[Gunther]

@chemnc I prefer to 
1 heat water to about 170 F (70 C)
2 pour BTMS
3 stir for 10+ minutes to make sure no mini clumps remain (you can draw a bit with a spoon and watch it under a magnifying glass)
4 for creams: add oils now
5 for conditioners: allow to cool off a bit and add silicones

I believe you can get away with single-pot mixing with BTMS
but I’d rather make sure all BTMS has properly melted and dispersed.

[Gunther]

@Sal you’d better do the extraction yourself.
Most extracts are badly watered down.

Use water to extract them. Heating or boiling may be needed.
Alcohol has no use in shampoo.

You can buy the powdered plants by mail.
Less troublesome at customs than mailing the whole plant.
Powder extracts are also less likely to be diluted.

[Gunther]

For some reason pH measurements in cosmestics don’t stick to what theory says.

i.e. grab any shampoo measure its pH, 
dilute 10x
measure pH again
it ain’t a whole pH point higher as theory said it would (it’s a bit less than that).

[Gunther]

Have you tried Oxiteno products?

They’re supposed to be widely available in Mexico and inexpensive. I believe they even have a factory there.

Oxiteno’ Alkont EL 3645 worked fine for me for thickening low sulfate + glucosides formulations.

[Gunther]

@Belassi would you mind enlightening us with a quick review of the thickening options available, please?

[Gunther]

Making semiopaque sunscreens with ZnO is tricky.
You’d be safer by buying a reputable, commercial product. They have been properly and thoroughly tested to be able to claim the SPF you see on the label.

If you don’t mind the totally opaque (white) look
you can try several recipes available online. They’re more forgiving to misformulation/mismanufacture for thick, opaque layers
you can try Titanium dioxide as well.

[Gunther]

IMO BTMS-50 is best poured when the other ingredients have warmed up already, to 170 F (70 C)
Pouring it cold leads to tiny clumps.
I don’t know why, and I never read that mentioned anywhere, but my experiments suggest so.

[Gunther]

No pic found
but these patents say
that in order to make DMDM hydantoin,
3,5 dimethyl hydrantoin reacts with paraformaldehyde (formaldehyde polymer)
so it makes sense to think that the reaction happens backwards too, to release formaldehyde.

https://patentimages.storage.googleapis.com/5a/d5/80/ec85964d82b9a9/US5037843.pdf

https://patentimages.storage.googleapis.com/56/27/b9/ae65c945e2f9e0/US5616722.pdf

[Gunther]

In Central America (Latin America), so I get the same (or worse) sourcing problems that @Belassi has.

[Gunther]

Update:

I tried a pretty similar formulation just switching the addition order as @chemicalmatt suggested in other posts.

60% deionized water
( this time no EDTA, no preservatives, just to see if they somehow interfere )
5% Polyquaternium-7
4% Dehyquart-A ( about 1% active Cetrimonium Chloride )
10% Dehyton-K ( 3% active CAPB )
Allowed to rest undisturbed for 45 minutes. Solution remains water-thin and crystal-clear.
10% BCare2000 ( about 5% active Decyl glucoside )
Allowed to rest for about 15 minutes.
0.5% SLS powder
6.43% Texapon N70 gel ( 4.5% active SLES )
( 5% total sulfates )
Left undisturbed overnight for Texapon to dissolve.

The next day, this formulation has a slightly viscous, crystal clear appearance.
Contrasting to the water-thin, slightly cloudy one mentioned above.
On adding citric acid (powder) little tiny bubbles were formed.

This one was much more conditioning than the previous one, just by switching the addition order.
Too bad I can’t seem to find Polyquaternium-10 locally.

Now I’ll try to add silicones
1 I’ll try adding some Amodimethicone+Cetrimonium+Trideceth blend, plus some extra CETAC to reach 1-2%.
2 I’ll see if BTMS-50 + dimethicone can hold in solution, with this new addition order.

[Gunther]

Some suggestions listed below:

1 Colloidal Silver (or pretty much any Silver compound) is unsafe for toothpaste or any other use where it can be ingested
https://nccih.nih.gov/health/silver
https://en.wikipedia.org/wiki/Argyria

2 I don’t see any emulsifier or at least surfactant that’s holding oils soluble.
IMO that’s the most likely cause of separation.

3 Depending on your definition of natural, you may add some small amounts of Potassium cocoate (coconut oil saponified with Potassium hydroxide) to give it some foaming, extra cleaning. It requires a bit high pH to remain stable.
While a bit high (alkaline) pH ain’t that troublesome in toothpaste (some contain Sodium bicarbonate to rise pH), don’t overdo it either as to avoid excessively high pH.

4 Calcium bicarbonate is much more water soluble than Calcium carbonate.
Thus less likely to precipitate out of solution.

