Cement slurries, cured cement and methods of making and use thereof

A cement slurry comprising an aqueous phase;

• a cement precursor material;
• and a hydrophilic branched star polymer, wherein:
• the hydrophilic branched star polymer is a crosslinked, polymerized reaction product of crosslinker C and hydrophilic monomer A and hydrophilic monomer B and optionally hydrophilic monomer D,
• the hydrophilic branched star polymer consists of:
• a first plurality of block copolymer segments interconnected via crosslinker C, wherein each of the block copolymer segments of the first plurality consists of hydrophilic monomer A and hydrophilic monomer B, and wherein monomers A and B are different;
• a second plurality of block copolymer segments interconnected via crosslinker C, wherein each of the block copolymer segments of the second plurality consists of hydrophilic monomer A, hydrophilic monomer B, and hydrophilic monomer D, and wherein monomers A, B, and D are different;
• or
• both, and
• monomers A, B, and D are selected from the group consisting of acrylic acid, 2-acrylamido-2-methylpropane sulfonic acid, 2-acrylamido-ethyl phosphonic acid, maleic acid, N,N-dimethylacrylamide, (3-acrylamidopropyl)trimethylammonium chloride, 2-hydroxyethyl acrylate, styrene-4-sulfonic acid sodium salt, 4-acryloylmorpholine, poly(ethylene glycol), and methyl ether acrylate.