| HS Code | 232386 |
| Product Name | Boron Ethoxide |
| Iupac Name | Triethoxyborane |
| Common Synonyms | Triethyl borate; Boric acid triethyl ester; Boron triethoxide; Triethoxyboron |
| Cas Number | 150-46-9 |
| Ec Number | 205-760-9 |
| Un Number | 1176 |
| Chemical Formula | C6H15BO3 |
| Molecular Weight | 145.99 g/mol |
| Exact Mass | 146.1114 g/mol |
| Appearance | Colorless clear liquid |
| Odor | Mild, sweet, ether-like |
| Density | 0.864 g/mL at 25 °C |
| Boiling Point | 117-118 °C |
| Melting Point | -84.8 °C |
| Flash Point | 11 °C (closed cup) |
| Refractive Index | n20/D 1.374 |
| Vapor Pressure | 13 hPa at 20 °C |
| Vapor Density | 5.04 (air = 1) |
| Solubility | Decomposes in water; miscible with ethanol, ether, and many organic solvents |
| Water Reactivity | Hydrolyzes in water to form ethanol and boric acid/boric acid derivatives |
| Storage Conditions | Store in a cool, dry, well-ventilated area away from heat and ignition sources; keep container tightly closed and protect from moisture |
| Hazard Classification | Flammable liquid, Category 3 |
| Packing Group | II |
| Moisture Sensitivity | Moisture sensitive |
As an accredited Boron Ethoxide factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Packaged as 100 mL Boron Ethoxide in an amber glass bottle with a PTFE-lined cap, nitrogen-purged and moisture-protected. |
| Container Loading (20′ FCL) | Container Loading (20′ FCL) for Boron Ethoxide: palletized drums, moisture-protected, secured, labeled hazardous, away from ignition sources. |
| Shipping | Boron ethoxide (triethyl borate) is transported as a flammable liquid: UN 2616, Class 3, Packing Group II. Use UN-approved packaging with flammable-liquid labels. Keep cool, dry, and closed, away from ignition sources, oxidizers, acids, and moisture; it hydrolyzes on contact with water. |
| Storage | Store Boron Ethoxide in a cool, dry, well-ventilated, fire-resistant area away from heat, sparks, open flames, oxidizers, acids, and moisture. Keep containers tightly closed under dry nitrogen or argon. Use grounded, explosion-proof equipment, local exhaust ventilation, and secondary containment. Protect from water because it hydrolyzes, releasing ethanol and boric acid. Observe flammable-liquid storage and incompatible-material segregation requirements. |
| Shelf Life | Boron Ethoxide typically has a shelf life of about 12–24 months when stored unopened, cool, dry, and protected from moisture. |
In a two-step sol-gel sequence for borosilicate thin films on float glass, B(OC₂H₅)₃ is pre-hydrolysed in anhydrous ethanol before dosing into a TEOS-based sol. The pre-hydrolysis reactor is a 50 L jacketed glass vessel with a PTFE anchor agitator rotated at 150–200 rpm; the reaction exotherm is controlled by circulating coolant at 10 °C, and the headspace is maintained under nitrogen with a dew point below -40 °C. Water is introduced as a stoichiometric mixture with ethanol at a water-to-alkoxide molar ratio of 0.5 to 1.5 for the boron-containing phase, while the TEOS phase is hydrolysed separately at r=1.5 to 2.0 in the presence of hydrochloric acid at pH 2.0–3.5. Direct co-hydrolysis of B(OC₂H₅)₃ and TEOS in a single vessel causes localised boric acid precipitation and phase-separated gel domains when B₂O₃ exceeds 8 mol%; the resulting films show a visible haze increase from 0.3% to more than 5% measured by ASTM D1003-21. The condensation route B-OH + Si-OH → B-O-Si + H₂O competes with B-OH + B-OH → B-O-B + H₂O, and gel time shifts from more than 72 h at r=0.5 to under 90 min at r=2.0 for the same solvent fraction. The sol is filtered through a 0.1 µm PTFE membrane, cast by spin coating at 1,500–3,000 min⁻¹, and cured in a belt furnace with a 450 °C peak zone for 30 min in air. Cured film adhesion is evaluated by ASTM D3359-17 method B; a 5B classification requires micro-roughened glass rather than mirror-finish float glass. Pencil hardness under ASTM D3363-20 falls between 7H and 9H for a 300–500 nm film. Refractive index at 589 nm moves from 1.45 to 1.48 as B₂O₃ content increases from 5 mol% to 15 mol%. A known production bottleneck is ethanol volatility during open mixing: when relative humidity exceeds 55%, gel point drift of ±20% is observed unless nitrogen blanketing is active. Anhydrous ethanol used as diluent is controlled below 0.05 wt% water by Karl Fischer titration according to ISO 760:1978. Published thickness-versus-spin-speed curves are equipment-specific, and transfer across coating lines requires re-calibration with spectroscopic ellipsometry.
