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Send EmailPropylene Glycol n-Butyl Ether, 3-Butoxypropan-2-ol, PNB, PGBE, 5131-66-8
Product Name: Propylene Glycol n-Butyl Ether (PNB)
Chemical Name: 1-Butoxypropan-2-ol
CAS No: 5131-66-8
EC No (EINECS): 225-878-4
Chemical Formula: C₇H₁₆O₂
Molecular Weight: 132.20 g/mol
REACH Status: Registered
| Parameter | Description |
|---|---|
| Chemical Name (IUPAC) | 1-Butoxypropan-2-ol |
| Other Names | Propylene Glycol n-Butyl Ether, PNB, Propylene Glycol n-Butyl Ether, PGBE, 3-Butoxypropan-2-ol, Dowanol® PnB |
| CAS Number | 5131-66-8 |
| EC Number (EINECS) | 225-878-4 |
| Molecular Formula | C₇H₁₆O₂ |
| Molecular Weight | 132.20 g/mol |
| Chemical Class | Glycol ether, alcohol-ether, secondary alcohol |
| Appearance | Colorless liquid |
| Odor | Mild ethereal |
| Taste | Not determined as technical product |
| REACH Status | Registered |
CHEMICAL STRUCTURE AND DESCRIPTION:
Propylene Glycol n-Butyl Ether (PNB) is a glycol ether. Its structure contains both an ether (-O-) group and a hydroxyl (-OH) group. It also contains an n-butyl chain. This structure gives PNB both hydrophilic (water-loving) and lipophilic (oil-loving) character. This balance makes it compatible with many polar and non-polar solvents.
Structural Formula (Open Structure):
CH₃-CH₂-CH₂-CH₂-O-CH₂-CH(OH)-CH₃
(1-Butoxypropan-2-ol)
PNB is generally found as a mixture of isomers. Commercial PNB is the n-butyl ether of propylene glycol, with the main component being 1-butoxy-2-propanol. The isomers arise from different modes of attachment of the propylene oxide chain.
These structural features:
Give PNB excellent solvent properties.
Provide miscibility with water and organic solvents.
Offer moderate volatility and a controlled evaporation profile.
Find wide use in coatings, cleaners, and chemical formulations.
PNB is a glycol ether solvent with moderate volatility and excellent solvency for both polar and non-polar substances. It is widely used in paints, inks, varnishes, cleaning products, agricultural chemicals, and electronic cleaning solutions.
| Property | Value |
|---|---|
| Molecular Formula | C₇H₁₆O₂ |
| Molecular Weight | 132.20 g/mol |
| Appearance | Colorless liquid |
| Odor | Mild ethereal |
| Density | 0.88 g/cm³ (20 °C) |
| Boiling Point | ~171 °C |
| Flash Point | 63–65 °C (closed cup) |
| Vapor Pressure | 0.35 kPa (20 °C) |
| Viscosity | ~2.5 mPa·s (20 °C) |
| Surface Tension | ~27 mN/m (20 °C) |
| Refractive Index | ~1.41 (20 °C) |
| Solubility | Miscible with water, compatible with organic solvents |
| Stability | Stable under recommended storage conditions |
| pH (aqueous solution) | Near neutral |
| Volatility | Moderate |
| Hygroscopicity | May absorb slight moisture; store in dry conditions |
PNB is a colorless liquid. Its boiling point is ~171 °C. Its flash point is 63–65 °C (closed cup). Its density is about 0.88 g/cm³. Its vapor pressure is 0.35 kPa at 20 °C. It is miscible with water and most organic solvents. It has moderate volatility and offers a controlled evaporation profile.
| Solvent | Solubility | Conditions |
|---|---|---|
| Water | Miscible | 20 °C |
| Methanol | Miscible | - |
| Ethanol | Miscible | - |
| Isopropanol | Miscible | - |
| Acetone | Miscible | - |
| Ethyl acetate | Miscible | - |
| Hexane | Limited / partially soluble | - |
| Toluene | Miscible | - |
| Xylene | Miscible | - |
| Glycols | Miscible | - |
PNB is miscible with a wide range of polar and non-polar solvents. It is completely miscible with water. This property makes it useful in both water-based and solvent-based formulations.
