Triethanolamine

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Abbreviations: TEOA, TEA

Synonyms: 2,2′,2”-Hydroxytriethylamine, Trihydroxyethylamine

Molecular Formula: C₆H₁₅O₃N

Molecular Weight: 149.19

CAS No.: 102-71-6

Structural Formula:

Physicochemical Properties:

A colorless to pale yellow viscous liquid with a faint ammonia-like odor; readily soluble in water and ethanol. It is alkaline, with an aqueous solution pH of approximately 10.5. It can corrode copper, aluminum, and their alloys.

Melting Point: 18–21°C; upon cooling, it can form a supercooled liquid. Relative Density: approx. 1.12. Boiling Point: 190–193°C (at 5 × 133 Pa); decomposes at approximately 335°C under atmospheric pressure. Vapor Pressure: approx. 1.3 Pa. Flash Point: 185°C. Autoignition Temperature: 315°C.

Both the liquid and its vapors are corrosive to the skin and eyes. It reacts with various acids to form esters and amide salts.

It is considered practically non-toxic; acute oral toxicity data for rats indicates an LD₅₀ of 8 g/kg.

Commercially available TEOA products range from high-purity grades (over 99% purity) to grades containing 95%, 90%, 85%, etc., of TEOA; these typically contain water and small amounts of diethanolamine. First-grade products generally possess a purity of ≥98.5% and a moisture content of ≤0.3%.

Characteristics and Applications:

Triethanolamine is a widely utilized chemical raw material. It serves as a vulcanization activator for non-carbon-black-reinforced rubber compounds, an emulsifier for oils and waxes, a coolant for metal cutting, a rust inhibitor, a cement early-strength agent, a neutralizing agent, an absorbent for acidic gases, and a humectant in daily chemical products, among other applications.

In the field of polyurethanes, it functions as an initiator for polyethers, as well as a crosslinking agent and co-catalyst for polyurethane foams and elastomers. Due to the presence of tertiary amine groups, it exhibits catalytic activity; furthermore, it can neutralize acidic components, thereby protecting the primary tertiary amine catalysts present in polyurethane foam formulations.