Synthesis of a Multi-Armed Hydrazide-POSS and Its Enhancement on the Salt and Thermal Resistance of Hydrophobically Associated Polymers

The viscosity and elasticity of water-soluble polymers are critical in the petroleum industry, particularly under high-temperature and high-salinity conditions. In this study, a multi-armed hydrazide-POSS (HPOSS) and a carbonyl-functionalized hydrophobic association polymer (CFHAP) were developed to create dual networks (CFHAP/HPOSS). Unlike conventional binary cross-linkers, HPOSS promoted the formation of dense and stable covalent cross-linked structures. Even at low concentrations of both CFHAP and HPOSS, CFHAP/HPOSS exhibited robust network formation with exceptional thickening properties, achieving a significantly higher viscosity of 3927 mPa·s at 2 g/L compared to the polymer's 410 mPa s and the binary cross-linking system's 2453 mPa s. Under a 40 g/L Na + solution, CFHAP/HPOSS exhibited salt responsiveness by enhancing their hydrophobic network, resulting in a viscosity of 5325 mPa s and a modulus G′ > G″. These enhanced rheological properties were further utilized to improve aqueous foam stability. The results revealed improved foam stability with an extended half-life time (8248 s), low drainage rate (0.0064 g/s maximum), and minimal bubble size distribution variation. SEM images also reveal a fully formed polymer film network, which effectively inhibits foam drainage and coarsening. Our strategy provides valuable insights into developing new materials with adjustable thickening and elastic properties. Highlights A multi-armed hydrazide-POSS is synthesized and used as a crosslinking agent. Dynamic acylhydrazone bond is used to fabricate a network with enough stability. Hydrophobic interaction is used to fabricate a network with salt responsiveness. The prepared polymer exhibits improved viscosity and elasticity.