writer：Yu Zhou, Guofei Chen,* Wei, Wang, Lihong Wei, Qiuju Zhang, Liping Song, Xingzhong Fang.*
keywords：polyimide, transparency
source：期刊
specific source：RSC Adv.
Issue time：2015年
A series of transparent polyimides was prepared from trans-1,4-bis(2,3-dicarboxyphenoxy)cyclohexane dianhydride (trans-3,30-CHDPA) with various aromatic diamines via one-step solution polycondensation. The glass transition temperatures (Tgs) of the resulting polyimides were in the range of 206–255 C. These polyimide films showed high optical transparency with cut-off wavelengths of 370–379 nm, and they exhibited good mechanical properties with tensile strengths of 65–88 MPa, tensile moduli of 1.7–2.4 GPa, and elongations at break of 4.7–7.5%. Compared with polyimides based on trans-1,4-bis(3,4-dicarboxyphenoxy)cyclohexane dianhydride (trans-4,40-CHDPA), the polyimides derived from trans-3,30- CHDPA showed higher Tg, better solubility and optical transparency due to the 3- and 4-position isomeric effect.