A series of poly(carbazole-quinoxaline-amide)s (PCQAs) containing phenyl and long alkyl chain as pendants was synthesized from polycondensation between a new diamine with a synthesized and several commercial dicarboxylic acids using Yamazaki's method. PCQAs had inherent viscosities and weight average molecular weights ( ) in the range of 0.48–0.62 dL g−1 and 51,600–58,500 g mol−1, respectively. These luminescent polymers are readily soluble in a variety of organic solvents and formed low-colored and tough thin films. In this study, silane modified SiO2 (mSiO2) nanoparticles were prepared, characterized and used with PCQAs in preparation of nanocomposites via solution blending method. The interfacial interaction strength between mSiO2 and the polymer–matrix enhanced thermal stability (T10%, from 463°C to 500°C) and mechanical strength (from 100 MPa to 150 MPa) for composite containing 30 wt % mSiO2 in comparison with the pure polyamide. These materials showed good ability for extraction–elimination of metal ions such as Cr6+, Cr3+, Co2+, Zn2+, Pb2+, Cd2+, and Hg2+ from aqueous solutions either individually or in the mixture at various pH. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40219.