Ingredient review
Trideceth-9 PG-Amodimethicone
INCI: Trideceth-9 PG-Amodimethicone
A gentle, modified silicone that smooths hair and skin without heavy buildup, but may not suit those avoiding all silicones.
In plain English
This is a special type of silicone that has been chemically tweaked to be more water-friendly and less likely to build up on your hair or skin. Unlike older, heavy silicones, it can be washed out more easily with regular shampoo. It works by forming a very thin, flexible film that smooths the outer layer of your hair or skin, reducing friction and making things feel silky and soft.
Review score
Safety, usefulness, and evidence
Potentially useful with some tradeoffs
The evidence base is useful, but some claims depend heavily on the formula.
Risk flags are low for most users, though the finished product can still irritate.
- Source
- synthetic
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Useful, but context matters
Trideceth-9 PG-Amodimethicone is generally a lower-concern ingredient when the full formula suits your skin.
Plain-English read
Treat this as a practical screening step before you compare products that contain this ingredient.
- Step 1Start with the score, then check the irritation and clogging risk before judging Trideceth-9 PG-Amodimethicone.
- Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
- Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.
Score terms in plain English
Irritation risk
lowLess likely to sting, burn, or bother most users, though sensitive skin can still react.
Clogging risk
lowLess likely to feel heavy or contribute to clogged pores for most skin types.
Evidence level
moderateThere is useful support, but formula details and claim strength still matter.
What it is
A synthetic silicone polymer modified with propylene glycol (PG) and a trideceth-9 chain, making it more water-dispersible and less prone to buildup than traditional amodimethicone.
How it works
It deposits a thin, positively charged film onto negatively charged hair or skin surfaces. This film smooths the cuticle, reduces static, and adds shine without a heavy or greasy feel. The PG modification helps it rinse out more easily.
Pros
Lightweight conditioning
Provides noticeable smoothness and shine without the heavy, greasy feel of some older silicones.
Easier removal
The PG modification makes it more water-dispersible, so it rinses out more easily with standard sulfate-free shampoos.
Cons and cautions
Still a silicone
If you are avoiding all silicones for environmental or personal reasons, this is still a synthetic silicone polymer.
Potential buildup over time
Though improved, repeated use without occasional clarifying can still lead to some accumulation on very fine or low-porosity hair.
Best for
- People with frizzy or dry hair wanting smoothness
- Those who like silicone benefits but worry about buildup
Use caution if
- Strict 'no-silicone' or 'no-synthetics' routines
- Very fine, low-porosity hair that easily gets weighed down
Usage tips
Safety summary
Considered safe for topical use in cosmetics at typical concentrations. Low irritation and comedogenic potential. No significant safety concerns reported in regulatory reviews.
Research notes
Limited independent peer-reviewed studies on this specific molecule, but it is a well-established variant of amodimethicone. Safety is supported by industry data and regulatory acceptance.
Common label clues
- Typical concentration
- 0.5% to 5%
- Regulatory status
- Approved for cosmetic use in the EU, US, and most major markets. No known restrictions at typical use levels.
- Common uses
- Conditioners, Hair masks, Leave-in treatments, Shampoos, Styling products, Body washes
- Environmental note
- Silicones in general are not readily biodegradable, but this modified version is designed to be more easily removed in wastewater treatment than older silicones.
Good to know
- Often listed near the end of ingredient lists because it is used at low concentrations.
- Commonly found in 'silicone-free' marketed products that actually contain modified silicones.
Common questions
What is Trideceth-9 PG-Amodimethicone in beauty products?
This is a special type of silicone that has been chemically tweaked to be more water-friendly and less likely to build up on your hair or skin. Unlike older, heavy silicones, it can be washed out more easily with regular shampoo. It works by forming a very thin, flexible film that smooths the outer layer of your hair or skin, reducing friction and making things feel silky and soft.
What does Trideceth-9 PG-Amodimethicone do in a beauty product?
It deposits a thin, positively charged film onto negatively charged hair or skin surfaces. This film smooths the cuticle, reduces static, and adds shine without a heavy or greasy feel. The PG modification helps it rinse out more easily.
Is Trideceth-9 PG-Amodimethicone safe for most people?
Considered safe for topical use in cosmetics at typical concentrations. Low irritation and comedogenic potential. No significant safety concerns reported in regulatory reviews.
Who should be careful with Trideceth-9 PG-Amodimethicone?
Strict 'no-silicone' or 'no-synthetics' routines Very fine, low-porosity hair that easily gets weighed down
Research sources
Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.