To achieve the required HLB of 11.5, what proportion of Tween 60 (HLB 14.9) and Span 20 (HLB 3.7) should be blended?

Answer 1

Assume you need "x" fraction of Tween 60 (HLB 14.9). Therefore fraction of Span 20 (HLB 3.7) needed is (1-x) since there are only two components.

x.14.9 + (1-x).3.7 = 11.5

14.9x + 3.7 -3.7x = 11.5

11.2x = 11.5-3.7 = 7.8

x = 7.8/11.2 = 0.70 (or 70%)

1-x = 0.3 (or 30%)

You mix 70% Tween 60 with 30% Span 20 to achieve the desired HLB of 11.5