What Is Bis-(Methoxy Peg-11 Epoxidized Soyate) Peg-9?
Bis-(Methoxy PEG-11 Epoxidized Soyate) PEG-9 is a plant-based ingredient made from soybean oil. Chemists start with natural soy fatty acids, turn them into a more reactive form through a process called epoxidation, then attach small chains of polyethylene glycol (PEG). The last step links the material to PEG-9, giving it water-loving properties that help it mix evenly in cosmetic formulas.
The move toward gentle, plant-derived surfactants in the 1990s sparked interest in modified soy oils. Brands wanted alternatives to harsher cleansers like sulfates, so suppliers developed this PEG-soy blend. Today it is produced in large reactors where temperature and pH are carefully controlled to keep the fatty acids stable while the PEG units are added.
You will most often see Bis-(Methoxy PEG-11 Epoxidized Soyate) PEG-9 in liquid and cream formulas that need mild yet effective cleansing or emulsifying power. Typical products include facial cleansers, micellar waters, shampoos, body washes, makeup removers, sheet mask essences, lightweight moisturizers and even some baby care items where gentleness is key.
Bis-(Methoxy Peg-11 Epoxidized Soyate) Peg-9’s Cosmetic Benefits/Uses
This multitasking ingredient contributes several helpful actions in a single formula:
- Cleansing: Lifts away dirt, oil and makeup without stripping the skin or hair
- Dispersing: Keeps powders, color pigments or exfoliating beads evenly spread so they do not clump at the bottom of the bottle
- Emulsifying: Helps oil and water mix, allowing brands to create stable creams, lotions and milky cleansers
- Foam Boosting: Enhances the amount and stability of lather in washes and shampoos for a richer, more satisfying feel
- Solubilizing: Allows small amounts of fragrance oils or active ingredients to dissolve in water-based products, preventing separation or cloudiness
Who Can Use Bis-(Methoxy Peg-11 Epoxidized Soyate) Peg-9
Thanks to its mild, plant-based nature, this ingredient is generally well tolerated by most skin types including dry, oily, combination and sensitive skin. Those with a known soy or PEG allergy should avoid it since the molecule is sourced from soybean oil and contains polyethylene glycol chains.
Because it is derived entirely from plants and contains no animal by-products, Bis-(Methoxy PEG-11 Epoxidized Soyate) PEG-9 is suitable for vegetarians and vegans. The production process relies on soybeans and synthetic PEG units, not animal fats or proteins.
Current safety data shows no specific hazards for pregnant or breastfeeding women when the ingredient is used topically at the concentrations found in cosmetics. That said, this is not medical advice; anyone who is expecting or nursing should run any skincare product past a qualified health professional before adding it to a routine.
The ingredient does not make skin more sensitive to sunlight so it is considered non-photosensitizing. It also has a low likelihood of clogging pores, works well alongside most actives and is biodegradable, which appeals to eco-conscious users.
Potential Side Effects/Adverse Reactions
Reactions to topical Bis-(Methoxy PEG-11 Epoxidized Soyate) PEG-9 differ from person to person. The points below outline potential side effects, although they are unlikely for most users when the formula is made correctly.
- Mild stinging or redness, especially on very reactive skin
- Contact dermatitis in individuals sensitive to soy or PEGs
- Transient eye irritation if a cleanser or shampoo accidentally gets into the eyes
- Rare allergic rash accompanied by itching or swelling
If you notice any of these issues while using a product that contains this ingredient stop using it immediately and consult a healthcare professional.
Comedogenic Rating
Rating: 1/5 Bis-(Methoxy PEG-11 Epoxidized Soyate) PEG-9 is highly water soluble thanks to its PEG groups and it rinses off the skin without leaving a thick, occlusive film. The soy-derived fatty portion is chemically modified to be far less greasy than raw oils so the likelihood of it blocking pores is very low. Because of this, it is generally suitable for people who are prone to acne or breakouts.
Minor formulation factors such as heavy butters or silicones used alongside it can affect the overall comedogenicity of a finished product, but the ingredient itself poses minimal risk of pore clogging.
Summary
Bis-(Methoxy PEG-11 Epoxidized Soyate) PEG-9 acts as a gentle multitasker that cleanses, disperses, emulsifies, boosts foam and solubilizes small oily components. Its PEG chains attract water while the soy backbone grabs onto oil so it bridges the gap between the two phases and keeps formulas stable and effective.
The ingredient is not a household name yet it has a steady following among formulators looking for plant-based alternatives to harsher surfactants. You will mostly find it in mild facial cleansers, micellar waters and baby washes rather than in bold marketing campaigns.
Current data shows it is safe for topical use with a low rate of irritation or pore clogging. As with any new skincare product, give your skin a chance to adapt and do a small patch test first to be on the safe side.