| Property | Test standard | Method or clause | Control window |
|---|---|---|---|
| Cross-cut adhesion | ASTM D3359-17 | Method B | ≥4B; target 5B |
| Pencil hardness | ASTM D3363-20 | Pencil method | ≥7H for 300–500 nm film |
| Haze | ASTM D1003-21 | Procedure A | <1.0% |
| Luminous transmittance | ISO 13468-2:2021 | D65 illuminant | >90% at 550 nm |
| Water content in diluent | ISO 760:1978 | Karl Fischer titration | <0.05 wt% |
Roll-to-roll deposition of boric oxide-containing barrier layers onto 125 µm poly(ethylene terephthalate) web is limited by film stress and water uptake rather than by precursor delivery. B(OC₂H₅)₃ is atomised through an ultrasonic nebulizer operating at 1.8 MHz into a drying tunnel at 60–90 °C; hydrolysis proceeds rapidly in humid air, but the resulting B₂O₃-rich network becomes tacky when B₂O₃ exceeds 12 mol% in the cured film because surface hydroxyls absorb moisture. The process window for haze below 1.0% under ASTM D1003-21 narrows sharply as B₂O₃ is increased from 8 mol% to 15 mol%. Wetting of the hydrolysed precursor on corona-treated PET is checked by contact angle measurement according to ASTM D5946-17; the film spreads uniformly only when the substrate surface energy exceeds 50 mN/m. After coating and drying, the inorganic layer is annealed under a short-wave infrared heater at 120–150 °C for 20–40 s to strip residual ethanol without cracking the web. Cracking of the inorganic layer during mandrel bending is assessed by ISO 1519:2011 using a 10 mm cylindrical mandrel; film failure occurs earlier when B₂O₃ exceeds 10 mol% because the borosilicate network density increases while plastic deformation capacity decreases. Moisture vapour transmission rate of the coated web is measured by ASTM F1249-20 at 38 °C and 90% RH; published values for this specific configuration are limited, but uncoated PET typically remains above 20 g/(m²·day) while inorganic overcoats may reduce transmission by one order of magnitude depending on thickness. Dielectric strength and surface smoothness are monitored with a stylus profilometer; Rₐ values below 2 nm are required for downstream vacuum metallisation. The practical ceiling is governed by hydrolytic instability of B-O-B bonds under tropical humidity: damp heat exposure according to IEC 60068-2-30 for 1,000 h causes visible whitening and adhesion loss when B₂O₃ exceeds 15 mol%. Coating companies therefore restrict B₂O₃ to 5–10 mol% in high-humidity barrier stacks and use an overcoat of plasma-deposited SiO₂ to cap residual borate sites. Published data for specific roll speed and nebulizer flow-rate windows remains limited because the deposition atmosphere is process-specific.
