Triethyl borate
Overview
Triethyl borate is an organoboron compound primarily used in industrial and chemical synthesis applications. It is classified as an ester of boric acid and ethanol, featuring a boron atom bonded to three ethoxy groups. The compound is valued for its reactivity as a Lewis acid and its role in facilitating cross-linking reactions. Due to its moisture sensitivity, triethyl borate is typically handled under anhydrous conditions. It is commercially available in various purity grades, with technical-grade (95-98%) and high-purity (>99%) variants being the most common. Industrial buyers should confirm specifications such as water content and residual solvents.
Physical and Chemical Properties
Triethyl borate is a volatile, colorless liquid with a mild ester-like odor. Its low boiling point (118-119°C) and density (0.864 g/cm³) make it suitable for reactions requiring moderate temperatures. The compound hydrolyzes in water, releasing ethanol and boric acid, which necessitates careful storage. As a Lewis acid, it forms complexes with electron donors and participates in transesterification reactions. Its flammability (flash point: 11°C) requires precautions against ignition sources. Compatibility testing is recommended when used with plastics or elastomers due to potential solvent effects.
Main Applications
In the polymer industry, triethyl borate serves as a cross-linking agent for silicones and a flame-retardant additive. It enhances thermal stability in materials like epoxy resins. The electronics sector uses it in sol-gel processes for thin-film coatings and as a dopant in semiconductor manufacturing. Organic synthesis employs it for boron-mediated reactions, such as hydroboration and Suzuki couplings. It also acts as a catalyst in esterification and transesterification. Niche applications include laboratory reagent use and as a precursor for other boron compounds.
Safety and Storage
Triethyl borate poses health risks upon inhalation, skin contact, or ingestion, causing irritation to respiratory tracts and eyes. Proper PPE (gloves, goggles, respirators) and fume hoods are mandatory during handling. Spills should be contained with inert absorbents and disposed of as hazardous waste. Storage requires airtight containers under nitrogen or argon to prevent moisture ingress. Keep away from oxidizers and acids to avoid violent reactions. Regulatory compliance (e.g., OSHA, GHS) mandates hazard labeling and SDS documentation for transport and workplace safety.
B2B Procurement Guide
Industrial buyers should prioritize suppliers with ISO-certified manufacturing and batch-specific COAs (Certificates of Analysis). Key procurement criteria include purity (≥98% for synthesis), packaging (steel drums or septum-sealed bottles), and logistical support for hazardous materials. Bulk purchases (100+ kg) often qualify for tiered pricing. Request samples for QC validation, especially for catalytic applications. Long-term contracts may include inventory management services. Regional regulations (e.g., REACH, TSCA) should be confirmed for international shipments.