It's up in articles, under Hair Care. I'll see what other articles I have saved and repost them for you all!
In Nightshade's quote, I find it strange that the cyclomethicone should be able to evaporate so quickly, whilst being a very large molecule. So I am not so sure about the truth of the rest they are telling..
It's up in articles, under Hair Care. I'll see what other articles I have saved and repost them for you all!
This might be more of an answer than you want... Dimethicone is a very large molecule, it's a polymer that can contain thousands to millions of repeat units. I've always theorized that it was a bit easier to wash off of the hair because of this, but due to it's size it won't really ever evaporate off the hair or skin.
Cyclomethicone on the other hand is a small cyclical loop of 5 repeat units, making it much more volatile (can evaporate off), and in my mind, much more likely to get stuck underneath a hair scale... perhaps making it more difficult to wash off.
Anyway, there's my chemical knowledge of silicones.
Ah... I know quite a bit about chemicals, but I didn't know the structures of the 'cones... so thanks for your explanation! If it is that small, it could actually evaporate, so I am sorry about what I've written above.
Cyclomethicone could stick better to the hair because it is smaller... and the keratin in the hair is not neutral, but charged, so large, unpolar molecules (silicones) could have more difficulties to stick to that polar environment than small molecules have...
Where did you find your information about silicone structures?
Henna, Herbal Coloring,Damaged Hair Articles
Thanks for all replies... but I am still in the static zone today.
Frannyg I didn't feel that happy about continuing using coconut oil (ears down) as it gave great shine - but made my hair crunchy (whether applied wet or dry). So I don't know...
Ooo - a scientific debate, but it is all beyond me! All I know is that the conditioner I'm looking at at the moment appears to have only one 'cone in the mix, and that is written as 'Dimethicone Propyl PG-Betaine' although the way it's printed, it could be that it ends with the 'PG-' bit! Sorry, I am no scientist...
I'm somewhat familiar with the structures from work (I work in a lab with a few chemists). Here's a couple of links to dimethicone (PDMS) and cyclomethicone structures though.
That link says that regarding water solubility - Dimethicone is INSOLUBLE. I thought it was water soluble! Help! It's the only one I have in the house (conditioner) and I'm not letting it near my hair if it 'aint water soluble...
ETA I found this site: www.gina.antczak.btinternet.co.uk/CU/ING.HTM. It describes my Dimethicone Propyl PG-Betaine (in conditioner) as a synthetic silicone polymer, with functions being those of Antistatic and Surfectant... Is this a goodish silicone or one of the worst types?
Sorry to keep asking questions!
Last edited by Celebrian; March 13th, 2008 at 01:24 PM.
My understanding is that unless it's stuck to something else (usually a PEG) silicones are rarely soluble in water. There are some chemicals that can be added that will make the silicones go into solutions, detergents being one of them. I'm not really sure what the PG-Betaine addition does. Maybe I'll go play on google a bit.
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