Tuesday, May 3, 2011

A few notes on SCI (sodium cocoyl isethionate)

I love love love SCI! If I could choose only one surfactant for the rest of my life, it would be SCI! (Click here for more information on this surfactant.) I use it in shampoo bars, body washes, facial cleansers, and everything else that might benefit from a creamy feeling lather and extreme mildness. So I need to clarify something...

All SCI contains some fatty acids that are left over from the coconut fatty acids used to create them. Some have more, some have less, but they all have a bit of fatty acid left in the process. This fatty acid helps increase mildness in our products and might be a reason that it feels so lovely on our skin. Are these fatty acids stearic acid? Possibly. Coconut oil doesn't contain a lot of stearic acid - it's mostly lauric acid, which has a great affinity for hair, and myristic acid, with a titch of the other acids thrown in for fun! - but we could find any of the fatty acids found in coconut in the end product of SCI.

Some SCI has an INCI of sodium cocoyl isethionate and some has an INCI of sodium cocoyl isethionate (and) stearic acid. This means stearic acid has been added to the mix to make it more noodle-y or flake-y. But all SCI contains some free fatty acids in the mix left over from the process of turning coconut oil into a surfactant.

For instance, Jordapon CI prill contains less than 6% fatty acids (INCI sodium cocoyl isethionate). Geropon by Rhodia contains 60% actives, less than 10% coconut acid, and more than 25% stearic acid (INCI sodium cocoyl isethionate (and) stearic acid). Tauranot 1-78 contains 10% to 12% free fatty acids and is 80% to 82% active (INCI sodium cocoyl isethionate). And Elfan by Azko Nobel has 7% to 12% free fatty acids with 81% to 86% actives (INCI sodium cocoyl isethionate). 

It seems that some people have the idea that having stearic acid in our SCI isn't a good thing. Like everything in life, it depends upon the application (chocolate good in my mouth, not so good in my purse on a hot summer day). In my personal experience - and I recognize that the plural of anecdote isn't data - SCI with stearic acid in the INCI name doesn't agree with my oily hair when I put it into shampoo bars or liquid shampoo, but it's absolutely wonderful in body washes, facial cleansers, and other applications because it adds that wonderful creamy lather and lots of thickening to the product. So if you were to ask me if I thought SCI with stearic acid was a bad thing, I'd say no! It's great! But it doesn't work well for me in a shampoo for very oily hair.

In the interest of complete disclosure, I am writing this post because I received a phone call from Angie at the Herbarie. She has been asked the question about the SCI with stearic acid a number of times and was worried that I was saying that SCI with stearic was bad and wanted me to clarify this on the blog. SCI with stearic acid is not a bad thing. It's a very creamy feeling product with emolliency that will help thicken your products if you're making liquid surfactant mixes. And yes, all forms of SCI will have free fatty acids in them and the amounts differ depending on the manufacturer and the addition of extra stearic acid. Please stop asking her about her SCI! 

I hope I've clarified this!


Mychelle said...

I'm the proverbial straw that broke the SCI camels back. Sorry! I asked Angie about the differences in the SCI on the market and the stearic content of her flake, as I was get conflicting info on whether or not her SCI contained stearic, if it all contained stearic, etc. I really love the SCI I get from the Herbarie - I was just curious. =) Thank you so much for this post Susan, it is exactly the information I was looking for!

Crystal said...

How much stearic acid would you add to the granules from Aquarius-Aroma? I like the SCI from The Herbarie but I bought the granules from Aquarius-Aroma because it was cheaper but my formula is way too different with the granules.
I can't find the MSDS sheet for the SCI from The Herbarie.

Angie said...

Dear Susan and Blogger Friends, especially Mychelle :-)

I'm afraid Susan's recent post is still a bit misleading. Please let me try to clarify one more time.

First of all, we/I welcome questions about SCI or any of our products!! Please do not stop asking! My concern is about providing accurate information, not about people asking questions. Our best email address for questions is: ProductAssistance@theherbarie.com. Or you can call us at 803-364-9979.

