The present invention concerns an organopolysiloxane (A) able to be obtained by the reaction, at a temperature of between 10° C. and 75° C., between—at least one compound (C) chosen from the organic compounds comprising at least one alkene or alkyne functional group, at least one of the substituents of which is an acid functional group and the organic compounds comprising at least one acid functional group and at least one alkene or alkyne functional group, at least one of the substituents of which is an electron-withdrawing group; and—at least one organopolysiloxane (B) chosen from the organopolysiloxanes comprising siloxyl units (I.1) and (I.2) of the following formulae: (I) The present invention also concerns compositions comprising said organopolysiloxanes (A) and the uses thereof. ( I ) Y a ⁢ Z b 1 ⁢ SiO 4 - ( a + b ) 2 ; ( I ⁢ .1 ) Z c 2 ⁢ SiO 4 - c 2 ( I ⁢ .2 )