ALS formula thickening problems again!

Formulating

ALS formula thickening problems again!

Posted by billichemist on April 6, 2015 at 10:23 pm

Hello there!

I have had a bit of trouble with thickening my ALS/CAPB formula… it is all nice and thick up until i add my essential oil blend in. (it is meant to be a simple handwash with a citrusy EO blend)

I have tried adding salt, adding more CAPB, adding more ALS and adding carbopol (though i am trying to avoid this) to no avail..

Any other suggestions? I am at a loss

billichemist replied 9 years, 2 months ago 10 Members · 28 Replies
28 Replies

OldPerry

Member
April 6, 2015 at 11:21 pm

Add less oil. Also, consider using some solubilizer nonionic surfactant like Polysorbate.

What benefit are you trying to provide by including the oils?

You are running into a simple fact of surfactants, they are really good at removing oils. So trying to put oils in the formula or even getting it to deliver to the surface is extremely difficult.

If it is just for marketing reasons, cut the level down to 0.1%. That should stop the negative viscosity effect.
DavidW

Member
April 7, 2015 at 2:00 am

How much oil (%) are you trying to put in? Perry is correct. You can also try premixing your oils (at a low percent) into the ALS. Some oils will go in and some won’t.
billichemist

Member
April 7, 2015 at 2:22 am

Hi @perry and @davidW thank you for your responses. I am trying to add in 0.65% of an EO blend that is high in citrus oils…

I also have an alcoholic extract in the formula, albeit at a low percentage.. is alcohol known to be incompatible with such surfactant formulas?
billichemist

Member
April 7, 2015 at 4:12 am

hi guys, I tried adding 1:1 polysorbate 20 premixed with the EO blend, but it didn’t work! Also, reducing the pH from 7.5 to ~6.5 also drastically reduced the viscosity!

should i be using more polysorbate? or a combination of polysorbate 20 and Cremophor?
billichemist

Member
April 7, 2015 at 6:07 am

this extra information might help…

it is a ALS, Cocoamindopropyl Betaine and Cocoamide DEA system. its not my formula, i have merely been using this as a template/base. is this template even worth working off?
DavidW

Member
April 7, 2015 at 1:30 pm

IF you are using polysorbate, you need to start at 3 parts poly to each 1 part oil. However, the polysorbate will reduce viscosity most likely and then you have to ry thickening it back up.
Ayla

Member
April 7, 2015 at 3:00 pm

I think 0.65% of EO is a bit high.

You could try Solubilisant LRI from Sensient. It worked well for me.
OldPerry

Member
April 7, 2015 at 6:51 pm

7.5 pH? That seems pretty high.

I think if you could list your entire formula and % you might get better suggestions.
billichemist

Member
April 7, 2015 at 9:36 pm

aqua - 48%

glycerine - 5%

ALS - 20%

Adjust to pH 4.5

Cocoamide DEA - 15%

Phenoxyethanol - 0.55

Fragrance - 0.65%

alcoholic extracts - q.s.

Cocoamidopropyl betaine - 11%
OldPerry

Member
April 7, 2015 at 10:13 pm

Wow, that’s a lot of amide and betaine in the formula!

More typical would be…

ALS = 15% (on an actives basis)

Cocamidopropyl betaine = 5% (on an actives basis)

Most companies avoid DEA containing ingredients because they have to be listed as carcinogens on California’s Prop 65 list. In this formula you wouldn’t really need it.
billichemist

Member
April 7, 2015 at 10:19 pm

So i should remove DEA completely and thicken with salt?
ozgirl

Member
April 7, 2015 at 10:40 pm

I have never seen Cocamide DEA used at more than about 2% in this type of formula. You can replace Cocamide DEA with Cocamide MEA.
Venera

Member
April 8, 2015 at 12:51 am

I well go with Sepigel 305 without changing the initial formula. It’s going to help with thickening as well as with the emulsifying the oils. I we’ll start with 0.50 %. You’ll see if you need higher viscosity you can increments 0.25% up to desired viscosity. You can go as high as 1.50-3.00 % or more if needed.
OldPerry

