Sodium Polyaspartate

What is Sodium Polyaspartate?

Sodium Polyaspartate is the sodium salt of polyaspartic acid, a water-soluble anionic polymer synthesized from the amino acid L-aspartic acid via thermal polymerization followed by neutralization. This biodegradable polypeptide appears in hair care items such as shampoos and conditioners, and skincare products like moisturizers and serums. It works by depositing a lightweight film on hair shafts or skin surfaces to seal in moisture, decrease inter-fiber friction, and counteract static charges. As a humectant, it binds atmospheric water to maintain hydration levels. Its mild chelating ability helps sequester metal ions, supporting formula stability without altering pH significantly. Valued for environmental compatibility, it breaks down naturally, making it suitable for green formulations in personal care.

Comedogenic Rating 0/5 Low risk of clogging pores
EWG Safety Rating 1 View on EWG →
PubChem View on PubChem →

Roles in Formulation

This ingredient serves the following purposes in cosmetic formulations:

Hair conditioning
Improves softness, shine, and manageability by reducing friction and static; commonly achieved with cationic agents, silicones, oils, or conditioning polymers.
Humectant
Attracts and holds water in the stratum corneum, boosting hydration and plumpness; commonly used in moisturizers, cleansers, and hair conditioners.
Skin conditioning agent
Maintains skin softness, smoothness, and flexibility.

Benefits

Supports hair softness and ease of combing by smoothing cuticles.

Aids skin moisture retention for a smoother feel.

Enhances product texture through film-forming properties.

Who It's For

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

Who May Benefit Who Should Avoid
Those with dry, frizzy hair needing conditioning support.
People with rare allergies to aspartic acid polymers.
Individuals seeking hydration in daily skincare routines.
Those sensitive to anionic conditioning agents.
Users preferring sustainable, biodegradable cosmetic options.
Individuals preferring minimalist formulas without polymers.

Safety Notes

  • Assessed as low hazard in cosmetic safety reviews.
  • Biodegradable with minimal environmental persistence.

Frequently Asked Questions about Sodium Polyaspartate

What does sodium polyaspartate do in cosmetics?

Acts as a humectant and conditioner to retain moisture and smooth hair or skin surfaces.

Is sodium polyaspartate eco-friendly?

Yes, it biodegrades readily, supporting sustainable product formulations.

Safe for daily use on skin?

Generally low risk based on cosmetic safety data, suitable for most.