| HS Code | 660418 |
| Chemical Name | 2,2,4-Trimethylpentane |
| Cas Number | 540-84-1 |
| Molecular Formula | C8H18 |
| Molecular Weight | 114.23 g/mol |
| Grade | Electronic/EL Grade |
| Appearance | Clear colorless liquid |
| Assay Purity | ≥99.9% |
| Density At 20 C | 0.692 g/cm³ |
| Boiling Point | 99.2°C |
| Melting Point | -107.4°C |
| Flash Point | -12°C (closed cup) |
| Refractive Index At 20 C | 1.3915 |
| Water Content | ≤10 ppm |
| Autoignition Temperature | 410°C |
As an accredited Isooctane Electronic/EL Grade factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Packaged in 1-liter amber glass bottles with PTFE-lined caps, sealed under inert gas. Quantity: 1 L. |
| Container Loading (20′ FCL) | 20′ FCL shipment of Isooctane Electronic/EL Grade in palletized drums/IBCs, container sealed for purity, safety, and efficient transport. |
| Shipping | Ship as UN 1262 (Isooctane/Octanes), Class 3 flammable liquid, Packing Group II. Use electrically grounded, approved containers under inert atmosphere to preserve Electronic/EL Grade purity. Protect from moisture, static, heat, and open flames. Ensure secure, labeled packaging per regulations and handle away from ignition sources. |
| Storage | Store Isooctane Electronic/EL Grade in tightly sealed, original containers in a cool, dry, well-ventilated area away from direct sunlight, heat, and ignition sources. Keep separated from oxidizers. Ground containers to prevent static discharge. Ensure proper labeling and secondary containment to avoid leaks. Use spark-proof equipment and maintain inert atmosphere if possible. |
| Shelf Life | Shelf life is typically 24 months from manufacture date if stored unopened, tightly sealed, and away from heat, light, and oxidizers. |
In semiconductor package and leadframe cleaning lines, electronic-grade 2,2,4-trimethylpentane is blended at 15–35 vol% with branched aliphatic or fluorinated co-solvents for removal of plating residues, hydrocarbon oils, and particulate matter from copper, silver-plated copper, and Alloy 42 leadframes before wire bonding. The solvent is applied in multi-stage ultrasonic immersion tools operating at 40 kHz with cascading deionized water rinses at 18 MΩ·cm and a heated nitrogen air knife at 60–80°C. Penetration into narrow wire-bond gaps is supported by a density of 0.692 g/cm³ at 20°C when measured per ASTM D4052 and by surface tension near 18.8 mN/m at 20°C. Water content must remain below 50 mg/kg by Karl Fischer titration per ASTM D6304; higher moisture promotes spot corrosion on silver-plated copper leadframes and increases ionic contamination after drying. Non-volatile residue is controlled to 5 mg/100 mL maximum by ASTM D1353, and production baths are typically replaced when residue reaches 25 mg/100 mL. Post-clean ionic contamination is verified by IPC-TM-650 2.3.25 with acceptance at 1.56 μg NaCl equivalence/cm² or lower, while surface particle counts are measured by a liquid particle counter with 0.5 μm detection. The material must be handled in equipment rated for Class I, Division 1 solvent service because its closed-cup flash point is −12°C per ASTM D56. Polytetrafluoroethylene, perfluoroelastomer, and EPDM wetted parts are acceptable; nitrile rubber and acrylic sight glasses degrade or craze and should not be installed. Table 1 summarizes the typical specification matrix for electronic-grade material used in these cleaning baths.
