Synthesis and Evaluation of a Water-Soluble Hyperbranched Polymer as Enhanced Oil Recovery Chemical

Figure 9

Salt-resistance ((a) NaCl, (b) CaCl₂, and (c) MgCl₂·6H₂O) of HPAM and hyperbranched polymer solutions (5000 mg/L) at 20°C.

(a)

(b)

(c)