Because B(OC₂H₅)₃ hydrolyses to boric acid under ambient humidity, it functions as a latent diol crosslinker in solvent-borne poly(vinyl alcohol) adhesives that must remain flowable during application and set immediately after moisture contact. In a one-part solution of 4 wt% fully hydrolysed PVA in ethanol/water, addition of B(OC₂H₅)₃ at 0.2–0.5 wt% produces reversible borate-diol junctions; apparent viscosity at 25 °C measured on a cone-plate rheometer at 1 s⁻¹ rises from approximately 2,000 mPa·s to more than 50,000 mPa·s within 120 s after humid air is introduced. Crosslink density is pH-dependent: below pH 6.0, the borate-PVA complex forms only weakly, while above pH 10.0 the borate ester bond hydrolyses too quickly for practical bond strength. The working pH is therefore buffered at 8.0–9.0 with sodium acetate/acetic acid, which stabilises the monodiol-borate chelate and reduces premature gelation in the storage container. Oscillatory shear at 1% strain and 10 rad/s is used to detect the gel transition; the crossover of storage modulus G′ and loss modulus G″ occurs earlier when borate content is increased, and gel time follows an inverse relationship with B(OC₂H₅)₃ concentration. This rheological method is preferred over visual gelation tests because the adhesive is optically opaque and the initial viscosity rise is non-Newtonian. Production dispensing systems use positive-displacement pumps and static mixers rather than spray atomisation because the viscosity increase at the nozzle can exceed the pressure limit of air-atomised equipment. Cleanliness is critical: residual glycols or sorbitol in recycled solvent consume boron species and alter stoichiometry; incoming solvent is specified with a water level below 0.10 wt% by ISO 760:1978. This crosslinking mechanism is also applied in water-soluble temporary masking materials where the dried film must de-bond by soaking at pH 5.0 or below for less than 10 min. Published data for specific PVA degree-of-hydrolysis grades is limited, but the performance boundary is set by the competition between borate-diol crosslinks and hydrogen bonding in the polymer matrix.
Transesterification of B(OC₂H₅)₃ with 3.0–3.5 molar equivalents of 2-propanol or n-butanol is carried out in a glass-lined reactor fitted with a 10-plate Oldershaw column. The reaction equilibrium B(OC₂H₅)₃ + 3 ROH ⇌ B(OR)₃ + 3 C₂H₅OH is shifted by continuous removal of ethanol as an alcohol-ethanol azeotrope; with 2-propanol the overhead temperature is maintained at 80–82 °C at atmospheric pressure. The pot temperature is ramped from 85 °C to 140 °C over 6–8 h while the reflux ratio is held at 5:1. Starting alcohols are dried to a water specification below 0.05 wt% by ISO 760:1978 before charging; water in the feedstock hydrolyses the product into boric acid and consumes starting ester, reducing yield by approximately 1–2% per 0.10 wt% water. Reactor cleanliness is also controlled because residual alkali from cleaning agents accelerates ethanol removal but promotes the formation of high-boiling polyborate residues. The crude borate ester is then fractionated under reduced pressure of 10–20 mbar; collection cuts are made when the vapour temperature stabilises at the value for the target ester at the set pressure, with the exact cut point calibrated by density and refractive index standards. Flame ionisation detection is used for purity: the accepted fraction contains residual ethanol below 0.5 area% and parent borate ester above 99.0 area%. Water ingress during transfer is controlled by loading hot product into dried stainless-steel drums with inert-gas padding. The main operational boundary is azeotrope drift: if overhead temperature deviates by more than ±0.5 K, reflux is increased to 8:1 to restore separation. Higher alcohols such as 2-ethylhexanol require higher pot temperatures but the same stoichiometric principle; production-scale data for branched C₈ transesterification is limited, and laboratory fractionation protocols must be validated against column efficiency.
When B(OC₂H₅)₃ is dosed into a 1.0 M LiPF₆ electrolyte in ethylene carbonate/ethyl methyl carbonate (3:7 vol), the additive acts as a Lewis-acidic moisture and fluoride scavenger rather than as a charge-carrying salt. Formulation work is normally conducted in a dry room with dew point below -50 °C and oxygen below 10 ppm; the finished electrolyte is specified with moisture below 20 ppm by Karl Fischer titration. Additive levels evaluated in published trialkyl borate studies range from 0.5 wt% to 3.0 wt%, with the lower end preferred for high-nickel NMC cathodes because excess borate can reduce anodic stability and increase impedance. Coin-cell cycling in CR2032 hardware with a 20 µm polypropylene separator shows that first-cycle coulombic efficiency can shift by several percentage points depending on formation rate and upper cut-off voltage, but published data for B(OC₂H₅)₃ specifically in full cells is limited. Electrochemical impedance spectroscopy at 10 mHz to 200 kHz is used to separate bulk resistance, SEI resistance, and charge-transfer resistance; changes in SEI resistance are attributed to incorporation of boron-oxygen species in the anode interphase. The operative constraint is the moisture content of the electrolyte and electrode stack: addition of B(OC₂H₅)₃ to a wet electrolyte generates ethanol and boric acid, both of which are problematic for LiPF₆ stability. Storage stability tests at 60 °C for 14 days according to internal battery qualification protocols show acceptable acid-number drift only when the water specification is met. Gas chromatographic monitoring of ethanol in stored electrolyte is used as an indirect marker for hydrolysis; the ethanol peak must remain below 20 ppm after 14 days at 60 °C for the formulation to be considered stable. Batch addition is carried out by metering the borate through a 0.2 µm PTFE filter into the cooled electrolyte at 5–10 °C to avoid local hydrolysis at the additive injection point. If the additive is injected too quickly, local hydrolysis produces boric acid particles that block the 0.2 µm filter and increase upstream pressure. This application is sensitive to container material: borate esters can extract aluminium from uncoated aluminium sampling cans, so borosilicate glass or fluoropolymer-lined vessels are used for storage trials.
