2-Cyanoprop-2-yl dithionaphthalenoate (CPDN) was successfully used as the chain transfer agent to prepare polyacrylonitrile in combination with manganese(III) acetylacetonate (Mn(acac)(3)) as the initiator. The novel polymerization exhibited well living/controlled characteristics. The polymerization behavior was revealed to comply with features of reversible addition-fragmentation chain transfer polymerization process. Mn(acac)(3) played a key role as the initiator rather than the radical trapping agent in polymerization and exhibited better control performance than azo-initiator. The narrowest molecular weight distribution was 1.31 under the condition of [AN](0):[Mn(acac)(3)](0):[CPDN](0)=200:1:0.025 and AN:DMF=1:1 (V/V). Various feed ratios of Mn(acac)(3) and CPDN were also investigated in detail. (c) 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 1305-1309