As I hinted in this post, there is a property that surfactants have called critical micellization concentration (CMC). I did a bit of research on it when I was trying to find out how much surfactant is used in a micellar cleansing water (which is obviously a different amount for different surfactants)... it can't be "micellar" water unless there are micelles! If you don't know what a micelle is, go spend a few minutes at the University of Google, and meet me back here.
So, to simplify, the CMC is the lowest concentration of a surfactant that will form micelles in water (or whatever diluent the researcher is determining/stating the CMC for... we are really only concerned about water), so it is the lowest concentration of surfactant you need to be able to call your solution a micellar water!
These values didn't end up being super helpful in determining proper surfactant concentrations for micellar cleanser, since they are so low as to likely be inadequate for cleansing purposes, but they are interesting nonetheless and, by definition, form the lower limit for surfactant concentrations in a micellar cleanser.
The ones I have collected are for surfactants I own; if you know others you'd like to submit to this list, please comment with the values! CMCs are listed in various units including ppm (parts per million), mol/L (moles per litre), and g/L (grams per litre). I am listing in grams per litre of water, since that is most useful in cosmetic chemistry formulating, but if you are a nerd like me you can sort out how to convert from mol/L to g/L (that's how I got the value for decyl glucoside).
CMCs of various surfactants
1.7 g/L caprylyl/capryl glucoside
0.7 g/L decyl glucoside
0.06 g/L (60 mg/L) polysorbate-20
1.1 g/L PEG-40 hydrogenated castor oil
N.B. It is just my assumption, but I would think that the CMCs refer to concentrations of active chemicals in your surfactants, since they can come in different strengths. That is, you'd need 10 grams of a 10% active surfactant to get 1 gram of the actual surfactant ingredient into your formulation. The stuff as it comes out of the bottle is not 100% active; for example, the decyl glucoside I have is 51% active. Note that I write my formulas for "as it comes out of the bottle." So my decyl glucoside micellar water that was "1% decyl glucoside" actually only had 0.51% active decyl glucoside in it.
Showing posts with label surfactants. Show all posts
Showing posts with label surfactants. Show all posts
Tuesday, July 12, 2016
PEG-40 hydrogenated castor oil micellar water
I hadn't opened my container of PEG-40 hydrogenated castor oil (hereinafter referred to as PEG-40) yet, so I thought I'd give another micellar water a go using this as the surfactant. Given that I liked how my skin felt using the polysorbate-20 version (after rinsing off the nasty stinging Optiphen Plus), I was hopeful that I might like this one too; they are both non-foaming surfactants, usually used as solubilizers.
Following the formula of my last couple of batches, this one was just water, surfactant, and preservative. I switched out my 1% of Optiphen Plus and used 0.5% of liquid Germall Plus instead. This time I heated the water and PEG-40 together so the PEG-40 would melt; it's quite thick at room temperature. Once it cooled down, I added the preservative.
My opinion of this one is that it feels much nicer than the caprylyl/capryl glucoside and the decyl glucoside versions due to the lack of soapiness and not feeling crazy-dry after using it, and better than both of those and the polysorbate-20 version due to not having the Optiphen sting. I also think I like it better than my first Cromollient version because it's not as sticky, but I think that is the fault of the glycerin in that recipe.
My skin felt clean-ish and fresh after using this recipe. Bear in mind that I don't wear makeup, but I do use a prescription lotion and a sunscreen, as well as having really oily skin, which is what the cleanser was having to deal with after a full day at work. I don't know if I'll ever really be able to get behind a leave-on cleanser (I'm totally neurotic about rinsing toothpaste out of my mouth too), but it will be a convenient thing to have when camping or working outside in the summer, which is something I do fairly regularly.
Of all the recipes I've tried, this is my favourite so far, but I definitely want to give a fair chance to the Cromollient and polysorbate-20 by trying them in recipes without stuff that me and my skin don't like.
Following the formula of my last couple of batches, this one was just water, surfactant, and preservative. I switched out my 1% of Optiphen Plus and used 0.5% of liquid Germall Plus instead. This time I heated the water and PEG-40 together so the PEG-40 would melt; it's quite thick at room temperature. Once it cooled down, I added the preservative.