| Parameter | Test method | Typical control band | Influence on cleaning |
|---|---|---|---|
| Density at 20°C | ASTM D4052 / ISO 12185 | 0.690–0.694 g/cm³ | Affects ultrasonic cavitation intensity and pumping rates. |
| Water content | ASTM D6304 / ASTM E1064 | ≤50 mg/kg | Prevents moisture-driven spot corrosion and residue. |
| Non-volatile residue | ASTM D1353 | ≤5 mg/100 mL | Controls post-evaporation die-attach pad defects. |
| Purity as 2,2,4-trimethylpentane | GC-FID | ≥99.8 area% | Reduces unsaturated hydrocarbon oxidation deposits. |
| Flash point | ASTM D56 / ISO 13736 | −12°C | Dictates Class I electrical area and grounding. |
Blending electronic-grade isooctane with perfluoropolyether or silicone-based lubricants at 2–5 wt% produces a low-viscosity carrier for linear-motion guides and ball screws in semiconductor wafer transfer robots. The mixture is applied by a precision syringe dispenser or by an air-assisted ultrasonic spray nozzle operating at 40 kHz, with carrier evaporation accelerated by clean dry air at 0.2 μm filtration and 30–50°C. The resulting lubricant film is controlled between 0.5 μm and 2.0 μm by white-light interferometry on witness coupons, because heavier films trap particles and lighter films reduce guide-rail load capacity. Electronic-grade material is specified with low non-volatile residue because the carrier must evaporate without leaving hydrocarbon deposits that alter the lubricant boundary lubrication coefficient; the ASTM D1353 residue limit of 5 mg/100 mL is used as the incoming fluid acceptance criterion. Outgassing of the final dry film is checked according to ASTM E595 for vacuum-compatible robot stages; the carrier itself is evaporative and is not part of the tested final film. The solution should not be applied to live electrical contacts, because the flash point of −12°C per ASTM D56 creates a flammable vapor layer under frictional heating. Elastomer seals in the dispense path are best limited to perfluoroelastomer or EPDM; nitrile and natural rubber swell in solvent contact and cause pump leakage.
For laser diode facet and micro-optic cleaning, electronic-grade isooctane is used as a final rinse after aqueous or semi-aqueous cleaning to displace adsorbed water and organic monolayers. AR-coated facets and collimating lenses are immersed in a low-ultrasonic bath at 40 kHz or swabbed with a solvent-saturated polyurethane foam tip, then dried with a 0.2 μm-filtered nitrogen stream at <1.0 bar. Water content is held below 50 mg/kg per ASTM D6304 because hydroxyl groups from moisture can accelerate facet oxidation in AlGaAs laser devices and leave surface defects on fused silica. The low non-volatile residue of the electronic-grade product, tested by ASTM D1353, is critical for optical surfaces where deposits larger than 0.5 μm are visible under dark-field inspection. Bath temperature is maintained below 35°C to limit vapor release; the closed-cup flash point of −12°C per ASTM D56 requires local exhaust and inert grounding. Cleaning efficacy is monitored by water contact angle per ASTM D7334, with a clean fused silica surface typically falling below 10°, and surface roughness can be evaluated by atomic force microscopy on witness wafers to confirm no solvent-induced etching. Published data for specific iso-octane-mediated facet damage thresholds are limited; users should qualify the solvent on cleaved bar test structures before introducing it into production.
Because 2,2,4-trimethylpentane defines the 100 octane number point, high-purity iso-octane is consumed in engine testing, test-fleet calibration, and refinery quality-control laboratories. The ASTM D2699 research octane number and ASTM D2700 motor octane number methods require a reference fuel containing iso-octane and n-heptane blends; electronic-grade iso-octane with an assay of ≥99.8 area% by GC-FID minimizes octane rating drift caused by olefin and aromatic impurities. In laboratory gas chromatography mass spectrometry, electronic-grade iso-octane is used as a diluent for semi-volatile standard mixtures because it elutes early and produces a reproducible mass spectrum with molecular ion m/z 114 and major fragments at m/z 57, m/z 71, and m/z 99; oxygenate interference is low compared with commercial-grade aliphatic solvents. The density of 0.692 g/cm³ at 20°C per ASTM D4052 and the narrow boiling range near 99.3°C per ASTM D86 support reproducible sample preparation for gravimetric dilution. Cleanroom and electronic use of the same grade is governed by the same low-metals and non-volatile residue controls; however, the specification limit of 5 mg/100 mL for non-volatile residue per ASTM D1353 may be more stringent than required for fuel calibration.
