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Synthesis of cardo containing asymmetric poly(ether-naphthalimide-phthalimide)s
writer:Nafeesa Mushtaq, Lala Rukh Sidra, Guofei Chen,* Yongmei Tang, Lubo Xu and Xingzhong Fang.*
keywords:asymmetry, naphthalimide, cardo based poly(ether imide), aromatic nucleophilic substitution
source:期刊
specific source:Polym. Int.
Issue time:2017年

A series of cardo based asymmetric polyimides containing bulky rigid naphthalimide and phthalimide groups were prepared from asymmetric monomer bishaloimide and bisphenols by solution polycondensation. Bishalo(naphthalimide-phthalimide) monomers containing different terminal leaving groups (Cl, F, NO2) were synthesized, and the reactivity difference of these monomerswas compared for the successful synthesis of polyimides. The inherent viscosities of the polyimideswere in the range 0.51?0.60 dL g?1 in N-methyl-2-pyrrolidone at 30 °C. These polyimides demonstrated good organosolubility and mechanical properties with tensile strengths of 93?120MPa, tensile moduli of 3.5?5.3GPa and elongations at break of 2.8%?4.3%. The polyimides showed high glass transition temperatures (Tg) ranging from330 to 363 °C. The10%weight loss (T10%) of asymmetric polyimides reached 436?500 °C in nitrogen and 417?476 °C in air. The water uptake of the polyimides was in the range 0.35%?0.72%.