As an alternative to liquid-phase sol-gel processing, vapour-phase delivery of B(OC₂H₅)₃ is used to deposit boron-containing oxides in semiconductor thermal reactors. The precursor is held in a temperature-controlled bubbler at 60–80 °C; argon carrier flow is set between 50 sccm and 200 sccm and mixed with oxygen or nitrous oxide downstream. Chamber pressure is maintained at 2–10 Torr, and substrate temperature is controlled between 350 °C and 500 °C. Boron incorporation into the growing oxide network is measured by X-ray photoelectron spectroscopy; published growth-rate data for B(OC₂H₅)₃-based CVD varies with reactor geometry and is insufficient for direct transfer between hot-wall and cold-wall systems. The chief operational boundary is premature decomposition in the heated delivery lines: line temperatures below 90 °C are required to avoid powder formation in the vapour path. Deposited films containing B₂O₃ above 10 mol% show increased sensitivity to standard cleanroom humidity after removal from vacuum, so a post-deposition anneal at 600–700 °C under nitrogen is commonly used to densify the coating and reduce surface hydroxyl density. The bubbler refill procedure uses a minimum of 3 system volumes of dry argon purging before the liquid precursor is charged; particle counts at a 0.3 µm threshold are recorded before and after refilling. Films deposited at the upper temperature boundary show reduced hydrogen content by Fourier-transform infrared spectroscopy, but step coverage in high-aspect-ratio vias is not guaranteed by planar growth-rate data. Published data for patterned via-fill and trench coverage using this precursor is limited, and integration groups validate step coverage by scanning electron microscopy for each reactor geometry.
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Boron ethoxide, also identified as triethyl borate and assigned CAS Registry Number 150-46-9, is commercially supplied as a colorless, moisture-sensitive liquid with the molecular formula B(OC2H5)3 and a molar mass of 145.99 g/mol. Product grades are supplier-specific rather than standardized under a universal model code; the material is specified by CAS number, assay, water content, and trace-metal profile. A widely distributed standard grade is controlled at 98.0–99.0% purity by gas chromatography, and an electronic or deposition grade is controlled at ≥99.9% with sodium, calcium, iron, and copper each below 1 mg/kg by ICP-MS. Physical property data normally reported on certificates of analysis include density of 0.858 g/mL at 25 °C according to ASTM D4052, refractive index n20/D of 1.3730–1.3745, normal boiling point of 117–118 °C, and a closed-cup flash point near 11 °C measured by ASTM D56. The liquid is packaged under dry nitrogen or argon in 500 mL, 1 L, 5 L, and 25 L glass or fluoropolymer-lined stainless steel containers; headspace moisture is commonly maintained below 50 ppm by volume. Unlike tetraethyl orthosilicate, boron ethoxide hydrolyzes rapidly in ambient air, so repeated sampling without a septum-sealed transfer port produces turbidity from boric acid precipitation. Supplier-specific product coding usually appends a purity suffix and packaging size to a base alkoxide code; quotations should therefore reference CAS 150-46-9, required assay, maximum metal ceilings, and container type rather than a single proprietary model designation.
