Sunday, May 10, 2009

Better crafting through chemistry: Dimethicone

I mentioned silicones in the post on occlusives and if you've read any of my hair care posts, I consider dimethicone to be a major part of my anti-frizz routine, but dimethicone is great for body care products as well.

What is dimethicone? Dimethicone is a non-volatile oil soluble silicone you can add to your hair and body care ingredients.

In body care products, it works as a barrier ingredient, emollient, lubricant, carrier/diluent detackifier, and and skin protectant (one of three approved by the FDA). You can use it in products as diverse as body lotion and lip balm to offer shine, glide, and protection from the elements.

In hair care, it improves wet and dry combing, helps with shine, improves hair feel (softness), reduces static charge, and works as a humidity resistor. And in colour cosmetics, like foundations, it is a lubricant, spreading agent, emollient, and diluent/carrier ingredient.

Is there anything dimethicone can't do?

Yep, it can't create world peace. Although if everyone had shiny, soft, manageable hair, perhaps the world would be a nicer place and people might get along better...but I digress.

How does it perform such miracles?

Dimethicone tends to migrate to the surface of your hair or skin, forming a nice film that not only protects your skin, but keeps all the good stuff you've put into your lotion or conditioner to your skin or hair.

Dimethicone is rated by c.s. or centistrokes. The higher the c.s., the thicker you'll find your dimethicone. 350 c.s. is considered as thick as mineral oil (so thicker than shampoo, but not as thick as ketchup), whereas dimethicone 1000 c.s. is going to be as thick as motor oil (so thicker than ketchup, but not as thick as molasses). So why should you care about the centistrokes? The lower the centistrokes, the quicker surface if you have the 350 c.s., it is going to spread quicker than the 1000 c.s.

As an aside, these descriptions of viscosity are given by the manufacturers of dimethicone, and I think they're not great. Really, do I want to use the words "motor oil" when I'm trying to tell you about this wonderful product that will bring shine and manageability to your hair? I know I'm picturing my hair dripping with grease...not a nice image.

So why use the 1000 c.s. (like I do in my hair care products)? Because it will form a nicer, more long lasting barrier for hair in humidity, for instance. I like to use the 350 c.s. in body care products; 1000 c.s. in hair care products.

It is non-volatile over 5 c.s., meaning it won't evaporate from your skin or hair like cyclomethicone will.

Given this giant list of things dimethicone can do...well, I think we're going to need a little more than one post to discuss the awesome power of this silicone...

The quick summary - dimethicone is not suitable for water only products, like toners, but works well in lotions, surfactant systems, conditioners, and other surfactant or emulsified products. Use at up to 5% - although I like 2 to 3% - in these systems.


Anonymous said...

Can solid shampoo be made without the dimethicone ?

FMN said...

Can a good solid shampoo bars be made without the dimethicone ?

Susan Barclay-Nichols said...

Yes. Dimethicone is in the shampoo to help with frizzing and conditioning. You can choose to leave it and other silicones out, if you you want.

I did do a post onsilicone alternatives, if you are interested.

pearlyn said...

hi babe.

i noticed dimethicone is always added in the cool down phase. what will happen if i add it in the heated phase?

is an emulsifier needed when there's silicone in the formula?
assuming there's 1% of dimethicone, is 0.25% emulsifier required?

Susan Barclay-Nichols said...

Dimethicone should be added to the cool down phase. (I've never used it in the heated phase, so I can't tell you what will happen.) If you are using dimethicone, you need an emulsifier or it will separate. There are water soluble dimethicones you can use in a product - I think the Herbarie might carry it - and you don't need an emulsifier for that one.

It depends on the emulsifier - you can't emulsify it with polysorbate 20 or 80, it has to be a proper oil in water emulsifier, like Polawax or BTMS. BTMS is a better emulsifier of large amounts of silicone, but 1% isn't considered a large amount. There are some emulsifiers for silicones - the Herbarie and Lotioncrafter carry these - if you want to make something like a serum.

Tanna said...

If you add dimethicone to a hot product it will go jelly like and will not incorperate into the product smoothly.