5 Check to see if Erythritol has better anticaries action than xylitol.

6 You can choose essential oils that have the highest anticaries action according to studies (i.e. cinnamon oil if I’m not mistaken).

7 For a more “natural” approach you could use a little ethyl alcohol. 
Many commercial mouthwashes already have lots of it.

8 Other than that, you’d need synthetic preservants.

9 You can try an anhydrous (no water) formulation with coconut oil+gum to see if it works.
I believe studies show some anticaries activity from coco oil.
Anhydrous formulations can sometimes be formulated preservative free.

10 Please keep us updated with your results.

[Gunther]

Now I tried the following formula, but somehow it didn’t feel as conditioning as the one wihout glucosides but with PEG-7 Glyceryl cocoate.

50% deionized water
0.1% EDTA Na-4
0.4% Sodium Benzoate
5% Erythritol
1.5% SLS powder
5% Texapon N70 gel (3.5% active SLES) ( 5% total active sulfate surfactants )
(allow time for it to dissolve)
10% Bcare2000 (about 5% active Decyl Glucoside)
10% Dehyton K ( 3% active CAPB )
( at this point, mixture is crystal clear, almost water-thin )
5% Polyquaternium-7
( allow to rest for 2 hours )
(it remains crystal clear, slightly thicker )
2% Dehyquart A ( Cetrimonium Chloride )
( some cloudiness upon addition that later clears out, some viscosity builds, lots of tiny bubbles form despite gentle stirring )

I’d try upping Dehyquart to 5% to see if it’s any more conditioning.

I’ll also try cationics (PQ-7, CETAC) / CAPB / glucoside / anionics (sulfates) addition order as @chemicalmatt advised here
https://chemistscorner.com/cosmeticsciencetalk/discussion/comment/27942/#Comment_27942

[Gunther]

Thanks @Perry . When reading your replies I always keep on looking for the Like button.

Did you notice any worse performance in formulations without them?
Did you notice any sticky afterfeel from cocamide DEA at 1%+ ?

[Gunther]

You’ll need to check the testing method they use

These can help:
https://www.cptclabs.com/spf-testing-lab-guide/
http://www.princetonconsumer.com/spf-testing/

At the end, if you keep on getting different values
you’ll have to have different labels/packaging depending on where the product is sold.

[Gunther]

No problem @Belassi

In fact I’m thankful to you for posting them.
Teachersource looks great

Please keep us posted on how their Polyox works in personal care products.

Right now I’m still surfing their site for some projects for my daughter’s science fair (and some for me).

[Gunther]

Are there any EDTA derivatives, or any other substances that work just like EDTA
without bearing its name?

[Gunther]

Interesting

@chemicalmatt , what would happen with SCI/glucoside/CAPB/cationic addition order?
Is cationic/CAPB/glucoside/SCI order advised just because of solubility issues, or because nonionics (glucoside) somehow modify the cationic/CAPB mixture micelles?

Sorry if this sounds like a totally newbie question
but I’m just at the ‘anionics+cationic coacervates can be compatible and beneficial’ stage.

Review on Anionic/Cationic Surfactant Mixtures

Abstract

It is commonly known that cationic and anionic surfactants cannot be mixed without the risk of precipitation or instability. However, many studies have shown that not only is it possible to combine cationic and anionic surfactants, but also that this combination can present synergic properties. Mixtures of anionic and cationic surfactants have many unique properties that can be very useful when used properly. The aim of this report is to present relevant information concerning the interaction between anionic and cationic surfactants. A bibliographic review on anionic/cationic mixtures is presented here in order to better understand their properties and possible synergic effects, as this is of practical importance for the chemical industry.
https://link.springer.com/article/10.1007/s11743-007-1047-1

[Gunther]

I tried cold brewing coffee 
230 ml deionized water
150 mg SLS powder
mixture of finely and coarse ground coffee
and it gave a distinct reddish, brick like color.
The smell was nothing to write home about, but neither did hot brewing for that particular ground coffee.
I’ll try again with a more expensive, aromatic one, to see if it’s any better.

Interesting study on coffee oils:

Topical use and systemic action of green and roasted coffee oils and ground oils in a cutaneous incision model in rats (Rattus norvegicus albinus)

Abstract

Introduction

Wounds are a common health problem. Coffee is widely consumed and its oil contains essential fatty acids. We evaluated the local (skin) and systemic effects associated with the topical use of coffee oils in rats.

Methods

Punch skin wounds (6 mm) incisions were generated on the backs of 75 rats. Saline (SS), mineral oil (MO), green coffee oil (GCO), roasted coffee oil (RCO), green coffee ground oil (GCGO) or roasted coffee ground oil (RCGO) were topically applied to the wounds. Healing was evaluated by visual and histological/morphometric optical microscopy examination; second harmonics generation (SHG) microscopy, wound tissue q-PCR (values in fold-change) and blood serum (ELISA, values in pg/mL).