Member
April 8, 2015 at 1:02 pm

You don’t need the Cocamide DEA. You can get plenty of thickening with the ALS / Betaine blend plus salt. No other thickening system required.
Chemist77

Member
April 8, 2015 at 3:39 pm

Agree with @Perry, Cocamide DEA just modifies the salt curve rather than being a thickener itself. You can avoid it altogether and either go Perry’s way or @Venera‘s, though I would be interested to know the final performance with Sepigel 305.
CosChemFan

Member
April 9, 2015 at 10:01 pm

@Perry You mentioned that the CAPB should be formulated at a 5% “active base”. Most CAPB I’ve come across is only 30% active. So assuming that @cawarra has CAPB that is only 30% on an active basis he/she will only have 3.3% active material in the formula. And assuming he/she has a CAPB that is 50% active, 11% CAPB is 5.5% active material in the formula. Am I confused about how that works? I’m still a little fuzzy on this topic.

Regards,

CosChemFan
billichemist

Member
April 9, 2015 at 10:46 pm

@CosChemFan I understood it as the latter: i would have to use 10% of my 50% CAPB to get an overall 5% CAPB activity in the final formulation? is this correct?
billichemist

Member
April 10, 2015 at 3:43 am

i did a formulation as below

water - qs

glycerine - 5

ALS (26%) - 58

Adjust to pH 4.5

alcoholic extracts - 2

phenoxyethanol - 0.5

cocoamidopropyl betaine - 10

EO Blend 1

The EO is at 1% because clients wanted it to have a strong fragrance… Viscosity is beautiful when i add CAPB in and give like 3 stirs, but with subsequent stirring, the viscosity crashes out.. is there a reason for this/is this normal??
Venera

Member
April 10, 2015 at 4:58 am

It is. Your formula is no compatible with the fragrance formula.

You may have another way around. Get in touch with the fragrance house and ask them to adjust the fragrance formula to your formula. Most of them are very helpful. You can provide them with approximately 1kg base without fragrance, so they can have same material to work with.

Out of curiosity, have you tried Sepigel 305
OldPerry

Member
April 10, 2015 at 12:18 pm

You’ve got it. 11% of a 50% active ingredient is 5.5%
CosChemFan

Member
April 11, 2015 at 12:55 am

Thank you for responding! So @Perry I guess I’m looking for further clarification as to why you said cawarra’s formula had too much CAPB? Or were you making a general statement that the DEA + CAPB was too much? I just want to be sure I’m not over/under doing things over here in my formulas ).

Regards,

CosChemFan
OldPerry

Member
April 11, 2015 at 10:00 pm

Hello @CosChemFan - Sorry, I didn’t consider the % activity when I was answering. I believe the CAPB we worked with at Alberto was 100%. Although I could be remembering it wrong.
CosChemFan

Member
April 12, 2015 at 10:48 pm

Thank you @Perry!
billichemist

Member
April 13, 2015 at 5:02 am

@venera Thank you for that… unfortunately, ihave developed the fragerance ourselves based on the aroma alone and i have no expertise in fragrance compounds! i am not sure what i will do now. I have yet to use sepigel 305 as i am waiting for it to come in.

I tried thickening the above with salt but it seems the sample with the most ideal viscosity was the control (no salt) because i didn’t stir it much(the more i stir it, the thinner it gets, so when i try to dissolve the salt in by stirring, the product goes super thin)! i assume this high viscositywill crash out over time?
Bill_Toge

Member
April 13, 2015 at 7:06 am

this is the chemical structure of CAPB

at pH 4.5, the carboxylic acid group on the end is protonated, and no longer carries a negative charge, so the overall charge on the molecule is positive

the sudden increase in viscosity is because the positive charge on the CAPB is attracted to the negative charge on the ALS, and the two come together to form a transient insoluble “gel”, which breaks down when the CAPB is fully dispersed

try adding it at pH 7 instead of pH 4.5 and see if you get the same effect; I’ll bet you won’t

Page 1 of 2

1 2 →