Method for producing semiconducting single-walled carbon nanotube dispersion

A method for separating semiconducting single-walled carbon nanotubes from metallic single-walled carbon nanotubes, comprising:

• (A) preparing a single-walled carbon nanotube dispersion to be separated that contains single-walled carbon nanotubes composed of semiconducting single-walled carbon nanotubes and metallic single-walled carbon nanotubes, an aqueous medium, and a copolymer containing a constitutional unit A derived from a monomer represented by the following formula (1) and a constitutional unit B derived from a monomer represented by the following formula (3);
• and
• (B) centrifuging the single-walled carbon nanotube dispersion to be separated and then collecting a supernatant containing the semiconducting single-walled carbon nanotubes from the centrifuged single-walled carbon nanotube dispersion,
• CH2═CH—COOM (1)
• where M represents a hydrogen atom, a metal atom, or a group with a structure represented by the following formula (2):
• where R1, R2, R3, and R4 each independently represent a hydrogen atom or an alkyl group having 1 to 2 carbon atoms and optionally containing a hydroxyl group,
• CH2═CR5—COO—(CH2CH2O)q—H (3)
• where R5 represents a hydrogen atom or a methyl group, and q represents an average number of moles of an ethyleneoxy group added and is 2 to 120.

An aqueous dispersion comprising:

• semiconducting single-walled carbon nanotubes;
• and
• a copolymer containing a constitutional unit A derived from a monomer represented by the following formula (1) and a constitutional unit B derived from a monomer represented by the following formula (3),
• CH2═CH—COOM (1)
• where M represents a hydrogen atom, a metal atom, or a group with a structure represented by the following formula (2):
• where R1, R2, R3, and R4 each independently represent a hydrogen atom or an alkyl group having 1 to 2 carbon atoms and optionally containing a hydroxyl group,
• CH2═CR5—COO—(CH2CH2O)q—H (3)
• where R5 represents a hydrogen atom or a methyl group, and q represents an average number of moles of an ethyleneoxy group added and is 2 to 120.