The miscibility and specific interactions in poly(2,2,3,3,3-pentafluoropropyl methacrylate-co-4-vinylpyridine) (PFX, X = 0, 28, 40 or 54. denoting the mol% of 4-vinylpyridine unit in the copolymer)/poly(p-vinylphenol) (PVPh) blends have been studied by differential scanning calorimetry (DSC), atomic force microscopy (AFM), Fourier transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). DSC studies show that PFO is immiscible with PVPh, and the presence of a sufficient amount of 4-vinyipyridine units in the copolymer produces miscible blends. AFM images also clearly show that the blends change from heterogeneous to homogeneous upon the incorporation of 4-vinylpyridine unit into the copolymer. FTIR and XPS show the existence of inter-polymer hydrogen bonding between PFX and PVPh. The intensity of the inter-polymer hydrogen bonding increases with increasing 4-vinylpyridine content in the copolymer.