Secondly, I will share my actual post to Susan which I hope will outline the difference in ALL the SCI products. If for any reason, this post doesn't clarify, then PLEASE do ask me for more information. If there is one thing I abhor, it's misinformation!

Thirdly, I'd like to let folks know that MSDS (Material Safety Data Sheets) are meant to provide safety information and are required by OSHA and therefore can be provided with first purchase of any product upon request. However, while the MSDS may contain some information about chemical composition, more than likely it will not. The best question is to ask your suppliers about specifications or typical analysis for the product you are interested in learning more about.

So here's the scoop and PLEASE do let me know if you have other questions.

Hi Susan,
I just left a voice mail message for you as a follow up to our discussion around SCI surfactants. I spoke directly with BASF R&D this morning and he confirmed that all SCI products (BASF, Clariant, etc) are basically manufactured the same way. The primary differences will be activity level and physical form. As you can see from the attached specification sheets, both Jordapon CI Prill and Jordapon CI Powder contain "free fatty acid" and the fatty acid profile is not specified. The same is true for the Clariant Hostapon products as I mentioned previously.

Clariant manufacturers Hostapon SCI 65, Hostapon SCI 78, Hostapon SCI 85 - all in different physical forms. Each of these will contain varying levels of free unreacted fatty acids (unspecified).

All SCI is derived from coconut oil and is considered biodegradable.

However, there is one BASF product that does contain stearic acid specifically. Jordapon CI 65% Flake is a specific blend of SCI and stearic acid and is different from all other SCI products. I believe this is where you might have gotten confused. Jordapon CI 65% Flake is specifically recommended for syndet bars, combo bars, facial cleansers, etc. So this one is different from all the others. It would be great if you could share this information on your blog to help clarify misunderstandings.

So, to sum everything up, all SCI products are manufactured the same way with varying activity levels. The only product that stands out a bit differently is Jordapon CI 65% Flake which does contain stearic acid. This product would perform differently and have a different feel due to the additional stearic acid.

I have also attached a file for Solubilizing SCI and hope you will find it helpful. Please feel free to share this email and any of the information on your blog.

I can see that you work very hard to provide accurate info for your blog friends and are doing a good job :-) If you have any questions about products that I am familiar with I will be more than happy to answer your questions.

Best Regards and have a nice day!

***********************************Angie Turner
The Herbarie at Stoney Hill Farm, Inc.
phone: 803-364-9979
fax: 803-364-9974
Visit our blog: http://theherbarie.blogspot.com/

Susan Barclay-Nichols said...

I'm not sure where my post differs from what you've written and where you feel I've been misleading. After a few e-mails and a lengthy conversation with you, I'm still not clear where our arguments diverge. To sum up my argument - SCI contains free fatty acids, and some companies add stearic acid to their SCI. I think your argument is that SCI contains free fatty acids, some companies add stearic acid to their SCI, and the SCI carried by the Herbarie doesn't contain stearic acid.

I know you take issue with my observations that SCI containing stearic acid isn't great for oily hair - you have argued there is no difference in SCI with stearic acid or without (or if there were, that the difference is so minute, no one would notice) and that my observations don't constitute scientific proof - but you haven't put that into this comment, so I'm still unclear why you would call me misleading (which is a very strong word to use, in my humble opinion).

Which SCI do you carry? Could you add a link to the data sheet in this thread? There's quite obviously interest in the surfactant products you carry.

There are many companies that manufacture SCI and there are two different manufacturing methods (click here and scroll to page 4 for more information, although the esterification route is apparently the more popular), and there are differences between the activity level and amount of free fatty acids, as well as the possibility that stearic acid has been added. For example...
Jordapon CI prill - less than 6% free fatty acid
Tauranot I-78 flakes: 10 to 12% free fatty acid, 80 to 82% active
Geropon (Rhodia) - less than 10% coconut acid, less than 25% stearic acid
Elfan (Azko Nobel) - 7 to 12% free fatty acid, 81% to 86% active

You mention a few others in your post. I'm not really sure where I'm "confused" about anything. I have stated that some SCI has stearic acid added to it and some doesn't. You've confirmed that some SCI has stearic acid and some doesn't. Again, not really clear where I'm confused or misleading people. Can you please clarify? (Please don't include your company name, address, website etc. as this could constitute advertising or imply that I am endorsing your company in some way.)

