1. Basic Identification Information

Parameter	English Specification/Value
IUPAC Name	Methyl 4-hydroxybenzoate
Common Name(s)	Methyl Paraben; Nipagin M; Methyl Parasept; Solbrol M; E218 (EU food additive code)
CAS Registry Number	99-76-3
EC/EINECS Number	202-785-7
Molecular Formula	C₈H₈O₃
Molecular Weight	152.15 g/mol
Chemical Class	Paraben (ester of p-hydroxybenzoic acid and methanol); broad-spectrum antimicrobial preservative

2. Physicochemical Properties

Property Category	Specific Parameter	Specification/Value
Structural Features	Functional Groups	Phenolic hydroxyl (-OH); ester group (-COOCH₃); aromatic benzene ring
Physical Appearance	State & Color	White crystalline powder; odorless or faint phenolic odor
	Melting Point	125–128 °C
	Boiling Point	270–272 °C (decomposes slightly above boiling point)
	Density (25 °C)	1.27 g/cm³ (crystalline form)
Solubility	Polar Solvents	Soluble in ethanol (1 g/3 mL), propylene glycol (1 g/4 mL); moderately soluble in water (0.25 g/100 mL at 25 °C, increases in alkaline systems)