Macromolecules, Vol.41, No.6, 1919-1928, 2008
Cyclopolymerization of N,N-dipropargylamines and NN-dipropargyl ammonium salts
The cyclopolymerization of polar, ionic N,N-dibutyl-N,N-dipropargylammonium bis(trifluoromethylsulfonyl)imide (M1), N,N-dimethyl-NN-dipropargylammonium bis(trifluoromethylsulfonyl)imide (M2), N,Ndipropargylmorpholinium bis((trifluoromethylsulfonyl)imide (M3), and N-propyl-N,N-dipropargylamine (M4) using five different well-defined Schrock- and trifluoroacetate-modified Grubbs-type initiators was investigated. Rubased initiators allowed for the polymerization of M1-M3 with average isolated polymer yields around 25-40%, however, poly-M[2 and poly-M3 thus prepared consisted > 95% of five-membered ring structures, i.e., (3,4-(1H-2,5-dihydropyrrolylene)vinylene)s units. In contrast, the use of the Schrock type initiator Mo(N-2,6-iPr(2)C(6)H(3))(CHMe2Ph)(OC(CH3)(CF3)2)2 allowed for quantitative polymer yields, whereas, poly-M2 prepared by the action of this initiator was based on both five- and six-membered, i.e., (3,5-(1,2,5,6-tetrahydropyridinylene)methylidene) cyclic units. Polymers were synthesized with molecular weights M-n < 21800 g/mol and polydispersity indices in the range of 1.04 < PDI < 1.37 and 1.01 < PDI < 1.08 with Ru- and Mo-based initiators, respectively. They were additionally investigated for their thermal stability and ionic conductivity. Finally, the solvatochromic behavior of the polymers prepared was studied. Particularly, solutions of poly-M1 prepared by the action of Ru-based initiators displayed a high sensitivity toward traces of water in N,N-dimethylformamide.