Angie said...

Dear Susan and Blog Folks,

Okie dokie, I'll keep it short and sweet :-) Here you go:

1) There are only two SCI flaked or powdered products currently being manufactured and sold that contain added stearic acid. One product is manufactured by BASF with the tradename of Jordapon CI 65% Flake. The product INCI name is Sodium Cocoyl Isethionate (and) Stearic Acid. The other product is manufactured by Clariant and the product tradename is Hostapon SCI-65C. The INCI name is Sodium Cocoyl Isethionate (and) Stearic Acid.

2) No other SCI products contain added stearic acid. But by nature of the manufacturing process all contain unreacted free fatty acids of unspecified composition. All of these products will have the INCI name of Sodium Cocoyl Isethionate.

3) BASF manufactures Jordapon Prill and Powder, both of which are minimum 84% activity - the remaining portion unspecified free fatty acids.

4) Clariant manufactures:
-(a)Hostapon SCI 85 C, G, P.
-(b)Hostapon SCI 78 C,P.
The numbers refer to activity level (85% or 78%)and the C, G, or P refers to the physical form (powder, granular, etc). Again, the activity level is the important factor and the remaining portion is always unspecified unreacted fatty acid.
-(c)Hostapon SCI 40L which is a dispersion and not a consideration in this discussion.

5) The Herbarie is currently selling Hostapon SCI 85G. If anyone has any questions about our SCI Flake or any of our other products, please do not hesitate to call or email us!!

6) Customer preference will determine which SCI product is most desirable for a particular formulation.

I hope this helps!

Best Regards,


Susan Barclay-Nichols said...

Hi Mychelle! We learn by asking questions! A curious mind is a wonderful mind and one that is open to learning (which I strive for every day!). Angie has said she's happy to answer them, so your apology is unwarranted! Take it back!

Hi Crystal! Jordapon prilled has less than 6% free fatty acid content and I can't find out how much Hostapon 85-G contains at the moment (I'll add it when I find it!) I tend to add 3% to the Jordapon prilled shampoo bars, and this gives it a nice creaminess. It's just a suggestion, but you might want to try that (or you could use acetyl alcohol or cetearyl alcohol for a nice feeling bar as well!) You'll have to do some experimenting to find what you like best!

Susan Barclay-Nichols said...

Hi Angie. I think there is the assumption that I have done one of two things - I have said that your SCI contains extra stearic acid and that SCI with extra stearic acid is a bad thing. It isn't a bad thing - it offers extra emollience to a product (which might not be desirable for those of us with oily hair). I have done much searching and I cannot find any reference to your SCI containing extra stearic acid (I know you haven't done a search, but I definitely encourage it because I can't find anything but would be happy to alter it if you did!) When I refer to SCI on the blog without specifying the supplier, I am referring to the Jordapon prills I buy from Aquarius. I have your flakes, but I don't use them as often as I do the prills (customer preference and all that). I have also purchased SCI from other suppliers so I could test out versions with extra stearic acid with those that don't contain it. So when I refer to SCI, I am not referring specifically to any products from your shop.

I did say that some flakes may contain extra stearic acid, which you say in your comment. I did not say your flakes contain stearic acid.

From what I can tell, this isn't about your company. This is about people who are really interested in what they are buying and feel comfortable asking questions of their suppliers. It wouldn't surprise me to learn that Aquarius and other suppliers offering SCI were getting similar questions!

As a second note, there are other companies that make SCI with added stearic acid, such as the Geropon (SCI by Rhodia), which contains 60% actives, less than 10% coconut acid, and more than 25% stearic acid and has an INCI of sodium cocoyl isethionate (and) stearic acid. And I'm sure there are others around the world (greetings to my international audience! I'm always thinking about products you might like to buy!)