| Property | Description |
|---|---|
| Chemical Class | Glycol ether, secondary alcohol |
| Reactivity | Esterification, transesterification, urethane formation, etherification |
| Hydrolytic Stability | High |
| Thermal Stability | Good |
| Oxidation Resistance | Moderate |
| Polymerization | Does not undergo hazardous spontaneous polymerization |
| Compatibility | Carboxylic acids, anhydrides, isocyanates, esters |
| Substances to Avoid | Strong oxidizing agents, strong acids, strong bases |
| Hazardous Decomposition Products | Carbon monoxide (CO), carbon dioxide (CO₂), aldehydes, and organic vapors |
Thanks to the hydroxyl group in its structure, PNB can undergo esterification, transesterification, and urethane formation reactions. The ether group enhances its solvent properties. PNB is generally used as a solvent; however, it can also participate in reactions as a chemical intermediate.
| Parameter | Specification |
|---|---|
| Purity (GC) | ≥ 99.0% |
| Appearance | Colorless liquid |
| Color (Pt-Co) | ≤ 10 Hazen |
| Water Content | ≤ 0.1% |
| Acid Value | ≤ 0.01 mg KOH/g |
| Density (20 °C) | 0.875–0.885 g/cm³ |
| Boiling Range | 168–174 °C |
| Flash Point | ≥ 63 °C |
| Refractive Index (20 °C) | 1.405–1.415 |
| Viscosity (20 °C) | 2.0–3.0 mPa·s |
| Heavy Metals | ≤ 10 ppm |
| Shelf Life | 24 months (under proper storage) |
PNB is produced in technical grade with high purity. In industrial applications, batch-to-batch consistency, color stability, and low impurity content are important. High purity is particularly preferred in coating, cleaning, and electronic applications.
| Application | Description |
|---|---|
| Industrial Cleaners | Dissolves oils, dirt, and residues |
| Household Cleaners | Used as a solvent in surface cleaners |
| Metal Cleaners | Dissolves oils and dirt on metal surfaces |
| Surface Preparation | Surface cleaning before painting and coating |
Thanks to its strong solvency power and miscibility with water, PNB is an effective solvent in cleaning products.
| Application | Description |
|---|---|
| Water-Based Paints | Acts as a coalescent solvent, improving film formation |
| Solvent-Based Paints | Solvent and viscosity modifier |
| Varnishes | Improves gloss and surface quality |
| Industrial Coatings | Solvent and flow modifier |
PNB is a widely used solvent in water-based and solvent-based coatings.
| Application | Description |
|---|---|
| Inks | Solvent and viscosity modifier |
| Adhesives | Solvent and adhesion promoter |
| Printing Inks | Solvent and flow modifier |
PNB is used as a solvent in ink and adhesive formulations.
| Application | Description |
|---|---|
| Metal Cleaners | Dissolves oil, rust, and residues |
| Surface Preparation | Surface cleaning before painting |
| Industrial Maintenance | Cleaning of machinery and equipment |
PNB is used as a solvent in metal cleaners and surface preparation processes.
| Application | Description |
|---|---|
| Electronic Cleaners | Used in photoresist and semiconductor cleaning |
| Agricultural Chemicals | Used as a carrier solvent |
| Cosmetics | Used as a solvent in some cosmetic products |
| Property | Description |
|---|---|
| Structural Class | Glycol ether, secondary alcohol |
| Functional Groups | Ether (-O-) and hydroxyl (-OH) |
| Amphiphilic Character | Both hydrophilic and lipophilic |
| Solvency Power | High |
| Evaporation Profile | Moderate, controlled |
| Water Miscibility | Completely miscible |
| Polarity | Medium polarity |
| Polymer Contribution | Solvent, coalescent, viscosity modifier |
The amphiphilic structure of PNB makes it effective in both water-based and solvent-based systems. The ether group increases solvency power, while the hydroxyl group provides miscibility with water. The n-butyl chain enhances lipophilic character.
| Application | Description |
|---|---|
| Coalescent Solvent | Improves film formation in water-based paints |
| Solvent Formulation | Used as a solvent in cleaners and coatings |
| Extraction | Solvent in chemical extraction processes |
| Reaction Medium | Provides solvent medium in chemical reactions |
| Cleaning | Used in industrial and electronic cleaning |
| Carrier Solvent | Carrier in pesticide and agricultural chemicals |
| Parameter | Value |
|---|---|
| GHS Classification | Flam. Liq. 3 (H226), Skin Irrit. 2 (H315), Eye Irrit. 2A (H319), STOT SE 3 (H336) |
| Oral LD50 (Rat) | > 5000 mg/kg |
| Dermal LD50 (Rabbit) | > 5000 mg/kg |
| Skin Irritation | Causes skin irritation (H315) |
| Eye Irritation | Causes serious eye irritation (H319) |
| Respiratory Irritation | Vapor inhalation may cause drowsiness or dizziness (H336) |
| Skin Sensitization | Not expected |
| Mutagenicity | Not classified |
| Carcinogenicity | Not classified |
| Bioaccumulation | Not likely |
| WGK Germany | 1 (slightly hazardous to water) |
PNB is a chemical with low toxicity. It may cause irritation on contact with eyes and skin. Vapor inhalation may cause drowsiness or dizziness. Prolonged and repeated skin contact should be avoided. It is classified as a flammable liquid.
