The development of chemically and thermally persistent blue-, and green-luminescent hybrid pi-conjugated polymers consisting of poly(phenylene-ethynylene) conjugated backbone wrapped with the rigid three-dimensional polyhedral oligomeric silsesquioxane (POSS) units was successfully achieved by means of the Sonogashira-Hagihara coupling reaction. Because of the steric effect of POSS units, the luminescence stability of the conjugated backbone was significantly enhanced. Moreover, emission color was also easily tunable only by changing the ratio of POSS moieties incorporated. (C) 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 8112-8116,2008