There is one place where we differ: When we spoke on the phone, you said I was misleading my readers by stating that people with oily hair should probably avoid SCI with additional stearic acid in shampoo bars because there was no difference between SCI with extra stearic acid and SCI without extra stearic acid. I told you I disagreed with you - I have seen differences in those products, and as someone as oily hair, I was sharing my experiences with my readers. You said I was wrong, that you don't see a difference.

So here's my point - I find there is a difference between using different SCI products from different companies, between the prills, flakes, and noodles, and between that with added stearic acid and that without. Crystal notes in the comment above that she sees a textural difference between the two versions she owns, and I'm sure other readers of my blog have noticed differences. We aren't all wrong about having noticed differences.

If this is the only disagreement, then I think it brings the matter to a close.

Darlene Sandau said...

I have been using jordapon prilled which I can no longer find to make ny shampoo bars. Can I just use sci instead. Would it feel the same. Thanks in advance

Susan Barclay-Nichols said...

Hi Darlene. It depends on the make-up of the SCI you're using. Prills have a very specific feel and don't have the extra stearic acid that others might. It depends upon using the noodles or the flakes and so on. You'll have to experiment to see what you like best.

karalee said...

I just made a recipe microdermabrasion recipe with ecomulse, cetyl alcohol, stearic acid, btms25, aluminum oxide, some oils and aloe and the second I added SCI (powder) the cream turned to liquid. Is that normal?

Susan Barclay-Nichols said...

Hi Karalee! It sounds like your emulsion broke. You can't mix Ritamulse and BTMS as they are opposite charges.

Faith Frankenfield said...

Hi Susan- I purchased SCI from Ingredients To Die For. Before this I had been using a powder form- this comes in small noodle form. Its smaller than the current noodle. I always add Stearic Acid to my formula at about .5%. This time the shower gel turned out so thick!!!! Ingredients to Die For lists their INCI as Sodium Cocoyl Isethionate. Do you know whether theirs has Stearic Acid already and just doesn't list it on the INCI? Its the only reason I can think of why the end product turned out to be so thick.

Susan Barclay-Nichols said...

Hi Faith. I have found that the prills or small noodles are less thickening than the larger noodles or pellets. When I have looked at the data bulletins for these different ones, there is a difference in various free fatty acids - including stearic acid - which will thicken your product, something that is not noted in the very simple INCI. I would ask your supplier for more information or ask for their data bulletin.

My guess is that this is the difference with the two ingredients for you!

I am always apprehensive about this topic as I have been raked over the coals about this before, and I do not need more drama in my life. Strange that a discussion about surfactants could be so emotionally charged, eh?

griffin oomen white said...

Hi Susan!
I'm trying to formulate an anhydrous oil cleanser using decyl glusoside and sodium cocoyl isethionate as surfactants. Since the decyl glucoside is oil soluble and the sci is surfactant soluble so I melted them together and I figured I could just add the oils to those two but it separates into lumps and wont melt together. Do you have any solutions for incorporating the oils and surfactants?

Susan Barclay-Nichols said...

Griffin, a few thoughts...
1. Decyl glucoside isn’t oil soluble.
2. Decyl glucoside doesn’t dissolve SCI properly. I don’t know what surfactant soluble means as I’ve never heard that phrase before, but SCI is water soluble--ish. Do you mean that SCI dissolves better in surfactants? This is true, but only certain ones. The lumps are the SCI not dissolving.
3. If you have decyl glucoside in a formula, it isn’t anhydrous as that word means “without water” and decyl glucoside contains water.
4. This surfactant mix has a very high pH, so you’d need to alter it pretty dramatically.

I’m not sure where you found that information or formula, but I’d offer feedback to the writer that there is so much wrong here. This formula could never work as you’d need an emulsifier, and both that and the oils would suppress foam to the point of being negligible. The pH would be quite high and you’d need a preservative.

Hope this helps...