US Patent 9896617 Polymer compositions

A method of enhancing oil recovery in a subterranean reservoir is disclosed. In one embodiment, the method comprises providing a wellbore and a polymer suspension. The polymer suspension comprises a powder polymer having an average molecular weight of 0.5 to 30 Million Daltons suspended in a water soluble solvent having an HLB of greater than or equal to 8 and selected from a group, at a weight ratio of 20:80 to 80:20. The method comprises providing an aqueous fluid, mixing a sufficient amount of the polymer suspension in the aqueous fluid for the polymer to be hydrated resulting an injection solution in less than or equal to 4 hours, and injecting the injection solution into the wellbore. The injection solution contains a polymer concentration ranging from 100 ppm to 50,000 ppm and has a filter ratio of less than 1.5 at 15 psi using a 1.2 μm filter.