Preparation of a Polymer with Limited π-Conjugation Length: A Polymer Containing Quaterthiophene Units

Abstract

A polymer containing quaterthiophene units in the main chain was prepared by electrochemical polymerization of 1,2-bis(3′-hexyl-2,2′-bithiophene-5-yl)ethane. The obtained green film had a conductivity of 2 × 10−2 S cm−1 in oxidized states and was neutralized by immersing in methanol. The cyclic voltammograms of the neutral film showed only an oxidation process in the first cycle.

Solution processable alternating oligothiophene-PEO-block-co-polymers: synthesis and evidence for solvent dependent aggregation

“…Deuterated solvents were used as supplied (Goss). Calculated molecular weights are reported in g mol 21 . GPC analyses were performed using an ERC 7515A refractive index detector, three 5 mm Polymer Laboratories gel columns (exclusion limits 100, 10 3 , 10 5 A Ê ) and chloroform as eluent.…”

“…The white waxy solid was recovered by ®ltration, washed with hexane and dried under vacuum for 1 d to give a-(5-bromo-2-thenoyl)-v-(5-bromo-2thenoyloxy)poly(oxyethylene) (50 g, 84%). GPC (CHCl 3 ): M n ~4300 g mol 21 ; M w ~4500 g mol 21 ; PDI~1.05. 1 Magnesium turnings (22 g, 192 mmol) were heated with a hot air gun under a dry nitrogen ¯ow and rapid stirring.…”

“…The pale yellow waxy solid was recovered by ®ltration, washed with hexane and dried under vacuum for 1 d to give a-(5-bromo-2,2'-bithiophen-5'-ylcarbonyl)-v-(5-bromo-2,2'-bithiophen-5'ylcarbonyloxy)poly(oxyethylene) (10 g, 73%). GPC (CHCl 3 ): M n ~4380 g mol 21 ; M w ~4660 g mol 21 ; PDI~1.06. 1 H NMR (300 MHz, CDCl 3 ) d 3.59 (m, 175H), 3.75 (m, 4H), 4.39 (m, 4H), 6.96 (m, 4H), 7.02 (d, J~3.9 Hz, 2H), 7.64 (d, J~3.9 Hz, 2H); 13 n-Butyllithium (1.6 M, 19.8 ml, 31.6 mmol) was added dropwise to a solution of thiophene (1.33 g, 15.8 mmol) and N,N,N',N'-tetramethylethylenediamine (TMEDA) (3.67 g, 31.6 mmol) in hexane (8 ml) at rt.…”

“…M n ~13 500 g mol 21 , M w ~21 100 g mol 21 , PDI~1.56. 1 Poly[oxycarbonyl-2,2':5',2@-terthiophen-5,5@-ylenecarbonylblock-poly(oxyethylene)], 14 a-(5-Bromo-2-thenoyl)-v-(5-bromo-2-thenoyloxy)poly(oxyethylene), 3 (10 g, 4.1 mmol) was heated to 100 ³C and the reaction ¯ask purged with nitrogen for 1/2 h while stirring the melt.…”

“…The oil was dissolved in more chloroform and the product precipitated by addition of the solution to hexane to give poly[oxycarbonyl-2,2':5',2@-terthiophen-5,5@-ylenecarbonylblock-poly(oxyethylene)] which had a higher average molecular weight than the crude product (determined by GPC). Analysis of the higher molecular weight fraction: GPC (CHCl 3 ): M n ~14 360 g mol 21 , M w ~21 780 g mol 21 , PDI~1.52. 1 Poly[oxycarbonyl-2,2':5',2@:5@,2'''-quaterthiophen-5,5'''ylenecarbonyl-block-poly(oxyethylene)], 15 a-(5-Bromo-2-thenoyl)-v-(5-bromo-2-thenoyloxy)poly(oxyethylene), 3 (10 g, 4.1 mmol) was heated to 100 ³C and the reaction ¯ask purged with nitrogen for 1/2 h while stirring the melt.…”