Lubricating composition with improved cold thickening properties

A method for improving the cold thickening properties of a lubricating composition of Grade (X)W—(Y) according to standard SAEJ 300 in which x=0, 5 or 10 and y=8, 16, 20, 30 or 40, comprising at least one base oil, said method comprising the addition to said lubricating composition of at least one comb polymer comprising repeating units able to be obtained by polymerisation of monomers (a) of formula (I):

• in which:
• R1 is a hydrogen atom or a methyl group,
• X1 is a group chosen from among:
• —O—, —O(AO)m, or —NH—, each group A independently being a C2-C4 alkylene group and m being an integer ranging from 0 to 10,
• R2 is a polybutylene group, and
• p is equal to 0 or 1,
• the lubricating composition thus obtained having a Gelation Index according to standard ASTM D5133 of less than 6.

A lubricating composition of Grade (X)W—(Y) according to standard SAEJ 300 in which x=0, 5 or 10 and y=8, 16, 20, 30 or 40, comprising at least one base oil, a calcium-based detergent and a magnesium-based detergent, and at least one polymer comprising repeating units able to be obtained by polymerisation of monomers (a) of formula (I):

• in which:
• R1 is a hydrogen atom or a methyl group,
• X1 is a group chosen from:
• —O—, —O(AO)m, or —NH—, each group A independently being a C2-C4 alkylene group and m being an integer ranging from 0 to 10,
• R2 is a polybutylene group, and
• p is equal to 0 or 1,
• said lubricating composition having a Gelation Index of less than 6.