Natalia said...

Hi Susan! I used dimethicone 1000cs for my lotion. I feel that the lotion is a bit sticky after my hands dry up. Could that be the cause? I also applied it in the heating stage but the product seemed like it mixed well. do you think using 350 instead will solve my problem? Thanks!

Natalia said...

i just tried 350 cs but stick a bit sticky. can ceteareth 20 be the cause?

Natalia said...

does glycerin cause stickiness? can i take it out if it does?

Susan Barclay-Nichols said...

Hi Natalia. I'm afraid I can't comment much without your recipe. 1000 cs will stay around longer than 350 cs dimethicone, which is the the point of using the higher cs. Please don't use it in the heated phase - it can ruin your emulsion and feel quite unpleasant.

Glycerin can cause stickiness - you can substitute another humectant like sodium lactate or sodium PCA or it. Ceteareth-20 shouldn't cause stickiness - I've always found it to be quite creamy and nice on my skin.

If you can send me your recipe, perhaps we can find the culprit!

Natalia said...

Hi Susan! I used EDTA and glycerin, Cetyl, Stearyl, Ceteareth 20, Olive Oil, Grapeseed oil, dimethicone, titanium dioxide, fragrance, preservatives and citric acid. I actually put the dimethicone when the products goes down to about 60C. is that ok or should i put it when its below 45C? Also any big advantage if i use dimethicone 350 instead of 1000 or is 1000 fine? i'm also thinking of adding triglyceride to make the product feel creamier. Thanks!

Susan Barclay-Nichols said...

Hi Natalia. Looking at your recipe, it could be one of many things. You have quite a lot of fatty alcohols in there, some of which can feel quite occlusive and grippy in a lotion. The glycerin will contribute to stickiness - I'm not sure how much you're using, but I find anything over 3% to be sticky feeling - as will the 1000 cs dimethicone as it will form a more occlusive layer for longer than the 350 cs. You might want to consider using greasier oils - grapeseed can feel quite dry on our skin - or lighter oils. I'm sorry if I sound like I'm fishing around for ideas, but I can't see one specific culprit that could be making the lotion feel sticky, except for the glycerin. I'd take that out and try using something like sodium lactate as your humectant and see if you get the same effect.

What are you using for your emulsifier? I see high HLB emulsifiers, but not low HLB ones?

Natalia said...

Hi Susan! Thanks for your inputs. I used Glycerol Distearate as my low HLB. Have a great weekend!

Anonymous said...


I'm looking for ingredients that add shine to hair but no silicones. If anyone knows of any oils that can help add shine, by even a little, bit please share the information. Thanks everyone.

Susan Barclay-Nichols said...

Here's a post on the topic of silicone replacements and here are the emollient posts, where you'll find all the information on oils, esters, and butters. Hope this helps.

Sara said...

Hi Susan!
Can dimethicone cause acne? Some websites say that oil-soluble dimethicones can cause acne because they also trap oils, bacteria, etc. to your skin. The only positive thing I could find is that water-soluble dimethicone doesn't cause acne because it allows your skin to breath. Is this true? I want to use a dimethicone in my face lotions, but have major issues with acne. So I was thinking about finding a water-soluble one instead. I would appreciate any advice! Thank you! :)

Debbie said...

Hi there! I was wondering if it is possible to form a gel with dimethicone. If so, what would I use? Would I use a gelifier that I would use with, say, olive oil?

Bhavana Doshi said...

Hi Susan,

Ur info is amazing on these ingredients. I'm from India and after contacting many suppliers I find that BTMS-50 is unavailable. I can however find e-wax available which i use in my lotions. My question to u is it okay to use E-wax NF if i want to add dimethicone in lotions and hair conditioners?

Bhavana Doshi

S Hoban said...

I have an UNUSUAL question :) I'm trying to duplicate a kinetic play sand that my sister purchased at a local fair. It's wonderful stuff, pliable and mold-able but doesn't stick to any thing but itself! Super clean. After a bit of research I found the manufacturer's medical sheet lists 99% sand and dimethicone (it doesn't give the amount of dimethicone but one assumes it would be 1%). So, I bought some dimethicone 500 cps and crafting sand to try it out. I started with one cup of sand and worked up to around 3.5 oz dimethicone. It has the right "look" and is mold-able but my sand sticks to my fingers. Very messy. Any ideas?

