Functionalized KIT-6/Terpolyimide Composites with Ultra-Low Dielectric Constant

Polyimides with low dielectric constants are important raw materials for the fabrication of flexible printed circuit boards and other microelectronic applications. As creation of voids in polyimide matrix could decrease dielectric constant, in this study mesoporous KIT-6, synthesized hydrothermally, was functionalized with 3-aminopropyltriethoxysilane (APTS) and mixed with 4,4'-oxydianiline (ODA) in the synthesis of terpoly(amic acid) using 3,3',4,4'-biphenyldianhydride (BPDA), 3,3',4,4'-oxydiphthalic dianhydride (ODPA) and 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA) and subsequently stage-cured to obtain APTS-KIT-6/Terpolyimide composites (APTS-KIT-6/TPI). The asymmetric and symmetric vibrations of imide O=C-N-C=O groups of APTS-KIT-6/TPI composites showed their peaks at 1772 and 1713 cm(-1). The dielectric constant decreased with the increase in KIT-6 loading from 2 to 4%, but increased at higher loadings, and at 4% loading it was 1.42. Its tensile strength (103 MPa), tensile modulus (2.5 GPa), and percentage elongation (8.2) and high thermal stability (>540 degrees C) were also adequate for application in microelectronics such as flexible printed circuits. (c) 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40508.