摘要 |
<p>A graft copolymer based on a component a) consisting of silica which has been reacted with an unsaturated silane, and a polymer component b) containing sulphonic acid is proposed. The silica used is preferably a nanosilica and the unsaturated silane is an ethylenically unsaturated alkoxysilane. The component b) is represented by a copolymer based on AMPS and a further ethylenically unsaturated monomer. The polymer according to the invention, which as a rule is a nanocomposite, is outstandingly suitable as an additive in construction chemistry applications and in the development, exploitation and completion of underground mineral oil and natural gas deposits, its effect as a water retention agent being particularly advantageous at high salinities and increased temperatures.</p> |