Hello Anita,

Here is a good hint:

Theoretically speaking, Castor oil is typically not soluble in water by itself, find out the HLB values for each emulsifer, and the HLB value closes to about 12.9 will emulsify the best, and 1.0 will be the worse.

Having many years of experience at formulating and formulations, the best method is to actually perform the test (theory is nice, but sometimes does not work).

I hope this helps,

Eugene

Hello Pradeep,

Yes, you are correct when authors mention the preparation of mixtures, and measurement of acid and ester values.  From past experience, HLB emulsifiers with values near 12.9 seemed to work quite well for most blends that I have created (oil in water blends).  This information was determined by experimentation (add a measured amount of water, and a measured amount of oil, and determine how much emulsifier is required for a homogenous blend).

Almost any blend will require actual miniturized blending in the laboratory, then extrapolation to large blends.

A reason for determining the acid value strongly depends on the type of emulsifier implemented.  For example, dimethyl dibenzyl sulphonic acid will usually outperform its sodium salt.  In this case, an acidic blend will be able to emulsify more oil in an oil in water blend than its salt.

Ester values are usually related very closely to the HLB values of nonionic surfactants (nonyl phenol ethoxylates for example).   Once again, the HLB values will get you close to the correct emulsion values, and preparing actual blends will 'fine-tune' subtleties to adjust for pH, salts, contamination, etc.

I hope this clarifies some of my comments.  Best Wishes,

Eugene