[chemicalmatt]

Grip, you’re not going to like this:  the answer to your issue is none of the above.  All of those acrylate polymers, even the much vaunted Aqua SF-1 are electrolyte intolerant  - at the level you are working with, anyway. With a straight-up, low/no water soap system based on earth alkalis, your best bet is keep on with the colloids. I’d investigate Veegum, laponite, or good old bentonite even. You also have the disadvantage of using the scrub with the highest bulk density known: pumice.  That’s suspending rock, dude. Your soap may not look as pretty with the bentonite holding up your pumice, but then pumice ‘aint so pretty either, am I right? Then again, without much water to work with, I’m unsure you’ll be getting anywhere with anything. Good luck.

[chemicalmatt]

Bri, the author appears to be making a broad, somewhat pedantic statement about the incompatibility of benzoic acid with nonionics. They also state that caveat for other preservatives as well. They are not versed well in the science and the art of preservation. Lesson here: don’t believe everything you read, or at least apply critical thinking to it. They are likely referring to the deactivation of certain preservatives by TWEEN 60 and TWEEN 80. That applies to parabens, and somewhat to phenolics, but shouldn’t be deemed the same pathway for other preservatives, and certainly not other nonionic surfactant chemistries. Use PEG ethers and you won’t go wrong. As for quats, if you are talking straight alkyl/benzyl quat surfactants, such as CETAC, StearAC, etc., you might want to use something else than benzoic acid, and not much of it, since those compounds offer more antibacterial and antifungal activity than most realize. “Honeyquat”: they still make that crap??

[chemicalmatt]

Using straight coconut fatty acids with a very small amount of extra stearic, then saponifying at 80C, in order, with TEA, KOH and NaOH usually produces the best results. You’ll see on labels lauric, myristic, palmitic acids: those, along with stearic, comprise 85% of the coconut FA fraction.  You will get dramatically different physical state and foam state outcomes using TEA vs. NaOH vs. KOH alone, that’s why a combo of alkali are used, and order of addition important. Expect the product firmness and appearance to change over the first six months. The old Noxema - Calcium (oil soap) and Ammonia (water soluble) with stearic/palmitic used there - would gain a golden soft pearlescence after 4 - 5 years. With TEA now in decline, I’ve been wondering what the shave cream people are doing these days. TEA gives you the lush, pearlescent foam most consumers expect. Perhaps they are revisiting ammonia?

[chemicalmatt]

There are many, many more fragrance components stable in ammonia than there are stable in sodium hypochlorite, a stong oxidizer. You really need to run this by your fragrance supplier, else you will be at it a long time.

[chemicalmatt]

I’ve never used it, so I couldn’t say. Look into the Noveon urethane fixatives (now Lubrizol) for starters.

[chemicalmatt]

To Sarah: I realize you do have a full brain, so please excuse my ratty comment in the original post.  That you’ve used that Lonza Biovert with no difficulty is as much a testament to your good GMP as it is to your preservative selection.  I’ve read Lonza’s literature and I find it underwhelming. That product relies on redox processes, and it’s activity can be imperiled by so many ingredients, including ones mentioned or alluded to by Making and Mark. Regarding Mark’s comment,Sarah, have the results of your USP Preservative Challenge been acceptable, and did you retry that challenge on the same lot 12 months later? I’d be curious.

To all: thanks for the feedback.  You all make a compelling argument that a holistic approach to formulating must be employed when using any preservative that does not use blunt cell-disruption chemistry, like my friends the parabens, phenolics and formaldehyde donors do Regarding point #11 in Making’s exhaustive list: Dave Steinberg once said the best preservative of all is strict GMP.

There’s enough material here to draft an interesting article in C&T or SPC.  Anyone game?

[chemicalmatt]

…and I know what you’re already thinking: yes, they do stain one’s clothing. Big time.

[chemicalmatt]

You betcha’ there is. Have you considered the polyurethanes? 

[chemicalmatt]

Mark, I think those crystal sticks are just aluminum chloride, plus some Epsom salt, other stuff.  The “ammonium” tag is a red herring. Further evidence of the paucity of integrity among so many in the natural product industries. Just look at the price points: I rest my case.

[chemicalmatt]

Pepe, since this sounds like a typical alkali saponification formula, limit your emollient additives to the water phase. I’d suggest Polyquaternium-7, another acrylamide copolymer (see Merquats),  PEG-12 Dimethicone, PPG-5 Ceteth-20 (Ele’ Corporation’s - NOT Croda’s); all compatible with the anionic system to some degree. These will lend the slip without affecting the soap.

[chemicalmatt]

Thanks for the lead-in, milliachemist. It’s good to take a break from Ebola combat today.

To address nasrins’ immediate problem, perhaps she only needs to alter her order of addition.  If she has 15% total solids surfactant activity in her formula, the norm for a baby washer, and we assume most of that is amphoteric, also the norm for those products, then she likely has what she needs to clarify her formula.  She needs to incorporate the fragrance oil directly into the surfactant blend, then add to water (or water to it, as the case may be) and other ingredients. As for the viscosity crash: I suspect a big slug of nonylphenol ethoxylate is lurking in her fragrance. That surfactant is commonly used as a fragrance oil ingredient (disperser-soulbilizer) and is a notorious viscosity crasher in anionic-amphoteric systems. Bummer.  Nasrins, you may need another builder in there, or a rheology modifier (Methocel works). 