Anonymous said...

To s Hoban.....

I have been wanting to replicate it as well. I read the sand needed to be heated in the oven at 250 for several hours to ensure there was no moisture. I wonder if any moisture that was in the sand is causing sand to stick? Maybe the cps needs to be higher? Email Me if you can and let me know how it turns out. 15 bucks a package is too much for play would be great to make it at home.

Comfyjunojeans@ gmail.

Brittany Allen

Grammy T. said...

I' d like to know how much dimethicone to add to a recipe with that would make about a cup and 1/2 of lotion.

Susan Barclay-Nichols said...

Hi Grammy T. I'm sorry but I don't know how much you would need for a volume measurement. I would generally add up to 5% in the cool down phase of a product, but that is 5% by weight.

Aesthete said...
This comment has been removed by the author.
Aesthete said...

Hi Susan,

I love using dimethicone in my products but I recently came across an article on Personal Care Truth that stated Dimethicone blocks the skin's ability to naturally perform the functions of excretion, absorption, respiration and regulation. There were no links to studies and I couldn't find anything on the web. I was wondering if maybe you had come across any information relating to it or offer some insight as to why that would be stated.

Tammy said...

Hi Susan,

I made a very thick cream for a friend whose daughter has severely dry, chapped skin on the backs of her hands and her knuckles. It turned out really well, but I wanted to try a version with dimethicone as well. I replaced 2% of the oil with 2% dimethicone and the emulsion failed when I added the cool-down phase. I had used e-wax in the first try and so I retried it with BTMS-50 but I had the same problem -- a beautiful lotion until cool-down. I use Optiphen Plus as my preservative and I know some people have trouble with it but I've only ever had one lotion failure in the past two years and that was due to green tea extract. I'm wondering if you can help me out. Is there more I should know about dimethicone? I tried to read all of your posts on the subject but I'm still not sure where I've gone wrong. Here is the recipe:

Water Phase
Water, Distilled 51.2
Oat Protein, Hydrolyzed (Cromoist) 2.0
Glycerin 2.0
Sodium Lactate 2.0
Powder, Allantoin 0.5
Powder, Aloe Vera 200X 0.3

Oil Phase

Butter, Cocoa – Natural 10.0
Oil, Rice Bran 8.0
BTMS-50 7.0
Oil, Soy Bean - Non GMO 6.0
Lecithin, Liquid 2.0
Stearic Acid 2.0
Cetyl Alcohol 1.0

Cool down

Powder, Panthenol B5 2.0
Dimethicone 350 2.0
Vitamin E 1.0
Optiphen Plus 1.0

Thanks :)

Susan Barclay-Nichols said...

Hi Aesthete. I'm shocked that such a fear mongering, non-evidence based opinion piece ended up on Personal Care Truth! That is a ridiculous piece of writing! I wouldn't take anything in that post as being truthful. Honestly, I'm so shocked to find that on such a reputable site!

Hi Tammy. I have no idea why the recipe isn't working. There isn't anything obvious there. You have a 35% oil phase, which is high but not the highest I've seen. Maybe 7% BTMS-50 isn't enough? Sorry, I simply don't know...

sfs said...

Tammy, ditch the Optiphen! I had the same trouble with my lotions breaking during cool down when I used Optiphen as my preservative. It was very difficult for me to figure this out because the lotion failure was inconsistent. Sometimes it would break and sometimes it wouldn't. My procedure and ingredients would be the same but the outcome seemed random. I have never had a failure with my reliable lotion formulae since changing my preservative. My experimental formulae are a whole different story, however! ;)

Rocio GarcĂ­a said...

Hi dear Susan:

I have a question: What is Acive % for Demethicone 350cs?

I really appreciate your help.

My best regard.

Susan Barclay-Nichols said...

I think you need to ask your supplier. But as far as I know it is 100% dimethicone.

