treated with dendron active ester in the presence of base. Despite the insulating
nature of the polyester dendron, a device made with this dendron-modified
polythiophene functioned as a transistor, and showed moderate field effect
mobilities.
6.2 Block Polythiophenes
Because several substituted thiophene monomers undergo chain-growth polymerization in a living polymerization fashion, a lot of block copolythiophenes 42 [102,
154–162] have been synthesized by successive polymerization in one pot
(Scheme 56).
Of these block copolymers, 42a was first synthesized by McCullough and
coworkers [102]. We synthesized block copolymer 42b having both hydrophobic
and hydrophilic side chains in each segment [155]. The thin films of 42c [157], 42e
[158], and 42i [161] showed nanofiber structures after annealing, probably because
of microphase separation of the crystalline P3HT segment and the other amorphous
segment. The block copolymer 42d is a crystalline–crystalline diblock copolymer,
self-assembled into crystalline nanowires in solution. In melt-phase assembly, a
microphase-separated lamellar structure with two crystalline domains characteristic
Scheme 54 Synthesis of block copolymer of P3HT and polyethylene by ring-opening metathesis
polymerization of cyclooctene with allyl-terminated polythiophene, followed by hydrogenation
Scheme 55 Synthesis of dendron-modified polythiophene
Chain-Growth Condensation Polymerization for Controlled Synthesis of Polymers
231
nature of the polyester dendron, a device made with this dendron-modified
polythiophene functioned as a transistor, and showed moderate field effect
mobilities.
6.2 Block Polythiophenes
Because several substituted thiophene monomers undergo chain-growth polymerization in a living polymerization fashion, a lot of block copolythiophenes 42 [102,
154–162] have been synthesized by successive polymerization in one pot
(Scheme 56).
Of these block copolymers, 42a was first synthesized by McCullough and
coworkers [102]. We synthesized block copolymer 42b having both hydrophobic
and hydrophilic side chains in each segment [155]. The thin films of 42c [157], 42e
[158], and 42i [161] showed nanofiber structures after annealing, probably because
of microphase separation of the crystalline P3HT segment and the other amorphous
segment. The block copolymer 42d is a crystalline–crystalline diblock copolymer,
self-assembled into crystalline nanowires in solution. In melt-phase assembly, a
microphase-separated lamellar structure with two crystalline domains characteristic
Scheme 54 Synthesis of block copolymer of P3HT and polyethylene by ring-opening metathesis
polymerization of cyclooctene with allyl-terminated polythiophene, followed by hydrogenation
Scheme 55 Synthesis of dendron-modified polythiophene
Chain-Growth Condensation Polymerization for Controlled Synthesis of Polymers
231