Encyclopedia · silicone
Bis-aminopropyl dimethicone
An amino-terminated silicone related to amodimethicone, used in conditioners and colour-care products to stick to damaged hair.
What it is
Listed in the Cosmetic Ingredient Review report as "amino bispropyl dimethicone" alongside dimethicone and amodimethicone. The panel concluded these are safe as used in cosmetics, at up to about 15%. Nair 2003
Do not confuse it with bis-aminopropyl diglycol dimaleate, the Olaplex active, which is a different molecule.
How it works
Terminal amine groups give it a positive charge, which favours attachment to negatively charged damaged hair. The general rationale is supported by Labarre 2023 but was not tested on this ingredient.
What the studies show
- We found no hair-specific efficacy data.
Side effects and safety
Judged safe as used. Nair 2003
Bottom line
It behaves like amodimethicone. It is fine for damaged hair, but no unique benefit is proven, so we are not very sure it does more. See silicones.
Studies 2
Nair B, Cosmetic Ingredient Review Expert Panel. Final report on the safety assessment of stearoxy dimethicone, dimethicone, methicone, amino bispropyl dimethicone, aminopropyl dimethicone, amodimethicone, and related silicones. Int J Toxicol. 2003
Result: The panel judged dimethicone and the amino-silicones safe as used in cosmetics, with minimal absorption.
Read the study ↗Labarre L et al. Hair surface interactions against different chemical functional groups as a function of environment and hair condition. Int J Cosmet Sci. 2023
Result: Hydrophobic interaction drove deposition on virgin hair and electrostatic interaction on bleached hair.
Read the study ↗Related
- AmodimethiconeA dimethicone with positively charged amine groups, so it clings to damaged hair and resists rinsing better than plain dimethicone.
- DimethiconeThe standard hair silicone, a water-insoluble oil that coats the fibre for slip, shine and friction control without repairing anything.
- Bis-aminopropyl diglycol dimaleateThe active in Olaplex; it strengthens bleached hair in the lab, but the claim that it re-links broken disulfide bonds has never been independently confirmed.
- Silicones in hair careSilicones coat hair to cut friction and add shine without repairing it; buildup is real but manageable, and the scare claims are unsupported.