Days Polymer AN-125 SH , 2000 ppm Alpha olefin sulfonate, wt% 0.0 0.0 0.4 0.6 1.0 Acid to alkali concentrations, wt% 0 : 0 0.6:1.0 0.4:0.7 0.6:1.0 0.8:1.3 1 - - - - - 15 - - - - - 30 - - - - -

- denotes clear solution

Table 4: Summary of acid-alkali-surfactant-polymer interaction test during 30 days at 80°C.