The bands for the PCPP monomer unit are 2246-2238 (w, CN), 1752-1733 (s, C=O), and 1252-1226 cm -1 (m, C-O). Benzene rings of both monomers show ring stretching bands at 1500-1400 cm -1 as well as a doublet 824-715 cm -1 , associated with C-H out of plane deformations. These bands can be readily identified in styrene copolymers with PCPP monomers containing cyano and carbonyl electron withdrawing groups .