The primary processing boundary is hydrolysis rate. B(OC2H5)3 reacts with water to form boric acid and ethanol; the reaction is sufficiently exothermic that direct addition to neutral water at 25 °C leads to localized condensation to metaboric acid and polyborate clusters instead of a uniform oligomeric sol. In laboratory and pilot-plant reactor practice, the alkoxide is diluted with anhydrous ethanol or 2-methoxyethanol and added to the water-rich phase at 0–5 °C in a jacketed glass reactor fitted with a PTFE or Hastelloy C-276 stirrer operating at 300–600 rpm. Hydrolysis ratios are usually held between 2.0 and 4.0 mol water per mol boron for thin-film sols; ratios above 8.0 produce boric acid crystallization within 24 h at 25 °C. When tetraethyl orthosilicate is co-formulated, the difference in hydrolysis rate requires prehydrolysis of TEOS or the addition of acetylacetone to restrict the free boron coordination sphere. Without that kinetic control, the mixed sol separates during spin coating because boron-rich oligomers condense before a silicate network forms. Viscosity is monitored at 25 °C by ASTM D7042; coating sols tend to fall between 2 and 20 mPa·s. Dynamic light scattering controls particle growth; a translucent sol with Z-average diameter below 10 nm is acceptable for optical coatings, while a visible Tyndall signal above 100 nm indicates premature condensation and the batch is rejected. Sealed sols are commonly stored at 5 °C with a 30 day use window, but at 25 °C viscosity drift can exceed 15% within 7 days. Published data for a specific site reactor configuration is limited, so these limits are validated against the actual cooling jacket, feed rate, and mixing power.
In anhydrous organic media, boron ethoxide functions as a Lewis acid and alkoxide transfer agent. Polyesterification and transesterification reactions use the compound in dried feed streams with water below 100 mg/kg; because it is more moisture-sensitive than titanium tetraisopropoxide, the reactor overhead and receiver must be inerted. Residual ethanol byproduct is removed through a wiped-film evaporator at 80–110 °C and 5–20 mbar; incomplete stripping is associated with haze in the final polymer. The industrial use level is normally determined by sequential addition because the alkoxide is consumed by residual water and free acid before it can act on the carbonyl. In boron-doped carbon fibre or ceramic fibre spinning dopes, coagulation bath pH above 9.0 strips boron as tetrahydroxyborate into the aqueous phase, reducing retained boron in the fibre. This boundary is specific to solution spinning; published formulation data for this configuration is sparse and must be confirmed with inductively coupled plasma analysis of the fibre.
Trimethyl borate has a normal boiling point near 68–69 °C and releases methanol upon hydrolysis; boron ethoxide has a normal boiling point of 117–118 °C and releases ethanol. The lower vapour pressure of the ethyl homolog reduces evaporative cooling during spin coating, which narrows film-thickness variation on 200 mm silicon and fused silica wafers. A typical spin-coating sequence uses a 0.2 µm PTFE syringe filter, a sol containing 5–10 wt% equivalent B2O3, and spin speeds of 2000–4000 rpm for 30–60 s. Prebaking at 120 °C for 5 min removes excess solvent, and annealing at 450 °C in dry air converts the gel to boron oxide. Ellipsometric measurements after densification typically show a refractive index of 1.45–1.48 at 550 nm, with the exact value dependent on residual silanol content in borosilicate films. The replacement of trimethyl borate by the ethoxide is frequently driven by occupational exposure limits: methanol has an OSHA PEL of 200 ppm under 29 CFR 1910.1000 Table Z-1, whereas ethanol has a PEL of 1000 ppm. The methyl homolog remains useful where high vapour pressure is required for low-temperature chemical vapour deposition below 300 °C, because bubble delivery is possible without heating the source. The selection is therefore governed by volatility and byproduct toxicology rather than by a large difference in boron oxide purity.
