Abstract: | Copolymerization of (4‐hexylphenyl)allene and of (4‐dodecylphenyl)allene with carbon monoxide (1 atm) catalyzed by Rhη3‐CH(Ar′)C{C(?CHAr′)CH2C (?CHAr′)CH2CH2CH?CHAr′}CH2](PPh3)2 (A; Ar′ = C6H4OMe‐p) gives the corresponding polyketones: I‐—CO—C(?CHAr)—CH2—]n 1: Ar = C6H4C6H13‐p, 2 : Ar = C6H4C12H25‐p; I = CH2C(?CHAr′)C(?CHAr′)CH2C(?CHAr′)CH2CH2CH?CHAr′]. Molecular weights of the polyketone prepared from (4‐hexylphenyl)allene and CO are similar to the calculated from the monomer to initiator ratios until the molecular weight reaches to 45,000, indicating the living polymerization. Melting points of the polyketones I‐—CO—C(?CHC6H4R‐p)—CH2—]n (n = ca. 100) increase in the order R = C12H25 < C6H13 < C4H9 < CH3 < H. Block and random copolymerization of phenylallene and (4‐alkylphenyl)allene with carbon monoxide gives the new copoly‐ ketones. The polymerization of a mixture of (4‐methylphenyl)allene and smaller amounts of bis(allenyl)benzene under CO afforded the polyketone with a crosslinked structure. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1505–1511, 2000 |