| Parameter | Information |
|---|---|
| UN Number | UN 1993 (Flammable liquid, n.o.s.) |
| Hazard Class | 3 (Flammable liquids) |
| Packing Group | III |
| Proper Shipping Name | Flammable liquid, n.o.s. (Propylene Glycol n-Butyl Ether) |
| Marine Pollutant | No |
| ADR/RID Label | Class 3 |
| Transport Regulations | Must be transported in accordance with ADR/RID/IMDG/IATA rules |
PNB is classified as a flammable liquid. Transport by sea, land, or air must comply with ADR/RID/IMDG/IATA regulations.
| Region | Status |
|---|---|
| EU | REACH registered |
| USA (TSCA) | Listed |
| EINECS | 225-878-4 |
| Turkey (KKDİK) | Should be evaluated within compliance and registration requirements |
| Food Contact | Not suitable for technical grade; special grade required for food contact |
| Hazardous Substance | Yes (flammable liquid) |
| Parameter | Information |
|---|---|
| Storage Conditions | Store in a cool, dry, well-ventilated area |
| Temperature | 15–25 °C |
| Container Requirements | Closed containers, away from moisture and heat sources |
| Moisture Control | Dry environment to prevent moisture absorption |
| Substances to Avoid | Strong oxidizing agents, direct sunlight, ignition sources |
| Shelf Life | 24 months (under proper storage) |
| Handling Notes | Avoid breathing vapor; use PPE |
| Packaging Options | 200 L steel drums, IBC tanks, bulk delivery; custom packaging upon request |
Handling Notes:
Avoid breathing vapor.
Use appropriate personal protective equipment (gloves, goggles, mask).
Avoid contact with skin and eyes.
Keep away from ignition sources.
| Parameter | Information |
|---|---|
| Fire Hazard | Flammable liquid; vapor/air mixture may be flammable |
| Flash Point | 63–65 °C (closed cup) |
| Extinguishing Media | Water spray, foam, CO₂, dry chemical powder |
| Special Hazards | Thermal decomposition may release CO, CO₂, and organic vapors |
| Protective Equipment | Self-contained breathing apparatus (SCBA), full protective clothing |
PNB is a flammable liquid. In case of fire, appropriate extinguishing media should be used, and firefighting personnel should wear protective equipment.
| Parameter | Information |
|---|---|
| Personal Protection | Respirator, protective goggles, gloves, protective clothing |
| Ventilation | Ventilate the area |
| Containment | Contain the spill |
| Cleaning Methods | Absorb with inert material; place in suitable disposal container |
| Environmental Precautions | Prevent entry into drains, sewers, and water sources |
| Waste Disposal | Dispose of according to local regulations |
In case of a spill, clean up while preventing vapor formation. Dispose of waste properly. Prevent environmental release.
| Exposure Route | Action |
|---|---|
| Inhalation | Move to fresh air; seek medical attention if symptoms persist |
| Skin Contact | Wash with plenty of water; seek medical attention if irritation persists |
| Eye Contact | Rinse with water for at least 15 minutes; remove contact lenses if present |
| Ingestion | Do not induce vomiting; seek immediate medical attention |
| Raw Material | Description |
|---|---|
| Propylene Oxide | Precursor in PNB synthesis |
| n-Butanol | Used in etherification reaction |
| Propylene Glycol | Intermediate |
| By-Product | Application |
|---|---|
| PNB Esters | Solvent, plasticizer |
| PNB Acetate | Coating and cleaning solvent |
| Polyurethanes | Adhesives, elastomers |
| Resins | Coatings, adhesives |
| Industry | Application Area | Example Use | Suitability |
|---|---|---|---|
| Cleaning | Solvent | Industrial and household cleaners | High |
| Coatings | Solvent, coalescent | Water-based paints, inks | High |
| Ink and Adhesive | Solvent | Printing inks, adhesives | High |
| Metal Cleaning | Solvent | Metal cleaners, surface preparation | High |
| Electronics | Cleaning solvent | Photoresist, semiconductor | Suitable |
| Agriculture | Carrier solvent | Pesticide formulations | Suitable |
PNB can undergo many chemical reactions due to its hydroxyl group:
| Reaction | Description |
|---|---|
| Esterification | Forms esters with carboxylic acids |
| Transesterification | Reacts with esters to perform ester exchange |
| Urethane Formation | Forms polyurethanes with isocyanates |
| Etherification | Can form ether bonds under suitable conditions |
| Acetylation | Forms PNB acetate derivative with acetic acid |
PNB derivatives are widely used in coatings, cleaners, and polymer systems.
