1. Chemical Structure and Properties
Molecular Formula: C₁₃H₂₈O₄
Structural Formula:
C₄H₉O[CH₂CH(CH₃)O]₃H
A branched glycol ether composed of three propylene oxide units linked to a butyl ether group.
Physical Properties:
Appearance: Clear, colorless to pale yellow liquid with a mild, sweet odor.
Boiling Point: 265–270°C; Density: 0.95 g/cm³; Vapor Pressure:<0.001 mmHg at 25°C.
Solubility: Miscible with water, alcohols, and most organic solvents; excellent solvency for polar and non-polar substances.
Chemical Properties:
Hydrophilic-Lipophilic Balance (HLB): ~3.8, offering balanced solvency for resins, oils, and waxes.
Thermal Stability: Stable up to 220°C; decomposes above 300°C into aldehydes and carbon oxides.
Hydrolysis Resistance: Resists hydrolysis under neutral and mildly acidic/alkaline conditions.
2. Industrial Applications
Coatings & Inks:
High-Boiling Solvent: Enhances flow and leveling in waterborne and solvent-based coatings.
Coalescing Agent: Improves film formation in latex paints and industrial finishes.
Cleaning Formulations:
Heavy-Duty Degreaser: Removes oils, greases, and adhesives in aerospace and automotive cleaning.
Personal Care:
Emollient & Carrier: Used in creams and lotions for its low irritation and moisturizing properties.
Electronics:
Photoresist Stripping: Cleans residues from semiconductor wafers without damaging substrates.
3. Safety and Toxicology
Health Hazards:
Acute Exposure:
Skin Contact: Mild irritation (rabbit skin LD₅₀: >2,000 mg/kg); no sensitization observed.
Inhalation: Low volatility minimizes risk; TLV-TWA: 10 ppm (recommended).
Ingestion: Low toxicity (oral LD₅₀ rat: >5,000 mg/kg).
Chronic Effects:
Reproductive Toxicity: No teratogenic effects in OECD 414 studies.
Organ Toxicity: No significant hepatotoxicity or nephrotoxicity in subchronic studies.
Protection Measures:
PPE: Nitrile gloves, safety goggles; local exhaust ventilation for high-temperature processing.
Storage: Stable in HDPE containers; store away from strong oxidizers.
4. Environmental and Regulatory Compliance
Environmental Impact:
Aquatic Toxicity: LC₅₀ (fish, 96h): >100 mg/L; EC₅₀ (daphnia): >50 mg/L.
Biodegradability: Moderately biodegradable (OECD 301F: 40–60% in 28 days).
Persistence: Low bioaccumulation potential (log Kow: 2.1).
Regulatory Frameworks:
EU:
REACH: Registered with no SVHC listing; CLP classification Not Hazardous.
USA:
EPA: Exempt from VOC regulations (40 CFR 51.100(s)(1)); TSCA-listed.
China:
GB 13690-2009: Classified as General Chemical (non-hazardous).
Waste Management:
Incinerate in approved facilities; wastewater treatment via activated carbon adsorption.
5. Case Studies and Application Insights
Case 1: Sustainable Automotive Coatings (BASF, 2023):
Application: Replaced 20% of ethylene glycol ethers with TPGBE in waterborne automotive primers.
Result: Reduced VOC emissions by 15% while achieving superior adhesion and corrosion resistance.
Case 2: Precision Cleaning in Semiconductor Manufacturing (Samsung, 2022):
Process: TPGBE-based cleaner removed post-etch residues on 5nm-node wafers with 99.9% efficiency.
Cost Savings: Cut solvent consumption by 25% through closed-loop recycling.
Comparative Analysis:
TPGBE vs. Ethylene Glycol Monobutyl Ether (EGBE):
Pros: Lower toxicity, higher boiling point (270°C vs. 171°C), and better biodegradability.
Cons: Higher viscosity (18 mPa·s vs. 3 mPa·s) limits use in low-viscosity formulations.
Specifications:
Tripropylene Glycol Monobutyl Ether is a clear, high-boiling (≈280 °C), low-volatility solvent (≥99% purity) with mild odor, density ≈0.95 g/cm³, and excellent miscibility in water and organic media.