4, 4 -Dioctyl-bithiophene

Not only limited to the PFO polymer, another fluorene-based polymer poly(9,9-dioctylfluorene-a/t-benzothiadiazole) (F8BT) is also able to discrimi-nately wrap SWNTs with larger diameters such as a (15,4) tube." It has been suggested that a stable exciplex between poly[(9,9-dioctyl-fluorenyl-2,7-diyl)-co-(bithiophene)] (F8T2) and SWNTs exists, in which the energy level matching between SWNTs and fluorene-based polymers is responsible for the chirality selectivity. 

With in situ UV-vis spectroscopy, Zagdrska and Krische [1024] found evidence to indicate a more regular structure of polymers prepared from 4,4 -dibutyl-2,2 -bithiophene and 4,4 -dioctyl-2,2 -bithiophene and modified electrochemically as compared to polymers prepared from 3-alkylthiophenes. Nevertheless, a shorter conjugation length was found. 

Platinum electrodes coated with electrochemically polymerized thiophene, 3-methyl-, 3-octylthiophene, 2,2 -bithiophene as well as 4,4 -dioctyl-2,2 -bithiophene can be used as indicator electrodes giving a cationic response to monovalent cations such as H+, Li+, Na" ", K , NH4 and showing some sensitivity to divalent cations such as and Ca [208]. 

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