| Compound | Description |
|---|---|
| PNB Acetate | Coating and cleaning solvent |
| PNB Esters | Plasticizer and solvent |
| Propylene Glycol | Intermediate in PNB production |
| Propylene Glycol Methyl Ether (PM) | Similar glycol ether solvent |
| Dipropylene Glycol n-Butyl Ether (DPnB) | Similar glycol ether solvent |
| Ethylene Glycol n-Butyl Ether (EB) | Similar glycol ether solvent |
SUMMARY:
Propylene Glycol n-Butyl Ether (PNB) is a colorless glycol ether solvent with the formula C₇H₁₆O₂ and CAS number 5131-66-8. It has moderate volatility and excellent solvency for both polar and non-polar substances. It is miscible with water and most organic solvents. It is widely used in cleaning products, coating and paint solvents, ink and adhesive formulations, metal cleaners, and surface preparation. Thanks to its amphiphilic character, it is effective in a wide range of formulations. It has low toxicity; however, it is classified as a flammable liquid. It should be stored in a cool, dry, and well-ventilated area in tightly closed containers.
Key Properties:
| Property | Value |
|---|---|
| Appearance | Colorless liquid |
| Chemical Formula | C₇H₁₆O₂ |
| Molecular Weight | 132.20 g/mol |
| CAS Number | 5131-66-8 |
| Boiling Point | ~171 °C |
| Flash Point | 63–65 °C (closed cup) |
| Density | 0.88 g/cm³ (20 °C) |
| Vapor Pressure | 0.35 kPa (20 °C) |
| Solubility | Water and most organic solvents |
| Chemical Class | Glycol ether, secondary alcohol |
| Primary Use | Solvent, cleaner, coating solvent |
Main Applications:
| Industry | Applications |
|---|---|
| Cleaning Products | Industrial and household cleaners |
| Coatings | Water-based paints, inks, varnishes |
| Ink and Adhesive | Printing inks, adhesives |
| Metal Cleaning | Metal cleaners, surface preparation |
| Electronics | Photoresist, semiconductor cleaning |
| Agriculture | Pesticide formulations |
Key Safety Points:
FLAMMABLE LIQUID: Flam. Liq. 3 (H226)
SKIN IRRITATION: Skin Irrit. 2 (H315)
EYE IRRITATION: Eye Irrit. 2A (H319)
RESPIRATORY: STOT SE 3 (H336) – drowsiness or dizziness
STORAGE: 15–25 °C, cool, dry, well-ventilated
PPE RECOMMENDED: Gloves, protective goggles, respirator
INCOMPATIBLE: Strong oxidizing agents, ignition sources
CRITICAL WARNINGS:
PNB is a glycol ether containing both an ether and a hydroxyl group. This structure gives it amphiphilic character.
It is miscible with water and most organic solvents, making it useful in a wide range of formulations.
It acts as a coalescent solvent in water-based paints, improving film formation.
It is used as a strong solvent in industrial and household cleaners.
It is effective in metal cleaners and surface preparation processes.
It serves as a solvent in ink and adhesive formulations.
It is a flammable liquid; it should be kept away from ignition sources.
It is classified as a hazardous substance; appropriate PPE should be used in industrial handling.
Vapor inhalation may cause drowsiness or dizziness; good ventilation should be provided.
It should be stored in tightly closed containers to prevent moisture absorption.
Important Statement: This Technical Data Sheet (TDS) is for informational purposes only. The information provided is based on available data and is believed to be accurate. However, the user is solely responsible for determining the suitability of the product for their own specific applications and for complying with all applicable regulations and safety requirements. For complete safety, use, storage, and regulatory compliance information, always refer to the official Safety Data Sheet (SDS/MSDS) provided by the manufacturer/supplier. Users are obligated to test the product in their own processes and applications. All local, national, and international regulations must be followed when working with PNB.