[chemicalmatt]

Hey Belassi:  thanks for all this background information. In this age of rampant MERS, perhaps TTO (melaleuca alternifolia) can make a comeback in the homeopathic realm as a topical germ killer.  xenon126, for the record, thymol, the active extract from thyme (oil), is a substituted phenol used for many decades (see Listerine.) Furthermore, perhaps your discussion may have originated when you may have seen lactic acid listed in an ingredient dec.  Be advised it was only there as an acidulant, not an antibacti device.

[chemicalmatt]

Nadia, you refer to hair swatches, not switches, for testing purposes no doubt.  All types can be procured at Jos. Lowenstein & Sons of Brooklyn, NYC., the venerable source for hair swatches and dyes.

[chemicalmatt]

Belassi, contact Siltech directly for their line of water-dispersible alkyl modified silicones - and save a lot of money.  That price sounds WAY too high. Should be more like $15 - $20/ kg. Stay off of Lubrizol’s analogs too, they are over-priced compared to Siltech’s. Siltech rocks!

[chemicalmatt]

ZInk, none of the above, with possible exception of magnesium aluminum silicate, are peroxide stable, and neither is sunflower oil.  Unsaturated carbon bonds do not like peroxygens (or, correction, yes they do, and a lot).  Ethoxylated linear alkyl alcohols work best, e.g. Steareth-2, Ceteareth-21, etc.

[chemicalmatt]

It is used here as a foam stabilizer.

[chemicalmatt]

Use 350 CST dimethicone for all-around use in skin care. 1000 CST can be better for detangling in hair-care, and is almost as easy to emulsify as 350. I never unerstood the need for 200.or lower.  As for volatile silicone, all will dilute dimethicone easily. D4 works best in hair-care due to its higher volatility, and is lower priced generally.  Most of the majors supply a D4/D5 blend for general use, and yes, they are all cyclomethicone, just different heterocycle ring sizes. 

[chemicalmatt]

There is no maximum use threshold for that material to my knowledge.  In fact, it is sold in solid state form (100%) commonly, though no drug claim is made.

[chemicalmatt]

Nope.  Buy and use the 99% and save money.

[chemicalmatt]

Bill Toge is on the right track there, BJ.  The entire mess here should be considered a plasticizer, with the exception of water and PVP. That goes for those other commercial formulas too. My opinion: trying to emulate the Hicks Transformation w/s pomades, such as this one, is wasting time, money and effort by adding ANY fixative resin, given the huge level of nonionics incorporated.  Just adjust the level of Ceteareth-25  to the point you can package it without seizing the pistons on your PD filler, then leave it at that. Minimize - or delete entirely - all the rest.  These are not emulsions, they are surfactant gel solutions.

[chemicalmatt]

I cannot remember the particulars of the last CIR statement on PEG-40 HCO, but I do know it has been GRAS since the 1930’s, when it was invented. In fact, that compound was the very first nonionic surfactant ever introduced into commerce if I remember correctly. I’d be much more concerned with those essential oils promoting irritation.

[chemicalmatt]

That sounds wierd, as if you overshot the salt curve in time delay fashion.  There must be another element to this basic shampoo formula you are leaving out. Can you elaborate?  Also, get rid of glycerine: sulfate-free systems are difficult enough to build viscosity without having that infamous viscosity (and foam) killer in the formula. Also, it lends zero re-fatting efficacy in virtually all formulas. Friends, don’t let friends use glycerine in their shampoos and body washes. 

[chemicalmatt]

Adding to Bill’s discussion, Gustavo, add the CaOH2 to the tank with the mixer off.  Dump the bags slowly (wearing half-mask respirator,safety goggles, etc.) into - or rather onto -  the water phase surface, shut the lid, turn the mixer on at a slow speed and don;t open the lid for at least 10 minutes.  If you add directly to the vortex or a fast agitated water phase, you will generate a calcium hydroxide cloud and if that happens you will piss off many people, including me, and I won’t even be there. Safety first!

[chemicalmatt]

I’ve never heard of consulting chemists obtaining royalty rights to a marketed product, even though Bob’s logic makes (some) rationale for it.  Usually, JCG, formulation work is one-and-done. Also, ethical formulation consultants (like yours truly and present company, I hope) will lend advice during pilot-batch scale-up production gratis over the phone. If the process instructions and release specs are explicit and rendered in cGMP format, even this should not be necessary.  Any trips to a manufacturing facility to follow up will require more fees and travel expenses of course. I’ll add my !!! to David’s too.  $25K for a single formula is pretty darn high.  That better be one helluva original formulation they provided you.

[chemicalmatt]

Bob’s right on this one.  Those things “seed” too early, they get grainy.  For the record, ozgirl, there is no issue with the raw material.  That Sylvaclear stuff will stay viable for years, if not decades!