Results

RCO treated animals presented faster wound healing (0.986 vs. 0.422), higher mRNA expression of IGF-1 (2.78 vs. 1.00, p = 0.01), IL-6 (10.72 vs. 1.00, p = 0.001) and IL-23 (4.10 vs. 1.2, p = 0.05) in early stages of wound healing; higher IL-12 (3.32 vs. 1.00, p = 0.05) in the later stages; and lower serum levels of IFN-γ (11.97 vs. 196.45, p = 0.01). GCO treatment led to higher mRNA expression of IL-6 (day 2: 7.94 vs. 1.00, p = 0.001 and day 4: 6.90 vs. 1.00, p = 0.01) and IL-23 (7.93 vs. 1.20, p = 0.001) in the early stages. The RCO treatment also produced higher serum IFN-α levels throughout the experiment (day 2: 52.53 vs. 21.20; day 4: 46.98 vs.21.56; day 10: 83.61 vs. 25.69, p = 0.05) and lower levels of IL-4 (day 4: 0.9 vs.13.36, p = 0.01), adiponectin (day 10: 8,367.47 vs. 16,526.38, p = 0.001) and IFN-γ (day 4: 43.03 vs.196.45, p = 0.05). The SHG analysis showed a higher collagen density in the RCO and GCO treatments (p = 0.05).

Conclusion

Topical treatment with coffee oils led to systemic actions and faster wound healing in rats. Further studies should be performed are necessary to assess the safety of topical vegetal oil use for skin lesions.
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0188779

[Gunther]

@Perry I see that you posted

Most companies will not go over 2% since NaCl can sting the eyes. Your formula will also not necessarily get thicker by adding more salt.

https://chemistscorner.com/why-does-salt-thicken-shampoos/
(In the comments replies)

Did you notice any worsened performance or sensorials with 3%+ salt ?

Thanks in advance.

As an interesting comment, this Colgate-Palmolive patent says that Ammonium surfactants need less salt to thicken, but the curve is narrower (thus easier to inadvertently get past peak viscosity) than Sodium surfactants.
https://patents.google.com/patent/EP0574086A2/en

[Gunther]

Glucosides definitely move the salt curve to the right (and maybe lower peak viscosity as well)

 In the past, I’ve tried the following formula without any glucosides,
and it visibly thickened just by adding Coco-Betaine / CAPB, requiring 0.5-0.75% to achieve the desired viscosity.

Now just added 2% salt (in 0.25% increments) and still doesn’t reach proper viscosity.

50 % deionized water

0.1% EDTA Na-4

0.4% Sodium Benzoate

2.5% SLS powder

8.43% Texapon N70 gel ( 5.9% active SLES )

( SLS+SLES = 8.4% total sulfates )

10% Bcare2000 ( about 5% active Decyl Glucoside )

10% Dehyton K ( 3% active CAPB )

 While for now I left it resting undisturbed to allow for bubbles to dissipate,
I will add further salt beyond 2% and post results.

But the result is clear: glucosides move the salt curve to the right (and possibly lower peak viscosity too).

Maybe not entirely a bad thing. It may prove useful for conditioning shampoos containing anionics + cationics, which often form a viscous slime.

[Gunther]

Why do you want such an alkaline pH?

Let’s hope it’s for an industrial formula.
It will be too dangerous for household use.

You may get better foaming and stability using SLS.

[Gunther]

@Belassi would you mind posting the link for Teacher’s supply?
I couldn’t find it there. Search bar didn’t help either.

[Gunther]

Thanks @Perry  but wouldn’t it be be better to both

lower hair pH beyond what water rinsing can (for a smooth feeling hair)
and provide a quicker and more complete neutralization, as to avoid further hair damage?

[Gunther]

Does cold brew coffee has any better smell?

While higher temperatures improve solubility,

heat may degrade or evaporate some labile coffee chemicals

and they may precipitate out of solution when it cools off to room temperature.

Connoisseurs say you must wait at least 24 hours for a good cold brew coffee.

I think you can add some preservative to the water, and let it sit for several days.

I wonder if adding some surfactants to the water, yields a better coffee extraction.

 @Chemist77 unfortunately the Dow local distributor here mostly sells agricultural chemicals.

[Gunther]

Did you find rinse-off coffee products leaving a slightly sticky afterfeel?

I tried briefly rinsing my hands with unsweetened coffee, as you would with a hand wash, as slight tackiness was felt.

Where can you buy small quantities of suitable Polyox?
Even makingcosmerics sells it by the bucket
https://www.makingcosmetics.com/PEG-90m_p_848.html