Liquid laundry detergent formulation

A liquid laundry detergent formulation, comprising:

• a liquid carrier;
• a cleaning surfactant;
• and
• a cleaning booster polymer, wherein the cleaning booster polymer, comprises:
• (a) 60 to 95 wt %, based on dry weight of the cleaning booster polymer, of structural units of a monoethylenically unsaturated carboxylic acid monomer;
• (b) 5 to 40 wt %, based on dry weight of the cleaning booster polymer, of structural units of an ethylenically unsaturated monomer of formula (I)
• wherein X is selected from the group consisting of an oxygen atom and a sulfur atom;
• wherein R1 is a C2-4 alkylene group;
• wherein R2 is selected from the group consisting of a 2-(2-carboxyacrylamide)ethyl group, a vinyl group, an allyl group, an isopropenyl group, an acryloyl group, a methacryloyl group, a 2-hydroxy-3-(allyloxy)propyl group and a functional group of formula (II)
• R4—Y—R3— (II)
• wherein R3 is a C1-5 alkylene group;
• wherein Y is selected from the group consisting of an —O— and an —NR5—, where R5 is selected from the group consisting of a hydrogen and a C1-8 alkyl group;
• and
• wherein R4 is selected from the group consisting of a 2-hydroxy-3-(allyloxy)propyl group, a vinyl group, a methacryloyl group, an acryloyl group and a methacryloyloxyaceto group;
• (c) 0 to 20 wt %, based on dry weight of the cleaning booster polymer, of structural units of an ethylenically unsaturated monomer of formula (III)
• wherein A is selected from the group consisting of an —O— and an —NR5—;
• wherein each R6 is independently selected from the group consisting of a —CH2CH2O— group, a —CH2CH(CH3)O— group and a —CH2CH(CH2CH3)O— group;
• and
• wherein b is 2 to 20;
• (d) 0 to 5 wt %, based on dry weight of the cleaning booster polymer, of structural units of an ethylenically unsaturated monomer of formula (IV)
• wherein each R7 is independently selected from a —C14 alkyl group;
• and
• wherein each R8 is independently selected from the group consisting of a hydrogen and a methyl group.