Effects of quinoline on the imidization temperature and properties of polyimide

Polyimide (PI) with excellent mechanical, thermal, dielectric properties which has been widely applied in electronics, automotive, high-speed rail and chemical industrie. However, the high curing temperture limited its application in the micro-electronic areas. To address this issue, quinoline (QL) with uique catalytic effect was employed in low temperature curable PI The changes in chemical structure of the PI films at different temperature was confirmed by FTIR spectroscopy with controlled addition of QL. The effects of QL content on the electrical, thermal and mechanical properties of polyimide were discussed as well. It was found that PI-1.5 has been proved with the best property which exhibited high imidization rate of 99.6% at 200 °C, dielectric constant of 3.20 and a dielectric loss of 5.06 ⅹ10-3 (1 MHz). Besides, the Young's modulus of as much as 1.66 GPa, elongation at break of more than 145% with high tensile strength about 134 MPa have been achieved. Moreover, the T5 is more than 545 °C and the glass transition temperature is higher than 376 °C. The developed low temperature curable PI is expected to be applied in the advanced electronic packaging such as fan-out wafer package, insulation, interlayer dielectric and so forth.