A nitrogen-containing compound belonging to the polyamine family, obtained from the reaction between a polyol diglycidylether and piperazine, and having the following general formula: in which: - n is a whole number in the range 0 to 30, - the radical R 1 is selected from the groups with the following sub-formulae (g 1) to (g 4): • the group with formula (g 1): in which: -- x is a whole number in the range 1 to 100, preferably in the range 1 to 25, -- the radical R 3 is equally either a hydrogen atom, an alkyl radical or a hydroxyalkyl radical, containing between 1 and 4 carbon atoms, • the group with formula (g 2): in which y is a whole number in the range 3 to 8, • the group with formula (g 3): • the group with formula (g 4): in which: -- v and w are whole numbers, each in the range 1 to 4, with the condition that the sum of v and w is equal to 2, 3, 4 or 5, -- the radical R 4 is equally either a hydroxyl group, an alkyl radical or a hydroxyalkyl radical, containing between 1 and 4 carbon atoms, and -- the radical R 5 is equally either a hydrogen atom or a hydroxymethyl group (-CH 2 OH). - the radical R 2 has the following formula (g 5): in which: -- the radical R 6 is equally either a hydrogen atom, an alkyl radical or a hydroxyalkyl radical, containing between 1 and 6 carbon atoms, -- the radical R 7 is equally either an alkyl radical or a hydroxyalkyl radical, containing between 1 and 6 carbon atoms, -- the radicals R 6 and R 7 may be connected together via a covalent bond or via a heteroatom in order to form a heterocycle having 5, 6, 7 or 8 atoms when the radical R 6 is not a hydrogen atom, and in which, when n is equal to 0, the radicals R 6 and R 7 are connected together to form a piperazine cycle, the radical R 2 having the formula (g 6) below: in which the radical R 8 is equally either a hydrogen atom, an alkyl radical or hydroxyalkyl radical, containing between 1 and 4 carbon atoms. - n is a whole number in the range 0 to 30, - the radical R 1 is selected from the groups with the following sub-formulae (g 1) to (g 4): • the group with formula (g 1): in which: -- x is a whole number in the range 1 to 100, preferably in the range 1 to 25, -- the radical R 3 is equally either a hydrogen atom, an alkyl radical or a hydroxyalkyl radical, containing between 1 and 4 carbon atoms, • the group with formula (g 2): in which y is a whole number in the range 3 to 8, • the group with formula (g 3): • the group with formula (g 4): in which: -- v and w are whole numbers, each in the range 1 to 4, with the condition that the sum of v and w is equal to 2, 3, 4 or 5, -- the radical R 4 is equally either a hydroxyl group, an alkyl radical or a hydroxyalkyl radical, containing between 1 and 4 carbon atoms, and -- the radical R 5 is equally either a hydrogen atom or a hydroxymethyl group (-CH 2 OH). • the group with formula (g 1): in which: -- x is a whole number in the range 1 to 100, preferably in the range 1 to 25, -- the radical R 3 is equally either a hydrogen atom, an alkyl radical or a hydroxyalkyl radical, containing between 1 and 4 carbon atoms, -- x is a whole number in the range 1 to 100, preferably in the range 1 to 25, -- the radical R 3 is equally either a hydrogen atom, an alkyl radical or a hydroxyalkyl radical, containing between 1 and 4 carbon atoms, • the group with formula (g 2): in which y is a whole number in the range 3 to 8, • the group with formula (g 3): • the group with formula (g 4): in which: -- v and w are whole numbers, each in the range 1 to 4, with the condition that the sum of v and w is equal to 2, 3, 4 or 5, -- the radical R 4 is equally either a hydroxyl group, an alkyl radical or a hydroxyalkyl radical, containing between 1 and 4 carbon atoms, and -- the radical R 5 is equally either a hydrogen atom or a hydroxymethyl group (-CH 2 OH). -- v and w are whole numbers, each in the range 1 to 4, with the condition that the sum of v and w is equal to 2, 3, 4 or 5, -- the radical R 4 is equally either a hydroxyl group, an alkyl radical or a hydroxyalkyl radical, containing between 1 and 4 carbon atoms, and -- the radical R 5 is equally either a hydrogen atom or a hydroxymethyl group (-CH 2 OH). - the radical R 2 has the following formula (g 5): in which: -- the radical R 6 is equally either a hydrogen atom, an alkyl radical or a hydroxyalkyl radical, containing between 1 and 6 carbon atoms, -- the radical R 7 is equally either an alkyl radical or a hydroxyalkyl radical, containing between 1 and 6 carbon atoms, -- the radicals R 6 and R 7 may be connected together via a covalent bond or via a heteroatom in order to form a heterocycle having 5, 6, 7 or 8 atoms when the radical R 6 is not a hydrogen atom, and in which, when n is equal to 0, the radicals R 6 and R 7 are connected together to form a piperazine cycle, the radical R 2 having the formula (g 6) below: -- the radical R 6 is equally either a hydrogen atom, an alkyl radical or a hydroxyalkyl radical, containing between 1 and 6 carbon atoms, -- the radical R 7 is equally either an alkyl radical or a hydroxyalkyl radical, containing between 1 and 6 carbon atoms, -- the radicals R 6 and R 7 may be connected together via a covalent bond or via a heteroatom in order to form a heterocycle having 5, 6, 7 or 8 atoms when the radical R 6 is not a hydrogen atom,