초록 |
Transparency and thermal stability are highly desired for flexible plastic substrates. New cardo-based aromatic polyesters with both transparency and heat-resistance were prepared by a interfacial polycondensation of novel dibenzoic chloride and cardo typed aromatic diols. The resulting polymers had their glass transition temperatures ranged from 238 to 284 oC. Based on TGA data, they exhibited excellent thermal stabilities, showing 5% weight loss at 445-480 oC. They had low thermal expansion coefficients of 50-73 ppm/oC at the temperature range of 50-200 oC as well as good mechanical properties with moduli of 1831-2937 MPa. The optical transmittance for the polyester (ca. 50 µm thick) films was over 84% at 550 nm. These properties provide strong potential as plastic substrates for flexible electronic devices such as display, solar cell and e-paper. |