Radical polymerisation method performed in the presence of disulfide compounds

23:

• A process for the preparation of a polymer composition, 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:
• Z1—C(═S)—S—S—C(═S)—Z2 formula (II),
• and
• at least one thermally activatable source of free radicals other than the compound of formula (II),
• where, in the formula (II):
• Z1 and Z2 are identical or different and each represent a radical selected from:
• (i) an alkyl, haloalkyl, perfluoroalkyl, alkenyl, alkynyl, acyl, aryl, arylalkyl, arylalkenyl or arylalkynyl group, or else a carbonaceous ring or a heterocycle, or else a polymer chain;
• (ii) an —OR3 radical, in which R3 denotes a group selected from:
• an alkyl, haloalkyl, perfluoroalkyl, alkenyl, alkynyl, acyl, aryl, arylalkyl, arylalkenyl or arylalkynyl group, or else a carbonaceous ring or a heterocycle, or else a polymer chain;
• a —CRARBPO(ORC)(ORD)group, in which:
• RA and RB each represent, independently of one another, a hydrogen atom, a halogen atom, a perfluoroalkyl group, a carbonaceous ring or a heterocycle, or else an —NO2, —NCO or —CN group or a group selected from the groups
• of —RE, —SO3RE, —ORE, —SRE, —NRERF, —OOCRE, —CONRERF or —SO3RE type, in which the groups represented by RE and RF each independently denote an alkyl, alkenyl, alkynyl, aryl, arylalkyl, arylalkenyl or arylalkynyl group;
• or else RA and RB together form an ═O or ═S group;
• or else RA and RB form, together with the carbon atom to which they are attached, a hydrocarbonaceous ring or a heterocycle;
• and
• RC and RD each represent, independently of one another, a radical corresponding to one of the definitions given above for the RE group;
• or else RC and RD together form a hydrocarbonaceous chain comprising from 2 to 4 carbon atoms optionally interrupted by an —O—, —S— or —NRG-group, where RG corresponds to one of the definitions given above for the RE group;
• or
• (iii) an —NR4R5 group, where:
• R4 and R5 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
• R4 and R5 together form a hydrocarbonaceous chain comprising from 2 to 4 carbon atoms optionally interrupted by an —O—, —S— or —NRH-group, where RH corresponds to one of the definitions given above for the RE group.

31:

• The process of claim 23, wherein the ethylenically unsaturated monomer employed corresponds to the formula (I) below:
• H2C═CR1R2 formula (I),
• in which:
• R1 represents a —COOA radical, in which A denotes an alkyl, haloalkyl, perfluoroalkyl, alkenyl, alkynyl, arylalkyl, arylalkenyl or arylalkynyl group;
• and
• R2 represents a hydrogen atom, a halogen atom, an alkyl group, a haloalkyl group or an alkoxy group, it being possible for these alkyl, haloalkyl or alkoxy groups to be unsubstituted or substituted.

36:

• The polymer composition prepared by the process of claim 23, which includes living polymer chains corresponding to the formula (P) below:
• Z—(C═S)—S—[—CR1R2—CH2—]n—Y formula (P),
• in which:
• the Z radical has any one of the meanings given in claim 23 for the Z1 and Z2 groups present in the compounds of formula (II);
• the R1 and R2 groups can have different meanings within each unit [—CR1R2—CH2—] of the formula (P) and represent, within each unit [—CR1R2—CH2—], two identical or different groups;
• n denotes an integer at least equal to 1;
• and
• Y denotes a radical characteristic of the thermal initiation carried out during the polymerization of the process.

41:

• A process for the preparation of a second-generation copolymer, comprising a stage consisting in carrying out the radical polymerization of a mixture comprising:
• a source of free radicals,
• at least one ethylenically unsaturated monomer, and
• a polymer composition as claimed in claim 35.

44:

• A process for the preparation of an Nth-generation block copolymer, N being an integer greater than or equal to 2, by a radical polymerization process which comprises:
• (A) a first stage consisting in preparing a polymer composition by a process as claimed in claim 23,
• and
• (B) a number (N−1) of radical polymerization stages, each of these stages employing a mixture comprising:
• a source of free radicals,
• at least one ethylenically unsaturated monomer, and
• the polymer obtained in the preceding polymerization stage.