ABA type block copolymers

Claim 2

An ABA type block copolymer represented by the following general formula I: wherein: two R¹s, which may be different or identical, stand for a hydrocarbyl group having 1 to 3 carbon atoms, two R²s, which may be different or identical, stand for a hydrogen atom or a hydrocarbyl group having 1 to 3 carbon atoms, M¹ stands for an acrylic ester residue represented by the following formula (a): wherein R³ is a hydrocarbyl group having 1 to 18 carbon atoms, which may or may not be replaced with an alkoxy or hydroxy group, M² stands for at least one residue selected from a methacrylic acid or ester residue represented by the following formula (b): wherein R⁴ is a hydrocarbyl group having 1 to 4 carbon atoms or a hydrogen atom; an aromatic vinyl residue represented by the following formula (c): wherein R⁵ is an hydrogen atom or a methyl group, and R⁶ is a phenyl or alkylphenyl group; or a maleimido residue represented by the following formula (d): wherein R⁷ is a hydrocarbyl group having 1 to 12 carbon atoms, or a phenyl or alkylphenyl group, and n and m each stand for a natural number of 20 to 5000.

Claim 3

A block copolymer as recited in Claim 1, wherein M² is a methacrylic acid or ester residue of said formula (b) wherein R⁴ denotes a hydrocarbyl group having 1 to 4 carbon atoms or a hydrogen atom.

Claim 4

A block copolymer as recited in Claim 1, wherein M² is an aromatic vinyl residue of said formula (c) wherein R⁵ denotes a hydrogen atom or a methyl group, and R⁶ denotes a phenyl or alkylphenyl group.

Claim 5

A block copolymer as recited in Claim 1, wherein M² is a maleimido residue of said formula (d) wherein R⁷ denotes a hydrocarbyl group having 1 to 12 carbon atoms, a phenyl group or an alkylphenyl group.

Claim 6

A block copolymer as recited in Claim 1, wherein M¹ is an acrylic ester residue of said formula (a) wherein R³ is a hydrocarbyl group having 1 to 18 carbon atoms, or a hydrocarbyl group having 1 to 18 carbon atoms which is replaced with an alkoxy or hydroxy group.

Claim 7

A block copolymer as recited in claim 5, wherein M² is a methacrylic ester residue of said formula (b) wherein R⁴ is a hydrocarbyl group having 1 to 18 carbon atoms.

Claim 8

A block copolymer as recited in Claim 5, wherein M² is an aromatic vinyl residue of said formula (c) wherein R⁵ denotes a hydrogen atom, and R⁶ denotes a phenyl group.

Claim 9

A block copolymer as recited in Claim 5, wherein M² is a maleimido residue of said formula (d) wherein R⁷ denotes a hydrocarbyl group having 1 to 12 carbon atoms.

Claim 10

A block copolymer as recited in Claim 5, wherein m denotes a natural number of 20 to 5,000, and n indicates a natural number of 20 to 5,000.

Claim 11

A block copolymer as recited in Claim 1, wherein -(M¹) n - comprises an acrylic ester residue represented by said formula (a) and an acrylic acid, methacrylic acid, aromatic vinyl derivative and/or vinyl acetate residue in an amount of below 5% by weight with respect to said acrylic ester residue.

Claim 12

A block copolymer as recited in Claim 1, wherein -(M²) m - comprises at least one essential monomeric residue selected from those of said formulae (b), (c) and (d) and an optional monomeric residue in an amount of below 5% by weight with respect to said essential monomeric residue.

Claim 13

A block copolymer as recited in Claim 1, wherein M¹ is a butyl acrylate residue, and M² is a methyl methacrylate residue.

Claim 14

A block copolymer as recited in Claim 1, wherein M¹ is a butyl acrylate residue, and M² is a styrene residue.

Claim 15

A block copolymer as recited in Claim 1, wherein M¹ is butyl acrylate residue, and -(M²) m - consists of an N-phenylmaleimido residue and a methyl methacrylate residue.

Claim 16

A block copolymer as recited in Claim 1, wherein M¹ is a 2-ethylhexyl acrylate residue, and M² is a methyl methacrylate residue.

Claim 17

A block copolymer as recited in Claim 1, wherein M¹ is a 2-ethylhexyl acrylate residue, and M² is a styrene residue.

Claim 18

A block copolymer as recited in Claim 1, which is in the form of an elastomer, sealant, packing, adhesive material, vibration-proof material, sound absorbing material, soling material or hose.

Claim 19

A method for preparing a block copolymer as recited in Claim 1, wherein an acrylic ester represented by the following formula: wherein R³ denotes a hydrocarbyl group having 1 to 18 carbon atoms, which may or may not be replaced with an alkoxy or hydroxy group, is photopolymerized using as a photopolymerization initator a dithiocarbamate compound represented by the general formula II: wherein: two R¹s, which may be different or identical, stand for a hydrocarbyl group having 1 to 3 carbon atoms, and two R²s, which may be different or identical, denote a hydrocarbyl group having 1 to 3 carbon atoms, thereby forming a polymeric intermediate comprising an acrylic ester polymer containing dithiocarbamate groups at both its ends, and at least one monomer selected from a methacrylic ester or acid represented by the following formula: wherein R⁴ is a hydrocarbyl group having 1 to 4 carbon atoms or a hydrogen atom; an aromatic vinyl represented by the following formula: wherein R⁵ is an hydrogen atom or a methyl group, and R⁶ is a phenyl or alkylphenyl group; or a maleimide represented by the following formula: wherein R⁷ is a hydrocarbyl group having 1 to 12 carbon atoms, or a phenyl or alkylphenyl group, is photopolymerized using said dithiocarbamate intermediate per se as a photopolymerization initiator.