One emulsifier or two? - Chemists Corner

Formulating

One emulsifier or two?

Posted by AlexV on January 21, 2021 at 2:02 pm

I make body and face creams only with one emulsifier (polawax gp200) and beeswax for hardness.

Is it necessary to add second emulsifier for stability to the formula or one emulsifier is enough?

Microformulation replied 3 years, 10 months ago 8 Members · 12 Replies
12 Replies

Pattsi

Member
January 21, 2021 at 2:10 pm

It’s not 100% necessary.
Do you encounter any problem with only one emulsifier or not?
OldPerry

Member
January 21, 2021 at 2:12 pm

Whether you need another emulsifier or not depends on whether your product is stable. If the formula is stable with a single emulsifier, you don’t need another one. If it’s not, adding an additional emulsifier may improve stability.
AlexV

Member
January 21, 2021 at 2:12 pm

Pattsi said:

It’s not 100% necessary.
Do you encounter any problem with only one emulsifier or not?

Thank you! After 3 months the appearance of the emulsion seems stable.
AlexV

Member
January 21, 2021 at 2:14 pm

Perry said:

Whether you need another emulsifier or not depends on whether your product is stable. If the formula is stable with a single emulsifier, you don’t need another one. If it’s not, adding an additional emulsifier may improve stability.

Thank you Perry! Does beeswax and corn starch increase stability or not?
OldPerry

Member
January 21, 2021 at 2:44 pm

Maybe, maybe not. It depends on the system.
ngarayeva001

Member
January 21, 2021 at 8:02 pm

I would say, if you are not planning to run stability test and cost isn’t an issue pair it.
Pharma

Member
January 21, 2021 at 8:44 pm

From what I could find out, Polawax GP-200 is a blend of cetearyl alcohol and PEG-20 stearate. Though fatty alcohols are not emulsifiers in the proper sense, their combination with certain o/w emulsifiers such as PEG-derivatives does act like a blend of two emulsifiers. In other words, you already use two and not one .
Bill_Toge

Member
January 21, 2021 at 10:03 pm

as a rule I tend to use two, one with low HLB and one with high HLB

where possible and appropriate, I tend to add a cationic or anionic as well, just to be sure
AlexV

Member
January 21, 2021 at 10:06 pm

Thank you ALL of you for your precious help and advices. I will stay with polawax, at least for now!
MariaSelma

Member
January 24, 2021 at 10:29 pm

Bill_Toge said:

as a rule I tend to use two, one with low HLB and one with high HLB

where possible and appropriate, I tend to add a cationic or anionic as well, just to be sure

can you please show me some exemples of Low HLB and High HLB emulsifier ?
Pharma

Member
January 25, 2021 at 5:40 am

HERE you go :smiley:
Microformulation

Member
January 25, 2021 at 1:36 pm

https://www.dropbox.com/s/lw3qyfzgs4i4r9b/HLB_system_Crodas_Time_Saving_Guide_to_S%282%29.pdf?dl=0