Abstract: Hydraulic fracturing fluids include an aqueous fluid, an acrylamide-based polymers, and a hyperbranched crosslinker that crosslinks the acrylamide-based polymer to form a crosslinked gel. The hyperbranched crosslinker includes a hyperbranched polyethyleneimine polyoxiranylalkanol having a weight-average molecular weight from 10 kDa to 1500 kDa. The hyperbranched crosslinker may be a product of reacting a hyperbranched polyethyleneimine with an oxiranylalkanol to obtain the hyperbranched polyethyleneimine polyoxiranylalkanol. In examples, the oxiranylalkanol is glycidol. Methods for preparing the hydraulic fracturing fluids and methods for treating subterranean formations with the hydraulic fracturing fluids are disclosed.

Abstract: This invention relates to an antibacterial polymer-modified particle comprising a particle core, wherein a polymer is covalently bound to the particle core via a linker and said polymer comprises a branched, amphiphilic cationic polyalkylene imine backbone having amine or amino functional groups and wherein optionally all or some of the amine or amino groups of the polymer have been further reacted with amphiphilic cyclic carbonates carrying a quaternary ammonium group under formation of a urethane bond. In a preferred embodiment the core is a silica core functionalized with the polyelkyleneimine. The invention also relates to methods of making such particles and their use in water disinfection applications.