PEG/PPG-18/18 Dimethicone

What is PEG/PPG-18/18 Dimethicone?

PEG/PPG-18/18 Dimethicone is a synthetic copolymer derived from dimethicone, a silicone polymer, modified with polyethylene glycol (PEG-18) and polypropylene glycol (PPG-18) side chains. This hydrophilic modification enhances its water solubility compared to pure silicones. Primarily used in rinse-off and leave-on cosmetics like shampoos, conditioners, moisturizers, and sunscreens, it functions as a non-ionic surfactant and emulsifier. It lowers surface tension to stabilize water-in-silicone emulsions, preventing phase separation and enabling lightweight, spreadable formulas. The PEG/PPG chains allow even dispersion of ingredients, while the silicone backbone delivers a silky, non-greasy finish and improves product flow during application on skin or hair.

Comedogenic Rating 0/5 Low risk of clogging pores
EWG Safety Rating 3 View on EWG →

Roles in Formulation

This ingredient serves the following purposes in cosmetic formulations:

Surfactant
Lowers surface tension to enable cleansing, emulsifying, and foaming; central to shampoos, body washes, and many emulsions and micellar systems.
Emulsifying agent
Enables stable mixing of oil and water phases by forming an interfacial film, helping create lotions, creams, and cleansers with consistent texture.

Benefits

Stabilizes oil-water mixtures for consistent, long-lasting product textures.

Imparts a smooth, slippery feel that enhances application and spreadability.

Facilitates gentle cleansing in wash-off products without heavy residue.

Who It's For

A quick guide for who this ingredient may suit (and who should be cautious).

Who May Benefit Who Should Avoid
Users preferring lightweight, quick-absorbing emulsions in daily skincare.
People with known sensitivity to silicone polymers.
Individuals with normal or combination skin types seeking non-greasy hydration.
Those avoiding PEG-modified ingredients due to contamination concerns.
Hair care enthusiasts wanting improved detangling and manageability.
Consumers preferring all-natural, silicone-free formulations.

Safety Notes

  • EWG rates it as moderate hazard (score 3), mainly from potential impurities in PEG components.
  • Regulatory reviews affirm safety in cosmetics at typical use levels with low skin penetration.

Frequently Asked Questions about PEG/PPG-18/18 Dimethicone

Is PEG/PPG-18/18 Dimethicone pore-clogging?

It has a comedogenic rating of 0, indicating low risk of blocking pores.

What makes it different from plain dimethicone?

PEG and PPG chains add water-loving properties for better emulsifying in water-silicone blends.

Is it suitable for sensitive skin?

Generally low irritation, but those with silicone sensitivities should patch test.