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Comparative study of transparent polyimides derived from bis(ether anhydride)s and bis(ester anhydride)s using 2,2''-bis(trifluoromethyl)biphenyl-4,4''-diamine
writer:Yu Zhou, Guofei Chen,* Wei Wang, Liping Song, Xingzhong Fang,*
keywords:transparent, polyimides, bis(ether anhydride), bis(ester anhydride)
source:期刊
specific source:High Perform. Polym.
Issue time:2017年

Two series of polyimides (PIs) derived from bis(ether anhydride)s and bis(ester anhydride)s using 2,20-bis(trifluoromethyl) biphenyl-4,40-diamine were synthesized via solution polycondensation. The poly(ether imide)s could be formed by the conventional one-step method, while the poly(ester imide)s were only afforded by the two-step procedure.

The resulting PIs had glass transition temperatures (Tgs) in the range of 224–320C and exhibited good mechanical properties with tensile strength in the range of 80.5–96.5 MPa, tensile moduli 2.7–6.9 GPa, and elongations at break 1.5–17.3%. It was found that the PIs derived from bis(ether anhydride)s showed higher thermal stability, better solubility, and

transparency but lower Tg and higher water absorption compared with bis(ester anhydride)-based PIs due to the different ether and ester linkages.