Potassium Ion Mediated Living and Controlled Anionic Polymerization of 2-Vinylnaphthalene (2VN). Synthesis of P2VN-b-poly(α-methylstyrene) and P2VN-b-poly(9,9-dimethyl-2-vinylfluorene) Block Copolymers

Abstract

The anionic polymerization is reported of 2-vinylnaphthalene (2VN) initiated with potassium naphthalide (K-Naph), potassium 1,1,4,4,7,7,10,10-octamethyl-1,2,3,4,7,8,9,10-octahydronaphthacene (K-OMOHN), and α-methylstyryldipotassium oligomers (AMS-K2) in tetrahydrofuran at −78 °C. Narrow molecular weight distributions are obtained with good agreement of calculated and observed molecular weights. It is also possible to prepare poly(2-vinylnaphthalene) (P2VN) of very high molecular weight (as high as 90 000) and narrow polydispersity indices (PDI as low as 1.06). Under the above conditions, the P2VN-K2 has a shelf life exceeding 1 h as indicated by polymerization resumption experiments giving P2VN with statistical narrowing of the molecular weight distribution. The living character of the P2VN-K2 dianion was also demonstrated by the synthesis of narrow molecular weight distribution poly(α-methylstyrene)-b-P2VN-b-poly(α-methylstyrene), P2VN-b-poly(α-methylstyrene)-b-P2VN, and poly(9,9-dimethyl-2-vinylfluorene)-b-P2VN-b-poly(9,9-dimethyl-2-vinylfluorene) triblock copolymers and by quantitative end-functionalization with 1,4-bis(bromomethyl)benzene.