My opinion of this one is that it feels much nicer than the caprylyl/capryl glucoside and the decyl glucoside versions due to the lack of soapiness and not feeling crazy-dry after using it, and better than both of those and the polysorbate-20 version due to not having the Optiphen sting. I also think I like it better than my first Cromollient version because it's not as sticky, but I think that is the fault of the glycerin in that recipe.
My skin felt clean-ish and fresh after using this recipe. Bear in mind that I don't wear makeup, but I do use a prescription lotion and a sunscreen, as well as having really oily skin, which is what the cleanser was having to deal with after a full day at work. I don't know if I'll ever really be able to get behind a leave-on cleanser (I'm totally neurotic about rinsing toothpaste out of my mouth too), but it will be a convenient thing to have when camping or working outside in the summer, which is something I do fairly regularly.
Of all the recipes I've tried, this is my favourite so far, but I definitely want to give a fair chance to the Cromollient and polysorbate-20 by trying them in recipes without stuff that me and my skin don't like.
Polysorbate-20 micellar water
After the unwanted foaminess with the caprylyl/capryl glucoside and decyl glucoside attempts, I decided to change course and go for a definitely-non-foaming surfactant, polysorbate-20.
I followed the same strategy and processing as in the decyl glucoside formula, with just water, surfactant, and preservative, at the same percentages.
I couldn't believe it when this one stung too! Polysorbate-20 is recommended at up to 20% of a formula (and is mostly used for leave-on products)! That's when I figured out it wasn't likely the surfactants stinging... it was the Optiphen. Looks like my skin prefers parabens and formaldehyde donors... on my face, anyway. Oh well, I'm not afraid of well-tested ingredients. I also feel like powdered Germall Plus is on its way to becoming my favourite preservative anyway; it's so much cheaper and you use so little of it!
My skin felt good after using this formula (after rinsing it off to stop the Optiphen sting), not crunchy like with the last one. So, I'll be trying this one again some time with a different preservative.
I followed the same strategy and processing as in the decyl glucoside formula, with just water, surfactant, and preservative, at the same percentages.
I couldn't believe it when this one stung too! Polysorbate-20 is recommended at up to 20% of a formula (and is mostly used for leave-on products)! That's when I figured out it wasn't likely the surfactants stinging... it was the Optiphen. Looks like my skin prefers parabens and formaldehyde donors... on my face, anyway. Oh well, I'm not afraid of well-tested ingredients. I also feel like powdered Germall Plus is on its way to becoming my favourite preservative anyway; it's so much cheaper and you use so little of it!
My skin felt good after using this formula (after rinsing it off to stop the Optiphen sting), not crunchy like with the last one. So, I'll be trying this one again some time with a different preservative.
Decyl glucoside micellar water
I have learned to start simple now. At least after two semi-fails.
Next surfactant on the to-try list is decyl glucoside. After the stinging I experienced with the caprylyl/capryl glucoside recipe, I stripped this one down to three ingredients: water, surfactant, and preservative. Just distilled water, 1% decyl glucoside, and Optiphen Plus.
Boiled the water, added the surfactant, cooled, added preservative, and mixed.
It foamed and stung when I used it. Boo. I had to rinse my skin after applying this, and it felt stripped, as though I had used a strong-ish rinse-off cleanser. That decyl glucoside is powerful stuff.
At this point I still hadn't put two and two together regarding the Optiphen stinging, I was too taken aback by all the foam!
Next surfactant on the to-try list is decyl glucoside. After the stinging I experienced with the caprylyl/capryl glucoside recipe, I stripped this one down to three ingredients: water, surfactant, and preservative. Just distilled water, 1% decyl glucoside, and Optiphen Plus.
Boiled the water, added the surfactant, cooled, added preservative, and mixed.
It foamed and stung when I used it. Boo. I had to rinse my skin after applying this, and it felt stripped, as though I had used a strong-ish rinse-off cleanser. That decyl glucoside is powerful stuff.
At this point I still hadn't put two and two together regarding the Optiphen stinging, I was too taken aback by all the foam!
Caprylyl/capryl glucoside micellar water
Given that I have a camping trip coming up in a few weeks, and that I am neurotic about twice-daily face washing, I figured I should design myself some nice micellar cleansing water so that I only have to make the trek to the shower station once a day...
You might have already read about my previous micellar water experiment, but I felt like it was kinda sticky, probably from the few percent of glycerin I put in it, so I wanted to improve my recipe.