| Parameter | Boron ethoxide | Trimethyl borate | Tetraethyl orthosilicate | Titanium tetraisopropoxide |
|---|---|---|---|---|
| CAS Registry Number | 150-46-9 | 121-43-7 | 78-10-4 | 546-68-9 |
| Normal boiling point | 117–118 °C | 68–69 °C | 168–169 °C | 232 °C |
| Hydrolysis byproduct | ethanol | methanol | ethanol | isopropanol |
| Hydrolysis behaviour in neutral sol | fast; cooling or chelation required | very fast; cooling required | slow; acid or base catalysis required | fast; β-diketone stabilization required |
| Typical oxide product | B2O3 | B2O3 | SiO2 | TiO2 |
| Principal purity concern | moisture and boric acid haze | moisture and methanol volatility | residual silanol and chloride | alkali residues and particle haze |
Boron ethoxide is also delivered by bubbler or liquid direct injection into low-pressure chemical vapour deposition systems when a chlorine-free boron source is required. The source is maintained at 40–60 °C; chamber pressures of 0.5–5 Torr and substrate temperatures of 350–500 °C are representative for boron oxide or borosilicate glass deposition. Unlike boron trichloride, hydrolysis does not produce hydrogen chloride, and the absence of chlorine reduces corrosion in stainless steel forelines and dry pumps. The alkoxide route, however, carries a carbon contamination risk if pyrolysis is incomplete; the resulting films are therefore characterized by infrared spectroscopy for B–O stretching bands in the 1200–1450 cm−1 region and by X-ray photoelectron spectroscopy for the C 1s signal. In sol-gel glass fabrication, boron ethoxide is used with tetraethyl orthosilicate to produce borosilicate glass compositions with lower thermal expansion than fused silica; the processing difficulty is the rapid hydrolysis of borate species, which can create composition gradients through the film thickness. This gradient is reduced by using low-water hydrolysis ratios and by prehydrolysis of the silicate component. Published data for industrial-scale CVD using boron ethoxide in high-aspect-ratio vias is limited; process qualification requires film composition and step coverage measurements on the actual reactor geometry.
The electronic deposition grade differs from standard chemical grade chiefly in trace-metal and moisture ceilings. Inductively coupled plasma mass spectrometry by ASTM E2371 is used to quantify alkali, alkaline-earth, and transition-metal contamination; volatilized boron oxide films intended for dielectric or passivation layers are sensitive to mobile-ion drift from sodium and potassium. The specification table lists representative commercial ranges rather than a single industry standard, because suppliers do not operate under one unified boron ethoxide monograph. For semiconductor-related work, the lower trace-metal grade is used and the material is drawn only under ultrapure argon with low-moisture regulators. Any container that has been opened for more than one transfer is treated as potentially hydrolyzed unless verified by Karl Fischer titration and turbidity measurement.
| Parameter | Standard grade | Electronic grade | Test method |
|---|---|---|---|
| Assay | 98.0–99.0% | ≥99.9% | gas chromatography |
| Density at 25 °C | 0.856–0.860 g/mL | 0.858 g/mL | ASTM D4052 |
| Refractive index | 1.3730–1.3745 | 1.3730–1.3745 | ASTM D1218 |
| Water | ≤0.5% | ≤100 mg/kg | ASTM E1064 Karl Fischer |
| Chloride | ≤20 mg/kg | ≤1 mg/kg | ion chromatography |
| Sodium | ≤5 mg/kg | ≤0.5 mg/kg | ASTM E2371 ICP-MS |
| Iron | ≤5 mg/kg | ≤0.5 mg/kg | ASTM E2371 ICP-MS |
Direct compounding of boron ethoxide into polymer melts is less common than boric acid or zinc borate addition. The alkoxide evolves ethanol upon exposure to residual moisture in the polymer, and a corotating twin-screw extruder with L/D 40:1 must be vented under nitrogen; otherwise pellet porosity and odour in the finished compound are observed. Boron retention in the polymer must be confirmed by ash digestion and ICP-OES because some boron may volatilize as the alkoxide or hydrolyze at vent ports. Published data for specific thermoplastic formulations is limited; preliminary extrusion trials should compare the alkoxide to boric acid at equivalent boron loadings to determine whether the ethanol release is acceptable for the line.
Transfer and storage operations require the same precautions as low-flash flammable liquids. The closed-cup flash point near 11 °C places the material in a highly flammable category; vapours can travel to ignition sources, so bonding and grounding are mandatory. Boron ethoxide is incompatible with strong aqueous bases above pH 10, strong oxidizing agents, and primary amines; bases convert the compound to borate salts, and amines can form adducts or displace the alkoxide to produce insoluble products. Spills are absorbed with dry, non-combustible material and hydrolyzed in controlled neutral water before disposal. Waste streams must be analyzed for boron and ethanol content; published data on recovery and disposal behaviour of electronic-grade boron ethoxide in semiconductor waste systems is limited, and site-specific profiles are required by 40 CFR 261 characterization. Personal protective equipment includes butyl rubber gloves, face shield, and flame-resistant clothing; local exhaust ventilation is required because hydrolysis releases ethanol vapour.
