Patent ID: 7214751

Claim:
A process for the preparation of a second-generation copolymer, comprising a stage of carrying out the radical polymerization of a mixture comprising: (i) a source of free radicals, (ii) at least one ethylenically unsaturated monomer, and (iii) a polymer composition, said polymer composition (iii) being obtained by a process comprising a non-photoinitiated radical polymerization stage employing a composition comprising: at least one ethylenically unsaturated monomer; at least one compound corresponding to the formula (II) below: Z 1 —C(═S)—S—S—C(═S)—Z 2 formula (II), and at least one thermally activatable source of free radicals other than the compound of formula (II), where, in the formula (II): Z 1 and Z 2 are identical or different and each represents a radical selected from: (i) an alkyl, haloalkyl, perfluoroalkyl, alkenyl, alkynyl, acyl, aryl, arylalkyl, arylalkenyl or arylalkynyl group, or a carbonaceous ring or a heterocycle, or a polymer chain; (ii) an —OR 3 radical, in which R 3 is selected from: an alkyl, haloalkyl, perfluoroalkyl, alkenyl, alkynyl, acyl, aryl, arylalkyl, arylalkenyl or arylalkynyl group, or a carbonaceous ring or a heterocycle, or a polymer chain; a —CR A R B PO(OR C )(OR D ) group, in which: R A and R B each represent, independently of one another, a hydrogen atom, a halogen atom, a perfluoroalkyl group, a carbonaceous ring or a heterocycle, or else an —NO 2 , —NCO or —CN group or a group selected from —R E , —SO 3 R E , —OR E , —SR E , —NR E R F , —OOCR E , —CONR E R F or —SO 3 R E , in which R E and R F each independently represents an alkyl, alkenyl, alkynyl, aryl, arylalkyl, arylalkenyl or arylalkynyl group; or R A and R B together form an ═O or ═S group; or R A and R B form, together with the carbon atom to which they are attached, a hydrocarbonaceous ring or a heterocycle; and R C and R D each represents, independently of one another, an alkyl, alkenyl, alkynyl, aryl, arylalkyl, arylalkenyl or arylalkynyl group; or R C and R D together form a hydrocarbonaceous chain comprising from 2 to 4 carbon atoms optionally interrupted by an —O—, —S— or —NR G — group, where R G represents an alkyl, alkenyl, alkynyl, aryl, arylalkyl, arylalkenyl or arylalkynyl group; or (iii) an —NR 4 R 5 group, where: R 4 and R 5 represent, independently of one another, a radical selected from an alkyl, haloalkyl, alkenyl, alkynyl, acyl, ester, aryl, arylalkyl, arylalkenyl or arylalkynyl group or a carbonaceous ring; or R 4 and R 5 together form a hydrocarbonaceous chain comprising from 2 to 4 carbon atoms optionally interrupted by an —O—, —S— or —NR H — group, where R H corresponds to one of the definitions given above for the R E group, wherein the second-generation copolymer is a block copolymer.