I also have several surfactants to try, so I think I will have a little series of micellar water posts. This one will be using caprylyl/capryl glucoside as the surfactant.
I still haven't learned to start simple, as you will see in this post.
Micellar water, as the name implies, is mostly water, with some surfactant added in at a sufficient concentration to form micelles. That "sufficient concentration" I refer to is different for each surfactant, and in chemistry is referred to as the critical micellization concentration, or the CMC. More on that in a later post. Micellar waters also contain things to make them nice for your skin, and also preservative(s) so they don't start looking like kombucha and/or give you a nasty infection.
The recipe I invented this time included water with 1% caprylyl/capryl glucoside and 1% or less of the following: hydrolyzed oats (general niceness), allantoin (occlusive), propylene glycol (dirt solvent/moisturizer), xylitol (for slip), lactic acid (exfoliation), and Optiphen Plus (preservative).
I pre-boiled the distilled water, and mixed everything together, and that was it.
It was waaay sudsier than I expected, including foaming up a bit on the cotton pad and on the skin when used. Perhaps my surfactant concentration is too high, as this is way too foamy and feels too much like a rinse-off cleanser.
Also it stings when I use it. Initially I thought that was from the lactic acid, but given that I can use 10% lactic acid gel with less stinging, I was suspicious. Upon further experimentation, I believe my face is sensitive to the Optiphen.
You might have already read about my previous micellar water experiment, but I felt like it was kinda sticky, probably from the few percent of glycerin I put in it, so I wanted to improve my recipe.
I also have several surfactants to try, so I think I will have a little series of micellar water posts. This one will be using caprylyl/capryl glucoside as the surfactant.
I still haven't learned to start simple, as you will see in this post.
Micellar water, as the name implies, is mostly water, with some surfactant added in at a sufficient concentration to form micelles. That "sufficient concentration" I refer to is different for each surfactant, and in chemistry is referred to as the critical micellization concentration, or the CMC. More on that in a later post. Micellar waters also contain things to make them nice for your skin, and also preservative(s) so they don't start looking like kombucha and/or give you a nasty infection.
The recipe I invented this time included water with 1% caprylyl/capryl glucoside and 1% or less of the following: hydrolyzed oats (general niceness), allantoin (occlusive), propylene glycol (dirt solvent/moisturizer), xylitol (for slip), lactic acid (exfoliation), and Optiphen Plus (preservative).
I pre-boiled the distilled water, and mixed everything together, and that was it.
It was waaay sudsier than I expected, including foaming up a bit on the cotton pad and on the skin when used. Perhaps my surfactant concentration is too high, as this is way too foamy and feels too much like a rinse-off cleanser.
Also it stings when I use it. Initially I thought that was from the lactic acid, but given that I can use 10% lactic acid gel with less stinging, I was suspicious. Upon further experimentation, I believe my face is sensitive to the Optiphen.
Sunday, July 10, 2016
surfactants in micellar water
Here's a link to an interesting article on surfactants, with a section on surfactants used in micellar cleansing waters. It gives some idea about types of surfactants used, and the usage rates.
Monday, June 20, 2016
Man wash
My dad loves Method's green tea and aloe fragrance (this stuff in particular). So I thought I'd try to make him a green tea scented all-in-one wash, since I know for a fact he regularly uses shampoo as body wash. My husband decided he wanted some too, but in a different flavour, so I made a biggish batch and split it in half before scenting it.
This one was an adventure in surfactants. I figured I'd use cocamidopropyl betaine because I use it in all my surfactanty things, and sodium laureth sulfate because it's a popular one, and because my formulating idol, Susan, usually uses three surfactants in any given product, I thought I'd add the only other one I currently possess, decyl glucoside.
Now, I know about decyl glucoside, and how hard it is to thicken, but I thought that because 2/3 of the surfactants were not decyl glucoside that I'd still be able to thicken it with salt. Wrong! So wrong!
When I'd mixed up all my ingredients it was about as thick as water. I tried adding 3% salt. No dice. "Xanthan gum!" I thought, "that's a thickener!" I added about a gram before bothering to look it up, only to find that it's incompatible with cationics, like the honeyquat I had also included. Then I got desperate. I found some gum arabic I had from a candy-making experiment a bunch of years ago and got that out. I swear to Dog, I added about 30 grams of it, along with some additional preservative to compensate. Now it is whitish, minutely thicker than it was before, and separates when left to sit into sections with and without floaty particles of organic gums.
