China Sees a Rise in Polymer-Ingredient Registrations
Since the implementation of China’s updated cosmetic regulations, polymer-based ingredients have emerged as a strategic focus for many cosmetic and raw material manufacturers. As of November 2023, a total of 26 polymer ingredients have been successfully registered under the “situation 6” category, representing roughly 25% of all new cosmetic ingredients filed to date.The popularity of polymeric ingredients is linked to their shorter filing timelines, minimal testing requirements, and lower safety risks compared to other ingredient types.
What Exactly Are Polymer Ingredients in Cosmetics?
When comparing the definition of polymers in chemical management regulations, it becomes clear that the definition of polymer ingredients in cosmetics is slightly different.
| Regulations on the Registration and Notification Dossiers of New Cosmetic Ingredients Definition of Polymer Ingredients | Common Definitions of Polymers under General Chemical Regulations Definition of Polymer Ingredients | |
| Origin | Chemically synthesized | / |
| Molecular Weight Criteria | The number-average molecular weight (Mn) exceeds 1,000 Daltons. The content of low molecular weight species (i.e., oligomers with molecular weights below 1,000 Da) is less than 10% by weight | Polymers exhibit a molecular weight distribution rather than a discrete molecular weight. Molecules of identical molecular weight must account for less than 50% by weight of the total polymer content. |
| Structural Composition | Comprised of one or more types of repeating units (monomeric units) covalently bonded to form a macromolecular structure | Consists of sequences of one or more types of monomer units. More than 50% by weight of the polymer molecules must contain at least three monomer units, covalently bonded to at least one other monomer unit or reactant. |
| Stability | Chemically and structurally stable under normal conditions (excluding substances with intentionally high biological activity) | / |
An analysis of the new 26 polymer ingredients that have been successfully registered so far shows that these ingredients in cosmetics are often used as:
- Film formers – Enhancing durability, water/oil resistance, and product performance in hair styling, sunscreen, and makeup.
- Hair conditioning agents – Providing moisture retention, shine, and smoothness.
- Moisturizers – Forming semi-occlusive layers to retain moisture in the stratum corneum.
- Thickeners – Improving texture, viscosity, and formulation stability.
Other, less frequent but notable functions include emulsifiers, adhesion promoters, sensory modifiers, and exfoliants.
Registration Requirements: Light Testing, But Not Without Challenges
One major benefit of polymer registration is the reduced toxicological testing. Under China’s Cosmetic Safety Assessment Guidelines (2021), high-molecular-weight polymers may be exempt from systemic toxicity and skin sensitization testing due to their limited skin penetration potential.Still, applicants must complete:
- Physicochemical testing:
- Structural confirmation - NMR, IR, MS, UV
- Molecular weight and distribution -GPC, NMR
- Impurity profiling - including potential residual monomers or solvents
- Toxicological testing:
- Skin and eye irritation/corrosion
- Phototoxicity (only if the polymer absorbs UV)
- Stability considerations:
Although often overlooked, stability data is critical for long-term product safety. Drawing from practices in chemical regulations like China’s MEE Order No.12, companies should consider: - Resistance to heat, light, and oxidation
- Microbial stability
- Degradation potential (especially for low molecular weight breakdown products)
Compliance Tips from REACH24H Experts
To help companies meet compliance, REACH24H recommends that companies consider the following best practices for polymer ingredients registration:
- Ensure eligibility under "situation 6" – Confirm that the material meets the polymer definition set by China’s NMPA.
- Don’t skip the structure verification – Even if toxicity tests are limited, physicochemical profiling is mandatory.
- Consider stability and Low MW impurities – Stability data is not formally required, but can significantly reduce the risk of review delays, especially if low molecular weight impurities are present.
- Prepare a robust dossier – Include detailed information on the synthesis process, monomer origin, and purification methods to facilitate the authority's review.
Final Thoughts
Polymercosmetic ingredients represent a promising and regulatory-friendly route for entering or expanding China's growing cosmetics market- but while the process may seem simpler than for other ingredient types, success still depends on thorough dossier preparation. As China continues to refine its regulatory landscape, staying informed, proactive, and detail-focused will help brands and manufacturers stay ahead of compliance requirements and market demands.Need expert help with your polymer ingredient filing? Contact REACH24H at customer@reach24h.com for full-service support, from eligibility review to dossier preparation and submission.
