1. Chemical Structure and Properties
Molecular Formula: C₆H₁₂O₃
Structural Formula:
CH₃COO–CH₂CH₂–O–CH₂CH₃
A glycol ether ester formed by the acetylation of ethylene glycol monoethyl ether.
Physical Properties:
Appearance: Clear, colorless liquid with a mild ester-like odor.
Boiling Point: 156–158°C; Density: 1.006–1.010 g/cm³; Vapor Pressure: 0.5 mmHg at 20°C.
Solubility: Miscible with most organic solvents (e.g., ethanol, acetone); slightly soluble in water (3% w/w at 25°C).
Chemical Properties:
Hydrolysis Stability: Resistant under neutral conditions; degrades in strong acids/bases to acetic acid and ethylene glycol monoethyl ether.
Thermal Stability: Stable up to 150°C; decomposes above 200°C, releasing acetaldehyde and CO₂.
Flammability: Combustible (flash point: 46°C; autoignition temperature: 235°C).
2. Industrial Applications
Coatings & Inks:
High-Boiling Solvent: Used in automotive paints and industrial coatings for enhanced flow and leveling.
Coalescing Agent: Improves film formation in waterborne latex paints.
Electronics:
Photoresist Stripper: Cleans hardened resists from semiconductor wafers without damaging substrates.
Cleaning Products:
Precision Degreaser: Effective in aerospace and electronics manufacturing for removing oils and fluxes.
Adhesives:
Plasticizer: Enhances flexibility in epoxy and polyurethane adhesives.
3. Safety and Toxicology
Acute Exposure:
Inhalation: Irritates respiratory tract (TLV-TWA: 5 ppm); dizziness and headaches at high concentrations.
Skin Contact: Causes irritation and dermatitis (rabbit skin LD₅₀: >2,000 mg/kg).
Ingestion: Moderately toxic (oral LD₅₀ rat: 2,500 mg/kg); gastrointestinal distress.
Chronic Effects:
Reproductive Toxicity: Linked to developmental toxicity in animal studies (EU CLP: Repr. 1B).
Carcinogenicity: Not classified by IARC; limited evidence of genotoxicity.
Protection Measures:
PPE: Nitrile gloves, vapor respirators, and chemical goggles.
Storage: Store in flame-resistant containers away from oxidizers and heat sources.
4. Environmental and Regulatory Compliance
Environmental Impact:
Biodegradability: Slow (OECD 301F: <30% in 28 days); moderately persistent in soil.
Aquatic Toxicity: LC₅₀ (fish, 96h): 50–100 mg/L; EC₅₀ (daphnia, 48h): 20–50 mg/L.
Bioaccumulation: Low (log Kow: 0.8).
Regulatory Frameworks:
EU:
REACH: Restricted in consumer products (Annex XVII); CLP classified as Flam. Liq. 3 (H226) and Repr. 1B (H360D).
USA:
EPA: Regulated under TSCA; OSHA PEL: 5 ppm (8-hour TWA).
China:
GB 13690-2009: Classified as Hazardous Chemical (Class 3.2).
Waste Management:
Incinerate in licensed facilities with VOC abatement; landfill disposal prohibited.
5. Case Studies and Application Insights
Case 1: Sustainable Automotive Coatings (PPG, 2023):
Challenge: Reduce VOC emissions in waterborne automotive primers.
Solution: Replaced 15% of xylene with EGEAc.
Result: Achieved 25% lower VOC emissions (ASTM D6886) while maintaining adhesion (ASTM D3359).
Case 2: Green Semiconductor Cleaning (Intel, 2022):
Process: Adopted EGEAc in 5nm-node lithography for photoresist stripping.
Impact: Reduced solvent waste by 30% and met SEMI S2-0703 safety standards.
Comparative Analysis:
EGEAc vs. Ethylene Glycol Monobutyl Ether Acetate (EGBEA):
Pros: Lower bioaccumulation potential; better compatibility with polar resins.
Cons: Higher reproductive toxicity and flammability.
EGEAc vs. Propylene Glycol Methyl Ether Acetate (PGMEA):
Pros: Higher boiling point (156°C vs. 146°C); better solvency for acrylics.
Cons: PGMEA offers lower acute toxicity and faster evaporation.
Specifications:
2-Ethoxyethyl acetate is an organic compound with the formula CH3CH2OCH2CH2O2CCH3. It is the ester of ethoxyethanol and acetic acid. A colorless liquid, it is partially soluble in water.