Diethyl Maleate

Diethyl maleate, also known as diethyl *cis*-butenedioate, is the diethyl ester of maleic acid and belongs to the class of unsaturated dicarboxylic acid esters. It appears as a colorless, transparent, oily liquid with a distinctive aromatic odor reminiscent of fruit or wine; it is slightly soluble in water and miscible with various organic solvents such as ethanol, diethyl ether, and benzene.

Send Inquiry

Product Introduction

Zouping Jinxing Chemical Co., Ltd. is one of the leading manufacturers and suppliers of diethyl maleate in China. If you're going to wholesale bulk diethyl maleate made in China, welcome to get free sample from our factory. All customized products are with high quality and low price.

Basic properties

Appearance: Diethyl maleate is a colorless, transparent, oily liquid with a distinctive aromatic odor resembling fruit or wine.
Boiling point: 223–225°C (at atmospheric pressure)
Melting point: -10°C
Density: 1.064 g/cm³ (at 25°C; denser than water)
Flash point: 93°C (closed cup); classified as a combustible liquid
Solubility: Slightly soluble in water; miscible with various organic solvents such as ethanol, diethyl ether, and benzene

Primary Uses

Pesticide and pharmaceutical intermediates: Diethyl maleate is primarily used to produce the organophosphorus insecticide malathion and as a structural unit for certain β-lactam drugs.
Polymer material modification: Used as a comonomer in the preparation of specialty resins; improves the heat resistance and flexibility of unsaturated polyester resins and enhances the hardness of UV-curable materials.
Coatings and additives: Used as a solvent for nitrocellulose and a plasticizer for plastics; also improves coating adhesion and gloss in paint formulations.

Safety and Toxicology

Acute toxicity: Oral LD₅₀ in rats is approximately 3200 mg/kg; Diethyl maleate is classified as having low toxicity..
Irritation and sensitization: Causes mild irritation to the skin and eyes; may induce allergic skin reactions.
Biochemical toxicity mechanism: Acts as a sulfhydryl-reactive substance; depletes intracellular glutathione and interferes with the body's detoxification functions.
Protection requirements: Operations must be conducted in a closed system with adequate ventilation; wear a gas mask, chemical safety goggles, and oil-resistant rubber gloves; keep away from ignition sources and heat, and avoid contact with oxidizing agents, acids, and bases.