Hyperbranched Star Monomer: A New Strategy to Improve HPAM in Harsh Environments

The thickening properties of water-soluble polymers, such as partially hydrolyzed polyacrylamide (HPAM), are generally compromised under high salinity and temperature conditions. The resulting loss of viscosity limits their applications or necessitates the use of large quantities of polymers, making some processes economically unviable. In this study, we present the design and synthesis of a new star macromonomer capable of minimizing the viscosity loss of HPAM in harsh environments. The macromonomer was designed and prepared by using a Boltorn H30 core and a PEGMA500 shell. The incorporation of a vinyl group into the structure allowed this star system to be used as a ter-monomer in HPAM synthesis. The resulting ter-polymer was characterized by NMR and SEC. Rheological studies confirmed the potentiality of the macromonomer as an HPAM viscosity enhancer due to interactions between the hyperbranched macromonomers. This novel macromonomer could be explored in various applications requiring thickening aqueous systems in harsh environments, such as improved oil recovery processes with greater sustainability, among others.