BEHAVIOR OF SILICONE SURFACTANTS 99 A 14003 12t•0 --El-- ABIL50% + PG50% --e-- ABIL70% + PG30% --A-- ABIL90% + PG10% I • I ' I ' I ' I 0 5 10 15 20 SHEAR RATE d/S) ' I ' I' 25 30 A G I I I G --m-- DCS(Y'• + PG50% --e-- DC70% + PG30% --A-- DC90% + PG10% I ' I ' I ' I ' I ' I ' I ' I 0 5 10 15 20 25 30 35 SHEAR RATE (1/S) Figure 8. A. Changes in viscosity with shear rate in mixtures of Abil WE 90 with 10%, 30%, or 50% propylene glycol (PG) at constant temperature (1• ø _+ 1øC). B. Changes in viscosity with shear rate in mixtures of DC Q2-5200 with 10%, 30%, or 50% propylene glycol (PG) at constant temperature (15 ø _+ 1 øC). CONCLUSIONS The choice of surfactant (DC Q2-5200 or Abil 'WE 09) can influence viscosity of an emulsion. Our study shows that DC Q2-5200 exhibits a tenfold increase in viscosity as compared to Abil 'WE 09. The influence of temperature shows changes more notable in

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