What Is Bis-Hema Ppg-7/Smdi Copolymer?
Bis-Hema Ppg-7/Smdi Copolymer is a man-made ingredient created by linking together small units of PPG-7 with a form of methylene diphenyl diisocyanate, then finishing the chain with HEMA, a molecule often used in nail products. The result is a long, flexible polymer that acts much like a gentle glue when added to creams, gels or liquids.
The material was developed in the early 2000s as chemists searched for safer alternatives to older adhesive agents that could be harsh on skin. By combining well-known building blocks such as PPG-7 and HEMA, they produced a copolymer that keeps formulas stable without leaving a heavy or sticky feel.
Manufacturing begins with PPG-7, a short chain of propylene glycol, which is reacted under controlled heat with saturated methylene diphenyl diisocyanate. Once the chains reach the right length, HEMA is added to cap the ends and lock the structure in place. After purification and drying, the copolymer is turned into a fine powder or viscous liquid ready for cosmetic use.
You will most often see Bis-Hema Ppg-7/Smdi Copolymer in peel-off masks, long-wear foundations, waterproof eyeliners, nail coatings and certain anti-aging lotions where a flexible film on the skin is desired.
Bis-Hema Ppg-7/Smdi Copolymer’s Cosmetic Benefits/Uses
This ingredient is prized for one main role in beauty formulas.
Binding: Bis-Hema Ppg-7/Smdi Copolymer helps the many parts of a product stick together so pigments, oils and active ingredients stay evenly mixed. On the skin it forms a thin breathable film that boosts wear time, resists smudging and gives products a smooth elegant finish.
Who Can Use Bis-Hema Ppg-7/Smdi Copolymer
Because this copolymer is mostly inert on the skin, it tends to work for normal, dry, oily and combination skin alike. Those with very sensitive or eczema-prone skin can usually tolerate it too, though a small minority who react to acrylate-type materials may notice redness or itching.
Bis-Hema Ppg-7/Smdi Copolymer is fully synthetic and contains no animal derived fragments, so it is considered suitable for both vegans and vegetarians. Cruelty-free status depends on the individual brand’s testing policies.
No studies have linked this ingredient to hormonal issues or fetal development risks. It sits on the surface and is not expected to penetrate in meaningful amounts, so pregnant or breastfeeding women can generally use products containing it. This is not medical advice and anyone who is pregnant or nursing should show new skincare to a doctor to be safe.
The polymer does not make skin more sensitive to sunlight and has no known interaction with common actives like retinol or vitamin C. It can be used morning or night without special precautions.
Potential Side Effects/Adverse Reactions
Reactions to topical Bis-Hema Ppg-7/Smdi Copolymer differ from person to person. The points below list potential side effects but most users will never experience them when the ingredient is formulated and used correctly.
- Mild skin irritation
- Allergic contact dermatitis in individuals already sensitised to acrylate or isocyanate derivatives
- Transient stinging or redness around the eyes if the product is not fully dry before blinking
- Rare clogged pores when very heavy, film-forming formulas are left on overnight without cleansing
- Brittleness or peeling of the nail plate if a nail coating containing the polymer is removed too aggressively
If any of these effects occur stop using the product and consult a healthcare professional.
Comedogenic Rating
Rating: 1/5
Bis-Hema Ppg-7/Smdi Copolymer is a large, surface-sitting molecule that does not slip into pores easily, so it carries a very low tendency to clog them. Formulas that rely on thick waxes or heavy oils alongside this polymer could contribute to congestion, but the copolymer itself is not the culprit. It is therefore generally suitable for acne-prone or breakout-prone skin.
Because the ingredient forms a breathable, flexible film rather than an occlusive seal, it allows normal sebum flow and water vapor escape, which further keeps its comedogenic potential minimal.
Summary
Bis-Hema Ppg-7/Smdi Copolymer acts mainly as a binder and film former, holding pigments, oils and active ingredients together then settling into a thin, invisible layer on skin or nails. This film improves wear time, resists smudging and helps products feel smooth without tackiness.
While not as widely used as older acrylate polymers, it has carved out a spot in long-wear makeup, peel-off masks and certain nail coatings thanks to its gentle feel and reliable performance.
Current data shows it to be low risk for irritation, allergy and pore clogging when used as directed. Still, every skin is unique so it is smart to patch test any new product that features this ingredient before full-face or full-hand application.