Emulsifying Squalane, GTCC and IPM in Cosmetic Formulations
Squalane, GTCC, and IPM are widely used cosmetic emollients with different polarity, viscosity, and spreading profiles. A stable formulation requires precise oil-phase balancing and suitable emulsification technology. In many modern creams and serums, combining these oils with an effective lotion emulsifier system can reduce droplet size, improve texture, and maintain stability during storage. Studies on cosmetic emulsions show that droplet sizes below 5 μm and optimized emulsifier ratios can significantly improve physical stability over 3–6 months of accelerated testing.
The performance of a cosmetic emulsion depends heavily on the interaction between the oil phase and the emulsifier interface. Squalane, GTCC, and IPM are not interchangeable because their molecular structures create different behaviors during emulsification.
Squalane is a fully hydrogenated derivative of squalene with excellent oxidative resistance. Its saturated hydrocarbon structure provides high chemical stability, with oxidation resistance significantly higher than unsaturated oils commonly used in cosmetics. Because squalane contains no ester groups and has very low polarity, it produces a smooth, silky skin sensation but requires an emulsifier system capable of stabilizing highly lipophilic droplets.
GTCC (glyceryl tricaprylate/caprate) belongs to the medium-chain triglyceride family. It contains ester bonds that provide moderate polarity compared with squalane. This structure allows GTCC to interact more easily with many nonionic emulsifiers and improves oil spreading behavior. In facial emulsions, GTCC is often selected at concentrations between approximately 5% and 30% depending on the desired sensory profile.
IPM (isopropyl myristate) is a lightweight ester emollient commonly used in sunscreens, makeup removers, and skin-conditioning products. Its low viscosity and fast spreading ability help create a dry-touch feeling. However, because IPM can influence skin penetration properties, many formulations control its concentration within approximately 2%–15% to balance spreading performance and skin comfort.
The different polarity ranges of these oils determine how emulsifiers arrange at the oil-water interface.
Squalane provides long-lasting softness, GTCC improves flexibility in oil-phase design, and IPM enhances spreading speed. Combining these three materials allows formulators to adjust texture without relying on a single oil ingredient.
The oil phase composition directly affects emulsifier selection. Cosmetic emulsifiers are usually selected according to hydrophilic-lipophilic balance (HLB), where higher HLB values generally support oil-in-water systems containing more polar oils, while lower HLB values are suitable for more lipophilic materials.
For a squalane-rich formulation, emulsifiers with stronger oil affinity are usually required because the oil droplets have limited interaction with water. For GTCC and IPM systems, emulsifiers with moderate polarity often provide better interface coverage.
Common emulsifier combinations include:
| Emulsifier type | Typical application | Advantages |
|---|---|---|
| Nonionic emulsifiers | Creams and lotions | Good compatibility and mildness |
| Fatty alcohol + emulsifier blends | Barrier creams | Improves viscosity and texture |
| Alkyl polyglucosides | Natural cosmetic systems | Renewable raw material source |
| Polymer-supported systems | Lightweight emulsions | Improves physical stability |
A widely used approach is combining two or more emulsifiers instead of using one single emulsifier. Research on cosmetic emulsions has shown that mixed emulsifier systems can create stronger interfacial films because different molecules occupy different positions around oil droplets.
The selection of a suitable lotion emulsifier becomes especially important when formulating products containing multiple oils with different polarity levels. The emulsifier must maintain droplet separation while preserving a pleasant skin feel.
After emulsifier selection, the ratio between squalane, GTCC, and IPM determines the sensory properties of the final product.
| Formula direction | Oil-phase design | Expected skin feeling |
|---|---|---|
| Lightweight serum | Higher GTCC, moderate IPM, lower squalane | Fast absorption, less oily finish |
| Daily moisturizer | Balanced ratio of three oils | Smooth texture and moderate richness |
| Barrier cream | Higher squalane content | More protective and soft feeling |
| Sunscreen base | Increased IPM and GTCC | Better spreading of UV filters |
A formulation containing 10% squalane, 10% GTCC, and 5% IPM will behave differently from a system containing 20% squalane, 5% GTCC, and 2% IPM. The first system generally provides a lighter application, while the second produces a richer after-feel.
The next consideration is processing technology because emulsifier performance depends not only on ingredients but also on manufacturing conditions.
During production, oil-soluble ingredients are usually heated together with the emulsifier phase. Many cosmetic emulsions are processed between 65°C and 80°C to melt fatty components and allow uniform mixing. High-shear homogenization then reduces oil droplets and improves dispersion.
Typical processing parameters include:
| Parameter | Common range | Effect |
|---|---|---|
| Homogenization temperature | 65–80°C | Improves phase mixing |
| Homogenization time | 3–15 minutes | Controls droplet reduction |
| Cooling rate | Controlled cooling | Affects viscosity development |
| Oil phase ratio | 10–40% | Determines texture |
Droplet size is an important measurement for evaluating emulsion quality. Many commercial cosmetic emulsions maintain average droplet sizes between 1 and 10 μm, while advanced nanoemulsions can reach below 200 nm. Smaller droplets generally provide improved appearance and reduced separation during storage.
However, particle size alone cannot predict long-term stability. The strength of the interfacial layer surrounding each oil droplet also determines whether droplets remain separated.
A smaller droplet requires sufficient interfacial protection; otherwise, droplets may merge during temperature changes or long storage periods.
Stability testing is usually performed under different environmental conditions. Cosmetic companies commonly evaluate samples under room temperature storage, accelerated aging, freeze-thaw cycles, and centrifugation conditions.
Typical evaluation methods include:
| Test method | Purpose |
|---|---|
| Centrifugation | Detects rapid separation tendency |
| Freeze-thaw cycling | Evaluates temperature resistance |
| Viscosity measurement | Monitors structural changes |
| Microscopy analysis | Observes droplet distribution |
| Accelerated aging | Estimates shelf performance |
A common accelerated stability protocol uses storage at 40°C for 3 months, which can provide information about possible changes during longer storage. During these tests, changes in viscosity, odor, color, and phase separation are monitored.
The compatibility between oil phase and active ingredients also affects formulation design. Squalane has strong compatibility with oil-soluble ingredients such as retinol derivatives, tocopherol, and certain botanical extracts. GTCC provides solvent properties for some cosmetic actives, while IPM improves spreading of ingredients across the skin surface.
In sunscreen formulations, IPM and GTCC are frequently used because they help dissolve organic UV filters and improve application uniformity. In anti-aging products, squalane is often selected because of its stable structure and lightweight sensory characteristics.
The trend toward silicone-free cosmetics has increased interest in combinations of hydrocarbon and ester emollients. Since many consumers prefer lightweight textures without silicone ingredients, formulators increasingly use blends of squalane, GTCC, and IPM to reproduce smooth application characteristics.
From 2015 to 2025, the cosmetic industry has shown increasing interest in biodegradable emulsifiers, naturally derived surfactants, and low-energy emulsification methods. These technologies aim to maintain product stability while reducing formulation complexity.
The design of squalane, GTCC, and IPM emulsions requires balancing chemical properties, processing conditions, and consumer expectations. Selecting the correct oil ratio and emulsifier combination allows manufacturers to create products ranging from light facial lotions to rich barrier creams while maintaining stable appearance and performance throughout the product lifespan.