surfactants mixing order - Chemists Corner

Tagged: capb, cdea, formulation, sles, succinate

Formulating

surfactants mixing order

Posted by esmail on February 22, 2019 at 8:39 am

hello

i am a chemist(but not a such good one ) and trying to make liquid hand wash. i’m new in this filed and in this site too

i have some formulations that all of that says to mix surfactants in this order:

SLES

CAPB

some citric acid(0.1%)

CDEA

disodium laureth sulfosuccinate

is this theorically right (i read a post by perry in his website that tells add CAPB at the end)? if not, so whtat is the correct procedure to mixing that 4?

and could someone tell me please how pH affects (if it is) salt thickening?

sorry about my terrible english

smok replied 5 years, 8 months ago 5 Members · 9 Replies
9 Replies

LisaS

Member
February 22, 2019 at 7:41 pm

I would do some research into how pH can affect the anionic charge at the headgroup, since micelle packing relies on this, and greater packing allows for changes in shape to form a gel.
ngarayeva001

Member
February 22, 2019 at 9:07 pm

I totally agree with Perry as learned it myself via trial and error. CAPB goes in the end.

Start with SLES and sulfosuccinate, then mix Cocamide DEA with a little bit of water and heat it to 55-60C. It will make it clear and homogenous. Add cocamide DEA to SLES and sulfosuccinate. Add water and all other ingredients. Then Add CAPB in the very end and adjust the pH. Looking at the combination of surfactants that you have, I think you don’t need any salt.
Aziz

Member
February 23, 2019 at 3:15 am

ngarayeva001 said:

Then Add CAPB in the very end and adjust the pH. Looking at the combination of surfactants that you have, I think you don’t need any salt.

Without salt is it possible to achieve ultimate thickness . To consumers , thicker is better and thickest is the best . In case of hand wash , shower gel , shampoo etc consumers choose the thickest one , they don’t look at how much better ingredients inside the bottle .
esmail

Member
February 23, 2019 at 6:11 am

thank you so much for your replies

“To consumers , thicker is better and thickest is the best” is absolutly right in my region too but i use low percent of materials (to lowering the cost) and i have to use salt for thickening.

i have read somewhere in a book or articles that succinates are pH sensetive and in the supplier’s data sheet the proper pH for using DLSuccinate is about 5 - 9, should i take care of this? because in some steps during process pH got very high or low, is this makes trubble for succinate?

thanks for your attention
esmail

Member
February 23, 2019 at 6:34 am

LisaS said:

I would do some research into how pH can affect the anionic charge at the headgroup, since micelle packing relies on this, and greater packing allows for changes in shape to form a gel.

in practice when using SLES+CAPB we found that lowering the pH to about 5 makes solution thicker, i think because acidic pH rising concentration of H+ and also turning amphotheric surfactant into its cationic mode (more positive charges in solution at all) decrease - charg density of anionic surfactant and let them to pack together more tightly.

please correct me if thas not true
esmail

Member
February 23, 2019 at 8:01 am

ngarayeva001 said:

I totally agree with Perry as learned it myself via trial and error. CAPB goes in the end.

Start with SLES and sulfosuccinate, then mix Cocamide DEA with a little bit of water and heat it to 55-60C. It will make it clear and homogenous. Add cocamide DEA to SLES and sulfosuccinate. Add water and all other ingredients. Then Add CAPB in the very end and adjust the pH. Looking at the combination of surfactants that you have, I think you don’t need any salt.

thanks for your guid

should i add some citric acid (say 0.1%) at the early stages (after adding SLES may be)?
ngarayeva001

Member
February 23, 2019 at 9:38 am

@esmail it makes no sense because you want to adjust pH after you added all ingredients. Sometimes you don’t even need adjustment.
esmail

Member
February 23, 2019 at 10:30 am

after adding CDEA pH goes up to about 9, i guess adding acid in early stages recommended for preventing this(high alkalinity after CDEA) to hapen. is higher pH may ruin any ingredient at all or i should’nt concern about that?
smok

Member
February 24, 2019 at 4:14 pm

esmail said:

ngarayeva001 said:

I totally agree with Perry as learned it myself via trial and error. CAPB goes in the end.

Start with SLES and sulfosuccinate, then mix Cocamide DEA with a little bit of water and heat it to 55-60C. It will make it clear and homogenous. Add cocamide DEA to SLES and sulfosuccinate. Add water and all other ingredients. Then Add CAPB in the very end and adjust the pH. Looking at the combination of surfactants that you have, I think you don’t need any salt.

thanks for your guid

should i add some citric acid (say 0.1%) at the early stages (after adding SLES may be)?

I CONFIRM CAPB goes in the end.