Copolymerization of bis(chlorophthalimide)s with 2,5-dichlorobenzophenone catalyzed by NiBr2/PPh3/Zn

Copoly(phenylene-imide)s were synthesized by Ni(0)-catalyzed coupling of aromatic dichlorides containing imide structure and 2,5-dichlorobenzophenone. The route offered the flexibility of incorporating different ratios of benzophenone and imide groups in the polymer backbone in a controlled manner. The resulting copolymers exhibited high molecular weights (high inherent viscosity), and a combination of desirable properties such as good solubility in dipolar aprotic solvents and cresols, film-forming capability and good mechanical properties. Wide-angle X-ray diffractograms revealed that the polymers were amorphous. These copolymers had glass transition temperatures between 209 and 319 °C and 10% weight loss temperatures in the range of 502-543 °C in nitrogen atmosphere. The tough polymer films, obtained by casting from N-methylpyrrolidone solution, had a tensile strength range of 83-156 MPa and a tensile modulus range of 1.6-3.6 GPa.