Propylene glycol butyl ether (CAS 5131-66-8) — Woody Base Note Fragrance Ingredient
Propylene glycol butyl ether
CAS 5131-66-8
What Is Propylene glycol butyl ether?
Propylene glycol butyl ether is a synthetic organic compound commonly used as a solvent in various household and industrial products. You’ll encounter it in paints, cleaners, and some personal care formulations. It matters because it helps blend ingredients that wouldn’t normally mix, improving product performance while being relatively low in toxicity compared to alternatives.
Safety Profile
USE WITH AWARENESSWhat Does Propylene glycol butyl ether Smell Like?
Propylene glycol butyl ether has a faint, slightly sweet ether-like odor with a clean chemical character. The scent profile remains linear without significant evolution, presenting as a transparent, almost neutral solvent note that can carry other fragrance materials effectively.
In Famous Fragrances
Fragrance associations may not reflect actual formulations.
2D Molecular Structure
SMILES: CCCCOCC(C)O
Chemistry, Properties & Perfumer Guide
The Chemistry
Propylene glycol butyl ether is an organic compound belonging to the glycol ether family, formed by reacting propylene oxide with butanol. These solvents demonstrate both hydrophilic and lipophilic properties due to their ether and alcohol functional groups. Industrial synthesis typically involves acid-catalyzed ring-opening of epoxides.
Physical & Chemical Properties
| Boiling Point | 170-180 °C |
|---|---|
| Density | 0.88 g/cm³ |
| Flash Point | 62 °C |
Perfumer Guide
| Application | Typical % | Range | Notes |
|---|---|---|---|
| Industrial Solvents | 10-30% | Up to 50% | Primary carrier fluid |
| Cleaners | 5-15% | Up to 20% | Degreasing agent |
| Coatings | 8-25% | Up to 40% | Flow control additive |
Classic Accords
Tip: Use as a co-solvent to modify polarity in fragrance systems requiring enhanced solubility of diverse components.
Alternatives & Comparisons
Higher boiling point alternative with similar solvency properties but reduced volatility.
More powerful solvent with increased health concerns requiring careful handling.
Safety, Regulatory & Sustainability
⚠ Regulatory Disclaimer
General reference only. Consult current IFRA Standards Library before formulating.
IFRA Status
Not currently restricted by IFRA standards.
GHS Classification
RIFM Assessment
Not currently evaluated by RIFM as it’s primarily an industrial solvent rather than fragrance material.
Sustainability
Synthesized from petrochemical feedstocks. Considered a VOC in some jurisdictions. Biodegradation studies show moderate environmental persistence. Reformulation opportunities exist using bio-based glycol ether alternatives where performance allows.
Explore Propylene glycol butyl ether
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References
- PubChem Compound Summary for Propylene glycol butyl ether PubChem CID unavailable
Data: PubChem (NIH), PubMed, RIFM, IFRA. Last reviewed: Apr 2026.
Report a data errorPhysicochemical Properties
DTXSID: DTXSID8027589
Physical Properties
| Molecular Weight | 132.203 g/mol🔬 EPA CompTox |
| Density | 0.877 g/cm^3🔬 EPA CTX |
| Boiling Point | 170.96 °C🔬 EPA CTX |
| Melting Point | -46.452 °C📊 OPERA |
| Flash Point | 59.894 °C🔬 EPA CTX |
| Refractive Index | 1.422 Dimensionless📊 OPERA |
| Molar Volume | 148.328 cm^3/mol📊 OPERA |
Partition & Solubility
| LogP (Octanol-Water) | 1.2 Log10 unitless🔬 EPA CTX |
| LogD (pH 5.5) | 1.029 Log10 unitless📊 OPERA |
| LogD (pH 7.4) | 1.029 Log10 unitless📊 OPERA |
| LogKoa (Octanol-Air) | 5 Log10 unitless📊 OPERA |
| Water Solubility | 0.414 mol/L🔬 EPA CTX |
| Henry's Law Constant | 0 atm-m3/mole📊 OPERA |
Transport Properties
| Vapor Pressure | 0.893 mmHg🔬 EPA CTX |
| Viscosity | 4.165 cP📊 OPERA |
| Surface Tension | 27.852 dyn/cm📊 OPERA |
| Thermal Conductivity | 152.563 mW/(m*K)📊 OPERA |
Molecular Descriptors
| Topological Polar Surface Area | 29.46 Ų💻 Computed |
| H-Bond Donors | 1 count💻 Computed |
| H-Bond Acceptors | 2 count💻 Computed |
| Rotatable Bonds | 5 count💻 Computed |
| Aromatic Rings | 0 count💻 Computed |
| Molar Refractivity | 37.718 cm^3/mol📊 OPERA |
| Polarizability | 14.952 Å^3📊 OPERA |
Data Sources:
🔬 EPA Experimental data from U.S. EPA CompTox Chemicals Dashboard & CTX APIs. 📊 OPERA Predicted using EPA's OPERA QSAR models. 💻 Computed Calculated from SMILES using RDKit.
