Phosphorus-containing polyhedral oligomeric silsesquioxane/polyimides hybrid materials with low dielectric constant and low coefficients of thermal expansion

Novel phosphorus-containing polyhedral oligomeric silsesquioxane (POSS)/polyimides (PI) hybrid materials with low dielectric constant and low linear coefficients of thermal expansion (CTE) were prepared and characterized. The POSS/PI hybrid materials were synthesized with octa(aminopropyl)silsesquioxane (OAPS) and a series of phosphorus-containing polyamide acids(PAA). The PAAs were synthesized with bis(4-aminophenoxy) phenyl phosphine oxide (BAPPO), 4,4’-diaminodiphenyl ether (ODA) and 3,3',4,4'-biphenyl tetracarboxylic diandhydride (BPDA). The structures and properties of the hybrid materials were characterized. And the effect of the phosphorus-containing structure on the POSS/PI hybrid materials was discussed. The dielectric constants and CTE of the hybrid materials were remarkably lower than that of the unmodified POSS/PI films. The lowest values of dielectric constant and CTE could achieve as low as 2.64 (1 MHz) and 27.45 ppm/K. Besides, the hybrid materials also had excellent thermal properties. The highest 5% weight loss temperature of the hybrid materials was as high as 580°C under air. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 42611.