Well-defined semiconducting copolymers consisting of p-phenylene (PP), p-phenylenevinylene (PV), and styrylamine (SA) ternary molecular structures (PP/PV/SA copolymer) were synthesized by living anionic polymerization for the random copolymerization of 1,3-cyclohexadiene (1,3-CHD) and 4-diphenylaminostyrene (4-DAS) and the complete dehydrogenation of the 1,3 -CHD/4-DAS copolymer. To obtain PP/PV/SA copolymer, the 1,3-CHD/4-DAS random copolymer, consisting of the 1,4-cyclohexadiene (1,4 -CHD) and cyclohexadiene (CHD)-diphenylaminostyrene (DAS) structures as a prerequisite prepolymer, was prepared by the random copolymerization of 1,3 -CHD and 4-DAS with tert-butyllithium in cyclohexane. The completely dehydrogenated 1,3 -CHD/4-DAS random copolymer was achieved without decomposition of the polymer chain when 2,3,5,6 -tetrachloro -1,4 -(p+benzoquinone was used as a dehydrogenation reagent. Gel permeation chromatography, H-1 nuclear magnetic resonance, LTV/vis, and. photoluminescence analyses confirmed that the completely dehydrogenated 1,3-CHD/4-DAS random copolymer consisting of the 1,4 -CHD and CH D DAS structures was PP/PV/SA copolymer.