

RobertG
Forum Replies Created
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RobertG
MemberApril 20, 2016 at 10:22 pm in reply to: FTC cracks down on misleading “natural” claimsUnless they adopt either a regulatory or judicial definition of “natural”, there cannot be due process of law in a “crackdown”. “I don’t know what the speed limit is, but you were over it”?
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As I look at how the ingredient quantities were stated, I want to ask, did you obtain SLES as a solid? I don’t know of any commercial sources of it that come that way, but only as approx. 30% in water or 60-70% in water-alcohol. Obviously saying “100g” means nothing if it comes only as solutions.
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I’d be very careful mixing persulfates with a fuel such as sodium stearate in a dry state. With the ammonium sulfate in there, even traces of transition metals could sensitize the mixture. The friction of a kitchen blender could be enough to ignite it, not to mention the possibility of a dust of it reaching the motor housing, where electric sparks could occur.
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Plus, the C8 (caprylic) is antimicrobial.
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That’s interesting, because of the lengths some formulators go to to make such a product feel like nothing!
I take it that glycol stearate is the monostearate, i.e. half ester. Maybe if you switched to the distearate it would feel waxier, and would continue to feel waxy as the arm rubbed against the shoulder all day. That or just increasing the amount of monostearate.
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I don’t have any knowledge of magnesium hydroxide as antiperspirant, but it could be used to buffer the alum. I do have experience using alum (both potassium & ammonium) in antiperspirants on myself. Alum has long use in such a role, but is irritating on its own. It can be made milder, but also less effective, by buffering it with alkali. Different people have different susceptibility to irritation by aluminum salts, and for some people the pH you’d have to get up to to make it no longer irritating would make it completely ineffective as antiperspirant. Some people can tolerate alum solution unbuffered. It has to be somewhat acidic to work at all.
Increasing pH also decreases its water solubility. Water-insoluble complexes of aluminum can be delivered as suspended powders or in some non-aqueous vehicle. I buffered alum with sodium bicarbonate in water, and shook it immediately before spraying on the armpit from a nose spray bottle; it did tend to clog, though.
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But the question wasn’t just about fingers inoculating the jar with microbes. The question is, could fingers bring in enough water to make, even locally on top of the rest of the product, the preservative too dilute to work?
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1.5% isopropanol in shampoo won’t reduce foam once it’s diluted in use, but it may be of slight help killing the foam while you’re mixing the ingredients, which is a good thing; probably not enough to help w that, though. Plenty of liquid shampoos, including tincture of green soap, used to have a lot more alcohol than that, although the foam-depressing effect of isopropyl is a little greater than of ethyl.
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How high performance does this solution have to be? Years ago I was consulting for a professional stage bubble blower who specializes in blowing them from his hands, but there are all sorts of desiderata you could try to maximize, such as number of bubbles from a single dip of the wand, resilience of bubbles, their weight or lightness, etc. Like Belassi’s idea, the high-performing ones tend to include a carbohydrate-based polymeric film-forming substance. Hydroxyethylcellulose is in common use.
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There are a lot of saponification catalysts that might be used to compensate for slowing the reaction by dilution. Mostly I hear about those as a result of cold kettle process soapmakers complaining that it happens too fast for their convenience with various fragrance additives. Ethyl alcohol will both catalyze the reaction and thin the product, but you may not want that in the final product.
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RobertG
MemberJanuary 11, 2016 at 4:43 pm in reply to: Best natural surfactant? Should I make my own or buy base?Since the “large bubbles” issue was raised by braveheart in a thread sainthil started about making shampoo, I’ll ask, do you mean large bubbles in shampoo? If so, why?
Large bubbles don’t seem to be any advantage in shampooing. Hair tends to break large bubbles down into fine lather, anyway. Ingredients commonly used to stabilize foams in, for instance, bubble bath are unnecessary in shampoo. Any tendency a solution has to foam is going to be brought out in the process of washing hair, so every surfactant is going to seem more lathery in shampoo than in other uses. Some of the ingredients that function as foam stabilizers in liquid shampoos are actually there to make the solution more viscous coming from the bottle.
As far as making your own surfactants, as Bob & Perry said, the economies of scale for all but the easiest surfactant synthesis (soap) so favor the big mfrs. that very few makers of finished products synthesize their own. (Even Procter & Gamble has for several years farmed out the making of Ivory soap to a company that specializes in running their old plant! I don’t know if this contractor makes the rest of their soap stocks and/or other surfactants too.) So if you’re interested in making $, buy from them; if you’re interested in recreational chemistry, prepare to do something more complicated than making soap or even biodiesel.
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If it’s like Stripe toothpaste, discharging from the neck of a tube, then it’s done by filling 2 tubes that are then laid side by side to dispense thru a neck with a septum.
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Could someone please explain to me the purpose of vacuum conditions for mixing? I can think of only 3 reasons one might apply vacuum during processing. 1 reason would be a slight negative pressure to keep out airborne contaminants. Another reason would be to degas one or more ingredients before mixing; degasing during mixing would seem to increase foaming. The last reason would be to remove a gaseous or volatile byproduct. Are there other reasons I’m missing?
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If minimizing eye sting is not a concern, one avenue you might take would be liquid or cream soap. By using a mixture of potassium & sodium soaps, you can get a creamy liquid consistency; all-potassium soaps will be clear, runny liquids, and the more sodium you add, the more opaque & viscous it becomes.
