi Zhang, Lifen Tong, Xiaobo Liu
Abstract
Abstract Polyarylene ether nitrile (PEN) based on biphenol exhibits a high glass transition temperature of 216°C, a high tensile strength of 110 MPa, and low elongation at break of approximately 4%. A series of PEN random copolymers with improved elongation at break were synthesized using various bisphenol compounds and 2,6‐dichlorobenzonitrile (DCBN). The resulting PEN random copolymers exhibited a high glass transition temperature and thermal stability up to 513°C in a nitrogen atmosphere. PEN copolymers were amorphous and could easily be cast into transparent films with a tensile strength of 97.93–117.88 MPa and tensile modulus of 2187.98–2558.44 MPa. Most importantly, elongation at break of these PEN copolymers was higher than 13%. PEN copolymer films had a dielectric constant of 3.77–3.89 at 1 kHz and extremely low dielectric loss (<0.02). At the same time, the breakdown strength of PEN was in the range of 137.92–198.19 kV/mm and energy storage density was in the range of 0.32–0.68 J/cm 3 . Excellent mechanical, thermal, and dielectric properties of PEN make it possible to use them as high‐temperature resistant dielectrics to act on high‐temperature resistant insulated cables.