Patent ID: 6916884

Claim:
A method for preparing a first generation polymer, comprising the steps of: a) carrying out a free-radical polymerization of a composition comprising: at least one ethylenically unsaturated monomer, a source of free radicals, at least one compound (I), having a transfer constant with respect to the monomer of less than 10, of general formula (IA) or (IB): a compound of formula (II) wherein: R 1 is alkyl, acyl, aryl, aralkyl, alkene, alkyne, saturated carbonaceous ring, unsaturated carbonaceous ring, aromatic, heterocycle, or a polymer chain, Z and Z 1 , which are identical or different, is alkyl, acyl, aryl, aralkyl, alkene, alkyne, saturated carbonaceous ring, unsaturated carbonaceous ring, aromatic, heterocycle, optionally substituted, a group —OR 2 wherein R 2 is alkyl, acyl, aryl, aralkyl, alkene, alkyne, saturated carbonaceous ring, unsaturated carbonaceous ring, aromatic, heterocycle, a polymer chain, —CH 2 C n F 2n+1 with n between 1 and 20, a group —CR 5 R 6 PO(OR 7 ) 2 wherein R 5 and R 6 are each separately a hydrogen atom, a halogen, an alkyl group, a heterocyclic group, a group —NO 2 , —SO 3 R 8 , —NCO, CN, R 8 , —OR 8 , —SR 8 , —NR 8 2 , —COOR 8 , O 2 CR 8 , —CONR 8 2 , —NCOR 8 2 , or C n F 2n+1 with n between 1 and 20, R 8 , which are identical or different, are alkyl, alkenyl, alkynyl, cycloalkenyl, cycloalkynyl, aryl, optionally condensed with an aromatic or nonaromatic heterocycle, alkaryl, aralkyl and heteroaryl, R 8 optionally being substituted with one or more groups, which are identical or different, selected from the group consisting of halogen, ═O, ═S, OH, alkoxy, SH, thioalkoxy, NH 2 , mono- or dialkylamino, CN, COOH, ester, amide, and C n F 2n+1 with n between 1 and 20, optionally interrupted with one or more atoms chosen from O, S, N and P, or R 5 and R 6 form, together with the carbon atom to which they are attached, a group ═O or ═S or a hydrocarbon-based ring or a heterocycle, and R 7 , which are identical or different, represent a group R 8 as defined above or they together form a C 2 -C 4 hydrocarbon-based chain optionally interrupted with a hetero atom chosen from O, S and N; a group —NR 3 R 4 wherein R 3 and R 4 , which are identical or different, alkyl, acyl, aryl, aralkyl, alkene, alkyne, saturated carbonaceous ring, unsaturated carbonaceous ring, aromatic, heterocycle, optionally substituted, and R 3 and R 4 together form an optionally substituted ring containing at least 5 members, with the additional condition that R 3 and R 4 induce a delocalizing or electron-withdrawing effect with respect to the electron density of the nitrogen atom, and p is an integer greater than or equal to 1.