Lubricating oil composition with good frictional properties

A lubricant composition having good frictional properties, comprising base oil and at least one additive having friction-modifying properties, wherein the additive having friction-modifying properties is a block copolymer which includes hydrophobic segments P and polar segments D, said hydrophobic segments being obtained by polymerization of monomer compositions which comprises

• a) from 0 to 40% by weight, based on the weight of the monomer compositions for preparing the hydrophobic segments, of one or more ethylenically unsaturated ester compounds of the formula (I):
• in which R is hydrogen or methyl, R1 is a linear or branched alkyl radical having from 1 to 5 carbon atoms, R2 and R3 are each independently hydrogen or a group of the formula —COOR′ in which R′ is hydrogen or an alkyl group having from 1 to 5 carbon atoms,
• b) from 50 to 100% by weight, based on the weight of the monomer compositions for preparing the hydrophobic segments, of one or more ethylenically unsaturated ester compounds of the formula (II):
• in which R is hydrogen or methyl, R4 is a linear or branched alkyl radical having from 6 to 30 carbon atoms, R5 and R6 are each independently hydrogen or a group of the formula —COOR″ in which R″ is hydrogen or an alkyl group having from 6 to 30 carbon atoms,
• c) from 0 to 50% by weight, based on the weight of the monomer compositions for preparing the hydrophobic segments, of comonomers,
• and the polar segments being illustratable by the formula (III):
• in which R is independently hydrogen or methyl, R7 is independently a group comprising from 2 to 1000 carbon atoms and having at least one heteroatom, X is independently a sulfur or oxygen atom or a group of the formula NR8 in which R8 is independently hydrogen or a group having from 1 to 20 carbon atoms, and n is an integer greater than or equal to 3.