Polyglyceryl-2 dipolyhydroxystearate: properties, uses, pros, cons, safety

Polyglyceryl-2 Dipolyhydroxystearate – a lipophilic ester based on polyglycerin and derivatives of 12-hydroxystearic acid (a “bridge” structure between the oil phase and polar microdomains)

Synonyms: polyglyceryl-2 dipolyhydroxystearate (spelling variant); PG2 DPHS (technical/abbreviated use)
INCI / Functions: skin conditioning (cosmetic database); in practice mainly used as a w/o emulsifier and stabilizer for emulsions and lipid dispersions

Definition

Polyglyceryl-2 Dipolyhydroxystearate is a strongly lipophilic, nonionic surfactant obtained as an ester between a polyglycerin moiety (average “2” units) and a “dipolyhydroxystearate” moiety derived from hydroxylated fatty acids (typically 12-hydroxystearic) that are partially “polymerized/oligomerized.” The practical consequence is an ingredient with high affinity for the oil phase and an ability to organize at the interface, making it particularly suitable for water-in-oil (w/o) systems and for lipid-rich dispersions containing oils and powders.

In formulation, its value is less about “wetting” water and more about structuring and stabilizing the micro-architecture of low- to medium-viscosity w/o emulsions, often with high oil fractions and/or with UV filters, pigments, and typical loads of sunscreens and make-up.

The name describes the structure of the molecule:

• Polyglyceryl-2 indicates a polymeric molecule derived from glycerol, a three-atom alcohol. This component provides emulsifying and stabilizing properties to the compound.
• dipolyhydroxystearate refers to a modified form of stearic acid, a saturated fatty acid. The modification introduces additional hydroxyl groups, enhancing solubility and water-binding capacity.

Raw Materials Used in Production.

Polyglyceryl-2 Dipolyhydroxystearate is a synthetic emulsifier and stabilizer derived from the combination of polyhydroxylated fatty acids (like stearic acid) and polyethoxylated glycerin.

Step-by-step Summary of Industrial Production Process.

• Production of polyethoxylated glycerin through the polymerization of glycerol.
• Reaction of polyethoxylated glycerin with stearic acid or similar fatty acids to form the compound.
• Purification of Polyglyceryl-2 Dipolyhydroxystearate to remove impurities and reaction by-products.
• Quality control to ensure the product meets required standards.

Main uses

Cosmetics.
Used primarily as a w/o emulsifier and co-stabilizer in formulations where an external oil phase is required, water resistance is desired, and a controlled film-forming sensorial profile is targeted. Common applications include:

• sunscreens (protection, after-sun, self-tanners) in w/o architecture or oil-rich systems with higher-molecular-weight oils;

• antiperspirants and deodorants (anhydrous or selected w/o systems), where dispersion stability and management of actives/salts are critical;

• baby care and barrier products, when a more protective external oil phase is desired;

• color cosmetics (foundations, concealers, tinted creams) to stabilize pigment dispersions and improve uniformity/wear.

Skin conditioning agent. It is the mainstay of topical skin treatment as it has the function of restoring, increasing or improving skin tolerance to external factors, including melanocyte tolerance. The most important function of the conditioning agent is to prevent skin dehydration, but the subject is rather complex and involves emollients and humectants that can be added in the formulation.

Used as an emulsifier, viscosity controller, dispersant and stabiliser in creamy oil/water emulsions in skin and hair care products.

In chemical products for oral hygiene, sunscreens.

Identification data and specifications

Chemical-physical properties (indicative)

It is a low-HLB ingredient (predominantly lipophilic behavior), with low affinity for free water and good ability to stabilize systems with a continuous oil phase. In practice:

• it works well with a wide range of oils/esters and can support high oil fractions;

• it helps stabilize systems with powders (pigments, fillers) and lipophilic actives;

• final texture depends strongly on: oil type, presence of waxes/structurants, water/oil ratio, and co-emulsifier use.

Functional role and practical mechanism

In a w/o system, it reduces interfacial tension and creates a more “elastic” and stable interface between dispersed internal water microdroplets and the continuous oil phase. In pigment dispersions, it helps wet and maintain a more uniform distribution in the oil phase, improving physical stability and application performance.

Formulation compatibility

Compatibility should be interpreted mainly in terms of emulsion architecture and the lipid package:

• Oils and esters. Generally compatible with a broad range of cosmetic oils; performance (stability and sensoriality) changes significantly between light oils, low-residue esters, and higher-molecular-weight oils/esters.

• Co-emulsifiers. In many w/o formulas it is used in synergy with co-emulsifiers and structurants to widen the stability window and tune viscosity (especially when dispersed water content is significant or when UV filters/powders are present).

• Electrolytes and hydrophilic actives. In w/o, hydrophilic actives reside in the internal water phase: microphase stability and compatibility with salts become important (risk of “osmotic stress” and long-term instability).

• Process and temperature. Repeatability is often tied to thermal-profile control and shear during emulsification, because microstructure and droplet size are key determinants.

Use guidelines (indicative)

In cosmetic formulation it is typically used as a primary emulsifier or co-emulsifier in w/o systems. The effective percentage depends on: water fraction, oil type, powder/UV-filter load, and target viscosity/wear. In practice, formulators often work in a low-to-mid range and optimize with co-emulsifiers/structurants to achieve target stability and sensoriality.

Quality, grades, and specifications

Key QC aspects include:

• identity consistency (declared INCI and CAS) and grade traceability;

• impurity profile and lot-to-lot repeatability;

• behavior in stress tests (thermal cycles, centrifugation, accelerated shelf-life), especially for w/o systems with high filter/powder load.

Safety, regulatory, and environment

In cosmetics, it is a widely used formulation component. Safety assessment is based on the finished product (use scenario, exposure, application area). Operationally, the most common criticalities are technical (stability, compatibility, process robustness) rather than intrinsic toxicological concerns, while still requiring appropriate control of quality, impurities, and supplier documentation.

At quality-system level, adoption of GMP and, where relevant, a HACCP approach supports repeatability and risk control across the production chain.

Formulation troubleshooting

• Instability (phase separation / bleeding): often linked to an unbalanced water/oil ratio, incomplete emulsifier package, or non-optimized microstructure; adjust co-emulsifier/structurants and process.

• Viscosity off target: driven more by the lipid network (oils, waxes, gellants) than by the emulsifier itself; retune structurants and thermal profile.

• Lumps or non-uniform pigment dispersion: improve wetting and dispersion procedure (premix in oil phase, controlled shear).

• Too “greasy” or too “occlusive” feel: lighten the oil phase with lighter/volatile esters or rebalance film formers and structurants.

Conclusion

Polyglyceryl-2 Dipolyhydroxystearate is a key ingredient for w/o emulsions and complex lipid dispersions, particularly useful in sunscreens and make-up for stability, robustness, and management of high loads (heavier oils, UV filters, pigments). Successful application depends mainly on lipid-package design, synergy with co-emulsifiers/structurants, and process control that defines microstructure and long-term stability.

Mini-glossary

HLB: empirical hydrophilic–lipophilic balance index; low values indicate more lipophilic behavior (useful for w/o).
W/O emulsion: “water in oil” emulsion, with a continuous oil phase and dispersed water droplets.
GMP: Good manufacturing practice; benefit: reduces variability and contamination.
HACCP: Hazard analysis and critical control points; benefit: strengthens prevention and control of critical process points.

Safety datasheet:

GHS Polyglyceryl-2 Dipolyhydroxystearate MSDS.pdf (parchem.com)