Ingredients Dictionary: Stearamidopropyl Dimethylamine

Today's ingredient is quite a mouthful! Therefore, I placed a nice picture of my obscene collection of  Herbal Essences conditioners in which you can find this ingredient!.



Stearamidopropyl dimethylamine is one of the leading 'replacements' for silicones in conditioners (For Tresemme Naturals fans - this is the lead surfactant in your conditioner). I placed the word replacements in quotes because it is not always strictly a replacement, sometimes it is added in conjuction with a silicone as happens with Herbal Essences (so in short, do not think that seeing it on the ingredient list means that the conditioner is silicone free).



Anyway, here are its properties!

STEARAMIDOPROPYL DIMETHYLAMINE
Property	Notes
What is it?	A cationic surfactant (a positively charged surfactant)
Where is it derived from?	Vegetable oil (rapeseed)
Is it water soluble?	Yes
ACTION IN HAIR CONDITIONER
What does stearamidopropyl dimethylamine do in shampoo and conditioner?	As it is a surfactant it can to some extent help blend the oil and water components of conditioner.
How much  is added to conditioner?	Typically conditioner contains less than 5% stearamidopropyldimethylamine
Is it  a major component of hair conditioner?	It is usually within the top 5 ingredients if present in a conditioner
ACTION ON HAIR
Does stearamidopropyl dimethylamine do anything to hair itself	1. It binds (adsorbs) to the surface of  hair 2. Its positive charge helps correct the negative charge from shampooing. 3. It  gives slip to hair without causing excessive build up because it is water soluble unlike oils or silicone 4. It helps to smooth the cuticle and prevent static build up (flyaways!).
Does it penetrate hair?	It is not known to.
Is it better than silicone for detangling and slip?	Not necessarily. Some people may find a silicone free conditioner with stearamidopropyl dimethylamine good enough but others will not. It is up to the consumer (i.e you) to test it.

Sources
 

Cosmetics and Toiletries Manufacture Worldwide, 271–276, 2000.


International Journal of Cosmetic Science, 32, 246–257, 2010.