Oh well, it foams. I scented it up and gave it to the guys with a bath pouf each. Are we counting fails? What number is this now?
I don't know what I'm going to do with the half-litre of decyl glucoside I have. I'm not the hugest fan of the foamer bottles, but I may have to adapt in order to use this stuff up.
This one was an adventure in surfactants. I figured I'd use cocamidopropyl betaine because I use it in all my surfactanty things, and sodium laureth sulfate because it's a popular one, and because my formulating idol, Susan, usually uses three surfactants in any given product, I thought I'd add the only other one I currently possess, decyl glucoside.
Now, I know about decyl glucoside, and how hard it is to thicken, but I thought that because 2/3 of the surfactants were not decyl glucoside that I'd still be able to thicken it with salt. Wrong! So wrong!
When I'd mixed up all my ingredients it was about as thick as water. I tried adding 3% salt. No dice. "Xanthan gum!" I thought, "that's a thickener!" I added about a gram before bothering to look it up, only to find that it's incompatible with cationics, like the honeyquat I had also included. Then I got desperate. I found some gum arabic I had from a candy-making experiment a bunch of years ago and got that out. I swear to Dog, I added about 30 grams of it, along with some additional preservative to compensate. Now it is whitish, minutely thicker than it was before, and separates when left to sit into sections with and without floaty particles of organic gums.
Oh well, it foams. I scented it up and gave it to the guys with a bath pouf each. Are we counting fails? What number is this now?
I don't know what I'm going to do with the half-litre of decyl glucoside I have. I'm not the hugest fan of the foamer bottles, but I may have to adapt in order to use this stuff up.
Friday, June 17, 2016
Shampoo!
After my entirely lacklustre (pun sort of intended :P) first shampoo and relatively smashing success at conditioner, it seemed like the shampoo needed another go.
I stripped it right down and put in a fair bit more surfactants than last time. My water phase included just-boiled water (as I wasn't double boilering this time due to not including the solid glycol distearate), cocamidopropyl betaine, sodium laureth sulfate, and glycerin, and my cool-down phase included preservative, fragrance, and a touch of dimethicone. Once these were all mixed and cooled, I added 3% salt to thicken.
It worked! It was thick, maybe a touch too thick, but it produced okay lather and was much more like shampoo than the last one!
Personally, I think I will be adding still greater amounts of surfactants; what can I say, I have greasy hair and I like the feel of surfactants on it! Despite it being a somewhat-less-mild surfactant (and despite the opinions of the granola crowd and the uninformed, who think it is the devil), I really like the feel of sodium lauryl sulfate in my shampoos. I might buy some if I can ever find a supplier, preferably in Canada.
I don't always say it, but I always test the pH of my products and adjust if needed. I like to keep my products (especially leave-on products) at pH 4-5. The skin and hair are naturally acidic, and acidic products disrupt them less than alkaline ones. Also, having a more acidic pH means many preservatives will be more effective, especially the more so-called "natural" (can't say I get how they are natural), food-grade ones like sodium benzoate and potassium sorbate.
I stripped it right down and put in a fair bit more surfactants than last time. My water phase included just-boiled water (as I wasn't double boilering this time due to not including the solid glycol distearate), cocamidopropyl betaine, sodium laureth sulfate, and glycerin, and my cool-down phase included preservative, fragrance, and a touch of dimethicone. Once these were all mixed and cooled, I added 3% salt to thicken.
It worked! It was thick, maybe a touch too thick, but it produced okay lather and was much more like shampoo than the last one!
Personally, I think I will be adding still greater amounts of surfactants; what can I say, I have greasy hair and I like the feel of surfactants on it! Despite it being a somewhat-less-mild surfactant (and despite the opinions of the granola crowd and the uninformed, who think it is the devil), I really like the feel of sodium lauryl sulfate in my shampoos. I might buy some if I can ever find a supplier, preferably in Canada.
I don't always say it, but I always test the pH of my products and adjust if needed. I like to keep my products (especially leave-on products) at pH 4-5. The skin and hair are naturally acidic, and acidic products disrupt them less than alkaline ones. Also, having a more acidic pH means many preservatives will be more effective, especially the more so-called "natural" (can't say I get how they are natural), food-grade ones like sodium benzoate and potassium sorbate.
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