Preserving liquid soaps is a tricky & somewhat controversial matter. They aren’t alkaline enough to self-preserve against all plausible inoculums of bacteria, yet they are alkaline enough to curtail the action of many antimicrobials. There’s a thread on the problem here -https://chemistscorner.com/cosmeticsciencetalk/discussion/214/preservative-for-liquid-soap-done-with-koh — with a link (that still works) to an info resource. One tip that many agree on is that EDTA is of especially good help in preserving liquid soap; you might think soap itself would sop up the cations that bacteria crave as micronutrients, but apparently their affinity is low enough that EDTA helps a lot.
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It’s hard to generalize a lot of the things you asked about. For instance, nonionic surfactants encompass classes with vastly different hydrophilic groups, and that act very differently from each other & are typically used for different purposes. Some nonionics are used as foam stabilizers that make hardly any foam on their own, while others are foaming ingredients that have practically no foam stabilizing property. Other nonionics are more like foam moderators, producing some foam on their own but destabilizing the foam produced by other film-forming substances. Betaines have both foaming & foam stabilizing properties.
How betaines thicken is a combination of effects. Betaine surfactants are supplied in solutions with considerable amounts of simple salts, typically sodium chloride, and you can also buy low-salt versions; that salt has to be taken into consider’n in the total ionic strength of the solution as affects the viscosity of surfactants in it. The alkamidopropyl betaines also jell more or less with surfactants containing ethoxylated moieties. Betaines also have strong buffering capacity around the pH many preparations are adjusted to, so if you want to vary the pH you may find yourself needing more acid or base than you might otherwise, and therefore increasing ionic strength.
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RobertG
MemberDecember 25, 2015 at 12:50 am in reply to: Organic surfactant compatible with low pH (3.5)?Is it to be rinsed off?
If it doesn’t foam, you have only a few remaining options to apply & remove it. It can have a cream consistency, applied thick & rinsed or wiped off. Or it can be soaked into a matrix like a cloth that both dispenses it & soaks it back up, akin to damp mopping. Non-foaming preparations are hardly ever used for cleaning parts of the body other than hands & face; an example was the microwaveable detergent-emollient-soaked sponges I used from Rite Aid when I had to keep my feet dry following surgery.
Why does its pH need to be that low? Is it because acid needs to activate some ingredient of it that does something?
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RobertG
MemberDecember 23, 2015 at 11:10 pm in reply to: Journalist looking for experts on fermented cosmetic productsI don’t suppose you mean to include products containing lactic acid, or incorporating yogurt as a source of lactic acid. Or incorporating ethyl alcohol, for that matter! Because I guess those examples would be considered trivial because they’re commonplace.
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I know practically nothing about furoate esters. I’m guessing, from the Wikipedia entry that says 2-furoic acid is bactericidal & fungicidal, that the fatty esters are ways of either delivering that active material slowly in a sustained manner or of allowing it to penetrate oily media & membranes. Can anyone give me any info or point me to where I can learn about them?
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Since glycerol isn’t a sugar but a sugar alcohol, it can’t be fermented, which means the organism using it for food must obtain oxygen. Note that the fungus was on the surface, where it not only doesn’t feel the full osmotic pressure of the glycerol, but also could get oxygen from air. The better you can exclude oxygen from your container, the easier it’ll be to preserve. You might even be able to preserve the solution with a reducing agent such as a sulfite.
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I use this stuff, basically to use it up, since I haven’t been successful in marketing it — http://users.bestweb.net/~robgood/lather.html . When I was experimenting on the formula, I took a lot of baths, as well as putting solutions in my ears & up my nose!
However, for washing myself I usually use Ivory soap or even cheaper stuff such as Silk brand from Abu Dhabi, because I find solid soap more convenient, even for hair washing. If I move to where the water is “harder”, I might switch.
I have used samples colleagues wanted me to test or which were promotional, but I only use products of a general kind that I’d use anyway. However, when I was trying to sell my foaming formula for use in foam dancing, I did try foam dancing at the Palladium night club with the material they were already using.
I use all my homemade fireworks, because I wouldn’t let them out of my sight, although I did have other people light them in my presence when I was somewhat disabled from plantar wart surgery.
I used cis-4-methylaminorex obtained by a friend (who was promoting it as U4Euh), and wound up getting a patent on its method of use as a sinus decongestant. I also used gamma-butyrolactone that a friend was using to make Na GHB, and found that it’s actually better as a liquor substitute (in water tastes like bourbon, feels like booze w/o some of the latter’s adverse effects) in cyclic form than saponified. I was also among the first people outside General Foods to try their aspartame-sweetened Kool Aid, which may have been the first commercial use of NutraSweet, when Tom Borelli brought some into our class & we made it up in a volumetric flask.
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RobertG
MemberDecember 22, 2015 at 4:05 am in reply to: Simple but effective scale remover and cleanerThe phosphate problem is very much dose-dependent — that’s the dose coming from all sources, not just one person’s pipes! When phosphate salts were used in large amounts in laundry detergents, their contribution to phosphate in sewage & from other water sources in some places into some waters was significant. However, a specialized product such as a phosphoric acid based scale remover is used in such small amounts draining into a single sewage plant that it wouldn’t make a significant contribution. You could say the same of bath salts or food additives containing phosphates — they’re insignificant sources compared to urine.
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RobertG
MemberDecember 22, 2015 at 3:33 am in reply to: Organic surfactant compatible with low pH (3.5)?What sort of thing are you looking to clean with it, and how is the cleaning to be done?
Whether the surfactants are considered “organic” depends on the farming techniques used to grow the materials used to make them.
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Either outcome is possible.
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They’d better get this straight, because both materials are used in toiletries, so the context isn’t going to tell you one or the other.
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Bob. I suggest naming everything Bob.