Paint chemicals

Polypropylene Glycol Monomethyl Ether (MPPG): Overview and Key Properties

Category	Details
Chemical Name	Polypropylene glycol monomethyl ether (MPPG)
CAS Number	9003-13-8 (varies by molecular weight)
Molecular Formula	CH₃O[CH₂CH(CH₃)O]ₙH
Appearance	Colorless to pale yellow liquid
Odor	Mild, characteristic

Physical & Chemical Properties

Property	Typical Value
Molecular Weight	300–2.000 g/mol (n=5–30)
Density (20°C)	0.95–1.02 g/cm³
Viscosity (25°C)	50–500 mPa·s
Boiling Point	150–300°C (depends on MW)
Flash Point	80–150°C
Solubility	Water-miscible (low MW); soluble in organic solvents

Key Performance Features

Feature	Advantage
Low Toxicity	Safer alternative to glycol ethers
Hydrophilicity	Effective coupling agent
Thermal Stability	Stable to 200°C

Manufacturing Process

Step	Description
Alkoxylation	Propylene oxide + methanol (base catalyst)
Purification	Neutralization, distillation

Applications

Industry	Function
Coatings	Solvent, flow aid
Inks	Pigment dispersant
Cleaning	Degreasing agent
Pharmaceuticals	Excipient
Electronics	Flux cleaner

Comparison with Similar Glycol Ethers

Property	MPPG	Ethylene Glycol Ethers
Toxicity	Lower	Higher
Biodegradability	Better	Moderate
Hydrophilicity	Adjustable (via MW)	Fixed

Safety & Handling

Parameter	Specification
LD50 (Oral)	>2.000 mg/kg
Skin Irritation	Mild
Storage	Keep sealed, avoid moisture

Market Data

Application	Market Share
Coatings	45%
Industrial Cleaners	30%
Others	25%

Regulatory Status

Region	Compliance
US EPA	VOC-exempt (certain grades)
EU	REACH registered
Japan	MITI approved

Key Advantages and Limitations

Advantages	Limitations
Tunable hydrophilicity	Higher cost than standard solvents
Low environmental impact	Limited high-temperature stability
Broad compatibility	Viscosity increases with MW

Summary

MPPG serves as a versatile, low-toxicity glycol ether with adjustable properties for coatings, cleaning, and pharmaceutical applications. Its molecular weight variability enables tailored performance across industries.