An optically active, m-terphenyl-based -conjugated polymer bearing carboxy groups was synthesized by the copolymerization of the diethynyl monomer bearing a carboxy group with (S,S)-2,5-bis(2-methylbutoxy)-1,4-dibromobenzene using Sonogashira reaction. The copolymer showed a weak circular dichroism (CD) in the main-chain chromophore region due to a homo-double helix formation with an excess helical handedness biased by the chiral alkoxy substituents through self-association. However, upon complexation with achiral amines, such as piperidine, the CD intensity of the polymer significantly increased resulting in the formation of a greater excess one-handed homo-double helix via hydrogen-bonded inclusion complexation with the achiral amines between each strand, leading to the amplification of the helicity. A preferred-handed homo-double helix was also induced in the polymer in the presence of nonracemic amines. The effect of the achiral and chiral amines on the homo-double helix formation was investigated by comparing the CD spectra of the polymer to those of its model dimer. (c) 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 990-999