Gia Volpe said...


I've been eyeing the products from Paula's Choice and love that I can look at the ingredients now and figure out how to make it myself, even better. I generally don't buy her products based on a lot of the biased information she posts.

But this has me stumped!

The ingredients to this antiredness lotion have dimethicone listed twice. Is there a reason for this?

Susan Barclay-Nichols said...

Hi Gia! There's supposed to be no comma between Triethoxysilylethyl Polydimethylsiloxyethyl Hexyl dimethicone in the ingredient list. There are many types of dimethicone, and obviously she uses two different ones in this product!

Christine said...

A search for the info in that Personal Care Truth article brought me to this post on your always wonderful blog. I'm glad to see it confirmed that the article was as bad as I thought. I'm surprised it's on an otherwise excellent site, and that none of the commenters call out the claims made.

Anonymous said...

Hey Susan,

I am trying to create a mixture to moisturize and protect my antique leather couch at home from drying out or cracking and to also preserve its beautiful brown color. I heard pure silicon oil 350 (not emulsion) would be great, but I was wondering if I should mix it with another kind of oil to give maximum moisture to my leather?

HG moisturizer said...

Hi Susan!

May I ask where you get your 1000 cst dimethicone from? I can't seem to find any suppliers in the US for it.

Thank you for sharing your knowledge with us!


Susan Barclay-Nichols said...

Hi Ghalia. I'm sorry I missed your comment! I'm afraid I know nothing about leather and can't really help out with leather.

Hi HG moisturizer! I can't find it anywhere any more. I'm sorry I couldn't be of more help.

Tammy said...

Hi Susan,

I read your recent post about comments and I realized that I am one of the guilty ones -- not getting back to the discussion to provide feedback!! Sorry :(

I posted a question about lotion failure with Dimethicone 350. I abandoned the quest for a while and then revisited it a few months ago. Since I really like Optiphen Plus, not least for preserving the headspace in bottles, and I've never had a lotion failure with it besides this cream, I decided to revamp the emulsifier. I lowered the BTMS 50 to 6% and added 4% E-Wax NF and the cream turned out incredibly well. I was very happy and so was the friend I was making it for.

Thanks again for all the work you do.....there is no one out there like you :)

Susan Barclay-Nichols said...

Hi Tammy! Thank you so much for sharing your experiences! And your kind words! I'm blushing!

Gerardina Giorgio Boisvert said...

DIMETHICONE is a CARCINOGEN. Are you aware of this and so are many other ingredients which you use in your creams.

Susan Barclay-Nichols said...

I don't think this is the blog for you.

Manaza Mitha said...

Hello there,

Thank you very much for this blog.

I used both dimethcone and isododecane in my lipstick formula. Since it was more a melted lipstick formula does not require heat.
The dimethcone and isododecane were added to a variety of carrier oils such as fractionated coconut oil, castor oil, jojoba oil; as both silicones are mixable with an anhydrous formula.

after I mixed the above I added some vitamin E (tocopherol) and peppermint essential oil.

As for the filler, this was comprised of diverse powered mineral fillers, including kaolin, Magnesium stearate, zinc oxides, mica and carmine

I then mixed the oils with the filler.

What I observed was that there was a layer of floater oil and a white cast lingering around in my beaker. Now my question to you is why do you think that the oils didn't mix? and the white cast, I have no idea why that is lingering around. Was it due to the dimethacone and isododecane not mixing well with one of the oils that i used? and for the white cast, was it because the pigments were not dispersed?

Any advice would be MUCH appreciated.


Camirra Williamson said...

Hey! I have an ingredient that I think you should try if you can get your hands on it. Its not been talked about too much on the blog, though referenced to. I REALLY like amodimethicone in my leave in spray and deep conditioner. plus it only takes a little to get the effect, like .5-1% in my experience. a real step up from dimethicone, which I also love. my hair is super shiney and soft after using s leave in spray with it. and I have african hair which is usally dry, so you know it works lol. basically your same leave in recipe except I left out the cyclometicone and subed 1% amodimethicone. try it if you can!