chemicalmatt
Forum Replies Created
-
IF there is any U.S. university that conducts SPF testing, it would be one of the few that developed cosmetic science programs: Farleigh Dickenson in NJ, University of Cincinnati in OH, or University of Southern Mississippi in MS.
-
All beeswax has a residual odor, even refined, due to the free acid content. If it is too strong, then check the Acid Value of your source and look for a lower one.
-
That’s what I was thinking, Dr. Worthen. By “color change” haroon, do you mean “milky” (“like malik” as stated) ? At -3C (25F) a lot of formulations will cloud.
-
Try dipropylene glycol to offset the SDA. Used as a fragrance fixative too!
-
If you are in central North America I recommend Bria Research Labs in Libertyville, Illinois. [www.brialab.net] These folks are old hands at claims substantiation.
-
At such low water activity with 10% glycerin, your risk factor is extremely low. Having said that, the wetted bar becomes a factor for mold growth (bacteria not so much). In the good ‘ol days 0.10% propylparaben in there would do the trick well. Put it in there and don’t tell anyone?
-
That is a lot of GHPTC in there, twice what I would have used. You are correct in adding the amphoteric before any else, as that is the hydrotrope here. I’ll bet you need a LOT more of it or use a different one. Best one to use: disodium cocoapmphodipropionate (40% standard commercial). Works every time.
-
ITs the rice starch that is contributing to your rheology and skin conditioning more than the rice protein. No alkali needed. I like the “gruel” moniker. Rice flour can make for quite a thick roux when you cook with it, BTW. Ask any gluten-free chef.
-
Funny, every high active DDBSA I ever saw was dark as espresso coffee. The pure 96% acid will darken 304SS when contacting for more than a few hours, but a quick treatment with peracetic acid solution takes care of that. In practice, you always add the alkali to water first (after determination ala Belassi or Stepan lit) then slowly add the LABSA or DDBSA to the mixture until done. Cheapest way to make laundry detergent.
-
Gunther: I am skeptical about that 50% DM200 holding up for very long, with just 1.5% BTMC at work, I don’t care what Croda states. In your formula, you used volatile silicone, I see. That will evaporate once on the hair - you OK with that? Also, try using the smaller DMC polymer (200) rather than 350 and your spray pattern should improve a bit.
-
For “bush soap” - meaning a liquid that will clean your hands, utensils, dishes, clothes even, I’d blend together 5.0 - 10.0% sodium lauryl sulfate 98% powder (Stepanol WA-100) with sodium bicarbonate as base, ass 1.0% tetrasodium EDTA as anti-deposition aid, then call it soap when diluted 1: 20. This will dissolve in water far easier than those other solid-state surfactants mentioned.
-
The debate over conditioning effectiveness between these two polymers continues on…but my vote goes for low MW Polyquaternium-10 (aka Polymer JR-400) in shampoo/cleanser systems. Some folks hedge and use both. As for build-up, the cationic guar usually will build less, but that may depend upon what else you have with it, e.g. dimethicone.
-
NOT an emulsifier - as Belassi pointed out - but forms lamellar liquid crystal micelles WITH a primary emulsifier, which thicken your lotion or cream very efficiently.
-
No worries: employ a lactate buffer at pH 5 - 6. Urea will always slowly hydrolyze to biuret, ammonium nitrate and eventually ammonia, but that goes with the territory, as everyone knows. Urea creams are one of the oldest “natural” product formulations in existence - nearly 100 years of use. They work well too.
-
Kioko: cetrimonium chloride is a perfectly fine cationic emulsifier, you wont need to spend money on that behenyl quat. Assuming you are using the standard 30% active CETAC, increase this to 2.0%, then reverse the concentration ratio of cetyl alcohol: glyceryl stearate from 2:4 to 4:2. Should you need to thicken it, add sodium chloride (in solution!) incrementally, no more than 0.15% solid basis.
