Polymer useful as viscosity index improver

摘要

The present invention describes a polymer useful as viscosity index improver comprising units derived from one or more ethylenically unsaturated ester compounds of formula (I), where R is hydrogen or methyl, R1 means a linear, branched or cyclic alkyl residue with 1-6 carbon atoms, R2 and R3 independently represent hydrogen or a group of the formula —COOR′, where R′ means hydrogen or a alkyl group with 1-6 carbon atoms, units of one or more ethylenically unsaturated ester compounds of formula (II), where R is hydrogen or methyl, R4 means a 2-alkyl branched alkyl residue with 12-18 carbon atoms, R5 and R6 independently are hydrogen or a group of the formula —COOR″, where R″ means hydrogen or an alkyl group with 12-18 carbon atoms, and units of one or more ethylenically unsaturated ester compounds of formula (III), where R is hydrogen or methyl, R7 means a linear alkyl residue with 12-24 carbon atoms, R8 and R9 independently are hydrogen or a group of the formula —COOR″, where R″ means hydrogen or an alkyl group with 12-24 carbon atoms wherein said polymer comprises at least 10% by weight units derived from one or more ethylenically unsaturated ester compounds of formula (I), based on the total weight of the polymer, said polymer comprises at least 10% by weight units derived from one or more ethylenically unsaturated ester compounds of formula (II), based on the total weight of the polymer, and said polymer comprises at least 10% by weight units derived from one or more ethylenically unsaturated ester compounds of formula (III), based on the total weight of the polymer.;

主权项

1. A polymer, comprising:
at least 10% by weight, based on a total weight of the polymer, of units derived from one or more ethylenically unsaturated ester compounds of formula (I): from 20 to 55% by weight, based on the total weight of the polymer, of units of one or more ethylenically unsaturated ester compounds of formula (II):  and from 20 to 40% by weight, based on the total weight of the polymer, of units of one or more ethylenically unsaturated ester compounds of formula (III): wherein R is hydrogen or methyl, R1 is a linear, branched, or cyclic alkyl residue with from I to 6 ca bon atoms, R2 and R3 are hydrogen, R4 is a 2-alkyl branched alkyl residue with from 12 to 18 carbon atoms, R5 and R6 are hydrogen, R7 is a linear alkyl residue with from 12 to 24 carbon atoms, R8 and R9 are hydrogen, wherein units derived from ethylenically unsaturated ester compounds of formula (II)are a mixture, and the mixture comprises as R4: units having a 2-methyl branched alkyl residue, and units having a 2-ethyl branched alkyl residue, and/or units having a 2-propvl branched alkyl residue, and units having a 2-butvl or hiaher branched alkyl residue, a weight ratio of total units of the one or more ethylenically unsaturated ester compounds of formula (II) to total units of the one or mor e ethylenically unsaturated ester compounds of formula (III) is from 4:1 to 1:1 and the polymer is suitable as a viscosity index improver.