WHAT IS WRONG??? - Chemists Corner

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WHAT IS WRONG???

Posted by filiz on September 4, 2020 at 5:01 am

Hi to everyone

I’m trying to make a shower gel but ıt does not have a gel density. First I add NaCl then I set the Ph with Citric Acid. What is the problem with its density not increasing?

here some info about my formule

Sodium Laureth Sulfate %15
aqua %77,5
Preservative %0,5
citric acid 0,05
cocamidopropyl betaine 2,5
cocamide DEA 2,5
Sodium Benzoate 0,3
NaCl 1
fragrance
aloe vera 0,2

so, what is wrong ?
I would be very happy if you can help…

Aanchal replied 4 years, 3 months ago 6 Members · 14 Replies
14 Replies

ozgirl

Member
September 4, 2020 at 5:29 am

What is the active concentration of your SLES? Your concentration of surfactant actives may be too low in your formulation.

This calculator may help.

https://makingskincare.com/surfactant-calculator/
Graillotion

Member
September 4, 2020 at 5:56 am

I am a total novice at this…but I believe you get your pH right first…then add your salt. The salt curve changes with the pH. You are trying to hit a moving target. (and you are the one moving the target…hehehe.)
filiz

Member
September 4, 2020 at 6:59 am

@ozgirl Thank you so much. I calculated it now. Total surfactant is 13. I am thinking of changing the intervals. As far as I know, there is a 6: 1: 1 ratio between SLES and other surfactants. I’m not sure if this is correct information.
filiz

Member
September 4, 2020 at 7:24 am

@Graillotion thank you. I’ll try this way and write the results here. Does it have to do with turnover and temperature? normally cold process formula
ketchito

Member
September 4, 2020 at 1:18 pm

@filiz I believe your betaine is still too low (keep in mind that it’s usually 30% active)…bring it close to 4%, and you might also have to increase the NaCl, but do that after you checked if the betaine increased worked. Also, pH should preferably be over 6, both for better interaction between betaine and SLES and to prevent turbidity (betaine behaves as a cationic at low pH).
ngarayeva001

Member
September 4, 2020 at 9:53 pm

Agree, not enough SLES
Graillotion

Member
September 5, 2020 at 3:26 am
Graillotion

Member
September 5, 2020 at 3:27 am

Changing the pH just by 1….can completely invert your salt curve. Supplier should be able to provide you with a pH based salt curve.
Graillotion

Member
September 5, 2020 at 3:29 am
Graillotion

Member
September 5, 2020 at 3:30 am

As you can see….the product I am working with…will have maximum viscosity in the range of 1.2-1.4% salt….assuming a pH of 6. Changing the pH to 5.2….crashes the system.
Aanchal

Member
September 5, 2020 at 5:07 am

Read about salt curve. Plot a curve with minimal salt and inceease in bits. It may be that any of your raw material already has salt (one supplier gave me CAPB that had some salt). Salt curve is to be plotted by you for your formulation.

Also, CAPB curve can also be plotted. It does increase viscosity but can reduce if it’s in excess.

I’m no expert, but observed these things in my formulation.
filiz

Member
September 7, 2020 at 5:42 am

@Graillotion The information you give is very valuable. thank you . last case: first I set the ph, I had to increase the salt by 0.5 for the viscosity adjustment. I’ve used 1.5 in total. but I haven’t achieved the standard density yet. I decided to change the proportion of surfactants but I am not sure in what proportions.
filiz

Member
September 7, 2020 at 5:45 am

@Aanchal thank you… Is there a resource you can share? I don’t want to overlook useful ones while searching.
Aanchal

Member
September 12, 2020 at 6:29 pm

@filiz search salt curve in this forum. There’s an article by Perry.