| abstract |
FIELD: polymers. n SUBSTANCE: invention relates to polyalkyl (meth)an acrylate polymer containing (a) 0 to 8 wt % methyl(meth)acrylate, (b) from 1.5 to 4.5 wt % hydroxysubstituted C2-C4-alkyl (meth)acrylate and (c) 87.5 to 98.5 wt % C6-C30-alkyl (meth)acrylates, where polyalkyl (meth)the acrylate polymer has an average molecular weight Mw, ranging from 30,000 to 130,000 g/mol. The invention also relates to the composition of an additive, the composition of a lubricating oil, the use of polyalkyl(meth)acrylate polymer as a means of improving the viscosity index, two variants of a method for improving the viscosity index and demulsibility of compositions of lubricating oils, as well as for the use of an additive composition as a means of improving the viscosity index. n EFFECT: using the present invention, it is possible to combine the functional characteristics and good demulsibility of lubricating compositions in an extremely effective way. n 16 cl, 11 tbl |