Polystyrene regioregularity

The crystalline composites obtained between poly(3-alkylthiophene) and polystyrene showed an enhanced conductivity (07MM6579). The preparation of regioregular poly(3-alkylthiophene) and perylene diimide derivatives composites have been reported (06MI384). The photoluminescence spectra of this type of composites exhibit a significant photoluminescence quenching of the perylene diimide derivative. This result implies that the light absorbed by the perylene diimide units could also contribute to the generation of current at the photovoltaic device. 

Monocyclopentadienyl complexes of titanium (CpTiXs) perform poorly as catalysts for ethylene or propylene polymerization, but in the presence of MAO, they polymerize styrene to stereo- and regioregular syndiotactic polystyrene, a crystalline material with very high melting point (273 °C) and glass transition temperature (100°C). In this case, the active polymerizing species is a complex (Figure 8). Each styrene monomer inserts in a secondary manner and the stereoregularity is maintained by the conformation of the last inserted unit (chain-end control). 

M. C. lovu, Jeffries-M. El, R. Zhang, T. Kowalewski, R. D. McCullough, Conducting Block Copolymer Nanowires Containing Regioregular Poly(3-Hexylthiophene) and Polystyrene. /. Macromol. Sci. Part A 2006, 43, 1991-2000. 

Alternatively, poly(3-hexylthiophene)-f>-polystyrene was prepared by anionic polymerization [247]. Mei-jer and co-workers reported the use of allyl-terminated regioregular poly(3-hexylthiophene) as a chain transfer agent in ring-opening metathesis polymerization (ROMP) of cyclooctene. Subsequent hydrogenation yielded poly(3-hexylthiophene)-f>-polyethylene [248]. 

Details on the preparation of P60Me have been reported previously (11). The weight average molecular weight, Mw, as detected from GPC, and referred to a calibration curve on polystyrene standards was 24.000 with a Mw/Mn of 1.6. All the data reported in the text are referr to the polymer obtained as residue to hot acetone extraction. The regioregularity of the polymer, as determined by H-NMR investigation, was 98% (11). 

Higashihara, T., Ohshimizu, K., Hirao, A., and Ueda, M. (2008) Facile synthesis of ABA triblock copolymer containing regioregular poly(3-hexylthiophene) and polystyrene segments via linking reaction of poly(styryl)lithium. Macromolecules, 41,9505-9507. 

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