Sunday, January 2, 2011

Iron Chemist: Sodium cocoyl isethionate (SCI)

Welcome to Workshop Stadium. This week the Chairman, Raymond (my lovely husband), has chosen the second Iron Chemist ingredient - sodium cocoyl isethionate. 

Here are the rules. Every week I will ask my husband to choose a number between 1 and 10. These represent boxes of supplies in my workshop. Once he has chosen a number, he will choose an item randomly from the box and I must make 2 - possibly 3 - products that include that ingredient. I will post the ingredient on Sunday and the products I've made out of said ingredient on Saturday along with the recipes. (If you wish to play along, you aren't limited to the same time frame and you don't need to make 2 or 3 products.) The only exception will be preservatives - I use them in everything anyway, and it won't end up being a very interesting product!

Unlike Iron Chef, you don't have to make the featured ingredient the main ingredient because we don't want to use our ingredients at unsafe levels.

As a note, we've changed the way Raymond chooses boxes. Since I've added a new box, there are a total of 10. So he will roll a 10 sided die and then choose from that box. Since he has very little concept of what each box holds, he'll choose something randomly. We switched to this method because most people aren't likely to choose 1 or 10 when asked to choose a number between 1 and 10, and we thought every box deserved a fighting chance! 

So what is SCI? Only my favourite surfactant ever! Here's a quick summary about this surfactant (for the entire post, click here).

Isethionates are considered exceptionally mild for skin, hair, and eyes, and are particularly tolerant to hard water. They leave behind a great skin feel - usually described as "silky" - and create really lovely foam, bubbles, and lather. SCI is great for every skin or hair type. The dry type will enjoy the gentle cleansing and the creamy after feel. The oily type will enjoy these features as well. SCI is great for a cream cleanser - the oils won't mess with the lather too much - and body washes. The down side is that SCI will make it difficult to make a clear shampoo, body wash, shampoo, or facial cleanser if you use the one with stearic acid.

The one Raymond has chosen is Jordapon prilled, which does not contain stearic acid.

So join me next Saturday to see the two or three products I make with this ingredient! As with last week, this is an ingredient I love and use in tons of different products - body washes, liquid shampoos, solid shampoos, hand cleansers - so it's going to be an interesting week as I try to figure out what to make!


Nancy Liedel said...

I almost peed my pants when I saw that picture. I was laughing so hard. I love my sci. Can't make a bubble bar without it and I make a darn fine bubble bar, if I do say so myself.

Anonymous said...

SCI is a wonderful ingredient and your right it is hard to make clear systems with it. A new ingredient / derivative of SCI is now available, ISELUX, which makes it really easy to make clear systems while maintaining all the benefits that SCI brings to the table. ISELUX is Sodium Lauroyl Methyl Isethionate. The added Methyl group makes it a liquid instead of a solid.

Robert said...

Where does the methyl go? Its maker characterizes the product as a "secondary ester", which I imagine means the methyl group is on the carbon alpha to the hydroxyl on the isethionate group -- i.e. that it's an ester of a secondary alcohol -- but I can't rule out (though I consider unlikely) the possibility that they mean it's a secondary acid ester, i.e. that they're using a methylated lauric acid.

One way to clear it up would be to look at the spec sheet of the product. If it contains methyl isethionate as a "leftover", that would answer that. Usually these acyl isethionate products contain an excess of isethionate, because the esterif'n rxn is easily reversible and they want to avoid an excess of fatty acid. OTOH in the prod'n of a product like Dove/Caress, an excess of fatty acid is used.

Bob Goodman said...

I got my answer at . It's the isethionate group, and going by the probably most economic method of starting with propylene oxide, the methyl winds up at a mixture of positions 1 & 2.

Anonymous said...

The methyl is indeed on the carbon alpha to the hydroxyl group. However, the methyl group doesn't make this surfactant a liquid instead of a solid. It in fact is a solid until it is formulated into personal care products. The methyl group allows it to be formulated into liquid cleaners whereas SCI can only be formulated into solid soap bars. The additional methyl group also increases foaming and increases skin compatibility in comparison to SCI.

Anonymous said...

......But I suppose it could be a methylated fatty acid or like you said a mixture on carbons alpha and beta. Makes more sense. Wherever it is - it doesn't half make loadsa loadsa loadsa BUBBLES. SHINEY SHINEY BUBBLES OOOOOOOOOOOOO.

DimeDesigns10 said...

how do i make a shampoo with the sodium cocoyl isethionate without getting all the clumping?