<![CDATA[Hydrolyzed polyacrylamide (HPAM) polymer flooding is a practical chemical enhanced oil recovery method, but polymer performance can deteriorate under high salinity, elevated temperature, and high shear rate. This study presents an integrated laboratory screening workflow for five commercial HPAM polymers under reservoir-representative conditions. Polymer solutions were prepared at 500–5000 ppm and tested at shear rates of 1–1000 s⁻¹, salinities of 3,000–200,000 ppm, and temperatures up to 90 °C. Rheological screening was followed by adsorption and core flooding tests for the most suitable candidates, Polymers C and E. These two polymers were carried forward because they achieved the highest composite scores in the technical screening, combining strong viscosity retention with favorable injectivity and salinity/temperature tolerance. All polymers showed shear-thinning behavior, while salinity and temperature reduced apparent viscosity. Polymer A provided the highest bulk viscosity; however, Polymer C gave the best balance among viscosity retention, salinity tolerance, injectivity, adsorption behavior, and recovery performance. Core flooding confirmed that Polymer C at 3000 ppm produced the highest incremental recovery, approximately 10.0% in Core 1 and 8.8% in Core 2. The results show that HPAM selection should be based on integrated rheology, adsorption, and recovery testing rather than viscosity alone. The main contribution of this work to polymer technology is a transferable, six-stage integrated screening protocol that links rheological behavior, salinity and thermal tolerance, adsorption loss, and core-scale recovery response within a single laboratory workflow, providing a practical decision basis for selecting HPAM polymers for high-salinity EOR projects rather than relying on isolated viscosity or adsorption data.]]>