-
It is not heat sensitive for short periods of time, Lindsay. It WILL however make an endothermic reaction when it hydrolyzes with water, so I always used that physical property to my advantage when making urea creams: emulsify, then add urea during cool-down so it will help the process along. Cool, huh? (Yes, pun was intended)
-
Basic chemistry here, folks. Anionic organic salts and cationic organic salts (BTMS) do not play well together. Rid yourself of all the acids and the TEA, then you will be quite pleased with the result.
-
Spinr: drop the stearic acid if possible (unless you wish to add an alkali to saponify it), and sub with glyceryl stearate; glyceryl oleate might work even better, given the polar oil content. Not knowing the level of emulsifying wax, I couldn’t say how much, but 2.0% w/w would be a nice start. That is large oil phase you have there. Small amount of Steareth-2 (0.50%) would help stabilize also.
-
Kate, looks like you need another hydrotrope - or more of the one you have: CAPB. Neither SCI nor the glucoside is very hydrotropic and could use more help from the amphoteric, so raise that and lower the glucoside. The gel phase is likely either the hydroxypropyl guar, the glucoside, or a coacervate complex with the anionic, so drop the nonionic guar, keep the cationic guar and change your order of addition. Always add the amphotheric to your mixture after a cationic is added (HPGTC in this case), then the nonionic then anionic, so sequence: CAPB/glucoside/SCI. Also keep your pH above 7.0 since glucosides are less hydrophilic in the acid range and play well with others in the near alkaline range. Finally, drop the glycerine to an insignificant level and you will appreciate the higher viscosity and foaming. In surfactant systems such as yours, glycerine does absolutely nothing but kill viscosity, kill foam and rinse away to feed fishes.
-
Amit, don’t waste time using bentonite or other mineral clays. Kaolin does not suspend organic constituents, by the way, it just sits there. The best yield value is from guars or other saccharide gums (xanthan, sclerotium, etc,). You already have cationic guar in there - try upping it and co-dispersing it with hydroxymethylcellulose (“Methocel” by Dow) and the synergy may bring success. Good luck working with SeS. I’ve worked with it before - very toxic - take care there.
-
Hola’ Belassi. Long time/no blog. Urea compositions are best stabilized with lactic/lactate buffers at pH <6. The threshold of use for keratolysis is around 10%. At 40% you can dissolve the nail sheath if left on overnight. Cool, huh? uhhh…maybe not.
-
I’ll weigh in here - only because I must. Mary24: ignore all of the above. That 2.0% salt is hindering deposition of both re-fatting agents (Cetiol HE and Lamesoft, and Belassi is right you have too much.) I dare say the Polysorbate 80 isn’t helping either, so take both NaCl and Tween 80 out of there. Your viscosity will improve somewhat also when the Tween 80 is removed and the Lamesoft reduced. Employing a cationic polymer as suggested will likely be a waste of time and money, but try anyway just for kicks. Cationic deposition onto hair is dependent upon coacervation and your surfactant combo will not coacervate much at all. Everyone please read Des Goddard’s book. It will change your life. OK, maybe not your life, but at least your conditioning shampoo formulations.
-
Triglyceride oils used there? If so, heat to 65C add a little GMS then cool slowly back down to RT. If not, return to “GO”.
-
That is the easiest oil to emulsify, my friend. Try Emulsifying Wax NF (cetearyl alcohol and polysorbate 60), the most ubiquitous emulsion base used in HBA commerce. Next time try ask us something more difficult.
-
Thanks again, Bill Toge, for livening this blog with both his science and his wit. To enhance Bill’s insight: salts such as NaCl and Mg sulfate must be added to INVERSE PHASE emulsions (w/Si or w/o) to stabilize these just as Bill says, and also depending on the emulsifier type used. Adding a salt to a standard o/w emulsion is a good way to DESTABILIZE it. I found that 2.0% salt in the water phase of the appropriate w/o or w/Si emulsion does the trick nicely, even though suppliers (Evonik,others) usually state 1.0% or less. Technical tidbit of the day: this is exactly how the trendy HIP emulsions are made. Word.