Thiophene → 3,4-Ethylenedioxythiophene

Participants

Reaction Conditions

Reaction Steps

Block copolymers of EDOT with poly(propylene glycol), Poly(EDOT-block-PG), were synthesized from EDOT and a low molecular weight poly(propylene glycol) (PPG) oligomer following a two-step method in Example 1. PPG (MW=1500) was reacted with 2-thiophene carbonyl chloride in the presence of pyridine to form a di-thiophene derivative macromonomer PPGdTh. This macromonomer was then copolymerized with ethylenedioxythiophene (EDOT) in the presence of an oxidizing agent and a suitable counterion. This second step was preferably conducted in diffusion-controlled conditions to avoid the homopolymerization of thiophene; for example, a solution of the PPGdTh (2×10−1 M) in 1-pentanol was mixed with a solution of sodium persulfate (2×10−1 M) and poly(para-styrenesulfonate) in water. To this mixture a diluted solution of EDOT in 1-pentanol (10−2 M) was added dropwise under strong stirring at 80° C. The product was filtered to eliminate the homopolymer and then extracted with water to eliminate unreacted monomer and byproducts.

Provenance & Evidence