What Is Bis-C16-20 Isoalkoxy Tmhdi/Peg-90 Copolymer?
Bis-C16-20 Isoalkoxy Tmhdi/Peg-90 Copolymer is a lab-made ingredient created by linking together two main building blocks: PEG-90, a water-loving polymer, and TMHDI, a small molecule often used to add strength to plastics and coatings. After these pieces are joined, the ends are “capped” with a branched alcohol that has 16 to 20 carbon atoms, giving the final material a partly oil-like nature. This blend of water-friendly and oil-friendly parts lets the copolymer sit comfortably in many types of cosmetic formulas.
The ingredient came on the scene in the early 2000s as chemists searched for safer, more stable ways to thicken skincare and haircare products without using heavy waxes or large amounts of salt. Its balanced structure offered a modern answer, so it was quickly adopted by formulators looking to improve texture while keeping products light and pleasant.
Manufacturing starts with the controlled reaction of PEG-90 and TMHDI under carefully monitored heat and pH conditions. Once the desired chain length is reached, the mixture reacts with the long branched alcohol, sealing the ends and locking in performance. Quality checks ensure the finished copolymer is free of unreacted starting materials before it goes into drums for cosmetic companies.
You will usually spot Bis-C16-20 Isoalkoxy Tmhdi/Peg-90 Copolymer in face masks, lightweight moisturizers, anti-aging serums, sunscreens, styling creams and makeup foundations that aim for a smooth non-greasy feel.
Bis-C16-20 Isoalkoxy Tmhdi/Peg-90 Copolymer’s Cosmetic Benefits/Uses
This ingredient serves one main job in cosmetics, but it plays that role well.
Viscosity controlling: The copolymer helps set the thickness of a formula so it spreads easily yet stays where you put it. By fine-tuning flow, it prevents products from running off the skin, keeps pigments evenly suspended in makeup and gives creams a silky glide without heaviness.
Who Can Use Bis-C16-20 Isoalkoxy Tmhdi/Peg-90 Copolymer
This ingredient suits most skin types thanks to its lightweight feel and low likelihood of clogging pores. Oily and combination skin benefit from the non-greasy texture while normal and mildly dry skin enjoy the smooth glide it adds to creams and serums. Extremely dry skin may still crave richer occlusives because the copolymer itself does not lock in moisture the way heavy butters do. It is generally well-tolerated by sensitive skin since it has no added fragrance or active acids that could sting.
Because the copolymer is fully synthetic and made from petroleum-derived building blocks and plant-free alcohols it is considered suitable for both vegans and vegetarians.
No specific warnings exist for pregnancy or breastfeeding. The ingredient is not absorbed through intact skin in meaningful amounts and has no known hormonal activity. That said this is not medical advice and pregnant or nursing women should run any skincare product past their doctor just to be safe.
Bis-C16-20 Isoalkoxy Tmhdi/Peg-90 Copolymer does not cause photosensitivity and it stays stable when exposed to sunlight so there is no special need for extra sun protection beyond daily SPF guidelines.
Potential Side Effects/Adverse Reactions
Reactions to topical Bis-C16-20 Isoalkoxy Tmhdi/Peg-90 Copolymer can vary from person to person. The following list covers potential side effects though most users will not experience them when the ingredient is used correctly in a finished product.
- Mild skin irritation such as temporary redness or itching
- Rare allergic contact dermatitis in individuals sensitive to trace isocyanate residues
- Transient eye irritation if the product accidentally gets into the eyes
- Very slight chance of clogged pores in highly acne-prone skin when used in heavy formulations
If you notice any of these issues stop using the product and consult a healthcare professional or dermatologist.
Comedogenic Rating
Rating: 1 / 5
Bis-C16-20 Isoalkoxy Tmhdi/Peg-90 Copolymer earns a low score because its large, branched structure sits on the skin surface rather than sinking into pores. It adds slip without forming the heavy, oily film that typically traps dead cells and sebum. Most finished formulas use it at small percentages, further lowering any clogging risk. In short, the ingredient is generally friendly for acne-prone and breakout-prone skin.
As with any polymer, the final product’s full recipe matters. If the copolymer is blended with rich plant oils or butters the overall clogging potential can rise, so keep an eye on the whole ingredient list.
Summary
Bis-C16-20 Isoalkoxy Tmhdi/Peg-90 Copolymer is mainly a viscosity controller that fine-tunes thickness, keeps pigments and actives evenly dispersed and gives creams or serums a smooth, lightweight feel. It achieves this by pairing water-loving PEG segments with oil-friendly end caps, letting it bridge watery and oily ingredients and hold them in a stable, silky network.
The copolymer is not a household name and shows up more in niche or premium formulas than in mass-market lines, yet its ability to create elegant textures has earned it a loyal following among cosmetic chemists.
Safety data shows very low irritation and allergy rates, no known hormonal effects and minimal pore-clogging risk at normal use levels. Even so, skin can be unpredictable, so patch test any new product that lists this ingredient to make sure it agrees with you.