In selective spray application of silicone conformal coating on printed circuit assemblies, electronic-grade iso-octane is added at 5–15 wt% to adjust the coating viscosity from above 250 cP to 100–150 cP, as measured by a rotational rheometer with cone-plate geometry at 25°C and 10 s⁻¹. The diluted material passes through 0.3 mm air-atomizing nozzles at 1.2–2.0 bar without spitting or tailing. Because the carrier evaporates in the spray booth before the board reaches the infrared cure oven, the final coating thickness is determined by gravimetric witness coupons and cross-section microscopy with tolerance of ±20 μm. The solvent is selected over lower-purity aliphatic thinners when ionic contamination must remain low; postconformal coat assemblies are tested to IPC-J-STD-001 limits of 1.56 μg NaCl equivalence/cm². The solvent vapor requires continuous lower-explosive-limit monitoring and interlocked exhaust per NFPA 33 or applicable local code, as the closed-cup flash point is −12°C per ASTM D56. This application does not use iso-octane with moisture-cure silicone systems where accelerated hydrolysis of the polymer is possible unless the system is dosed under nitrogen. Production experience shows that batch-to-batch variation in non-volatile residue is the main cause of white haze on boards after cure; incoming material is therefore screened by ASTM D1353 at 5 mg/100 mL maximum.
Electronic-grade iso-octane is used as a post-aqueous rinse for inkjet aperture plates and microfluidic glass capillaries where residual water forms meniscus defects or precipitates buffer salts. The solvent displaces water from 10–50 μm orifices and evaporates from capillary sidewalls under ambient nitrogen airflow. Purity of ≥99.8 area% by GC-FID is necessary because unsaturated impurities can polymerize on heated piezoelectric actuator surfaces and form deposits that alter drop ejection volume. Water content is controlled below 50 mg/kg per ASTM D6304 to prevent drying stains on hydrophilic silicon oxide surfaces. Non-volatile residue is specified at 5 mg/100 mL maximum by ASTM D1353 and can be checked by evaporating a 100 mL sample in a clean PTFE dish at 60°C under filtered airflow. The rinse is not compatible with polycarbonate capillary housings; polypropylene, PTFE, and stainless steel are preferred. Equipment should be grounded, and solvent transfer from drums should be under nitrogen padding to avoid static discharge and prevent moisture ingress. Users have observed reductions in final particle counts when replacing technical-grade aliphatics with electronic-grade iso-octane; published data for this specific configuration is limited, and validation should include optical particle counting at 0.5 μm.
Competitive Isooctane Electronic/EL Grade prices that fit your budget—flexible terms and customized quotes for every order.
For samples, pricing, or more information, please contact us at +8615365186327 or mail to admin@ascent-chem.com.
We will respond to you as soon as possible.
Tel: +8615365186327
Email: admin@ascent-chem.com
Flexible payment, competitive price, premium service - Inquire now!
2,2,4-Trimethylpentane (CAS 540-84-1) is a branched C8 alkane with a molecular formula of C8H18, a molar mass of 114.23 g/mol, a normal boiling point of 99.2 °C, and a closed-cup flash point of −12 °C. The Electronic/EL Grade designation refers to a high-purity solvent class, not to a separate molecular structure; the product is typically supplied as a colorless mobile liquid with a density of 0.692 g/cm³ at 20 °C as measured by ASTM D4052-18a, and with aromatic content below 10 ppm. The grade is used where nonvolatile residue, ionic contamination, and submicronic particles must remain below thresholds that conventional solvent grades do not control.
The Electronic/EL Grade is not defined by a single universal standard; transaction certificates typically combine gas-chromatographic assay, coulometric Karl Fischer moisture, residue-on-evaporation, ICP-MS metals, and particle counts. The values below are representative specification envelopes compiled from publicly available industrial data, not the certification of any single manufacturing site.
| Parameter | Electronic/EL specification | Analytical method or equipment |
|---|---|---|
| Purity | ≥ 99.95% | Capillary GC-FID, 60 m × 0.32 mm dimethylpolysiloxane column, split 150:1 |
| Water | ≤ 20 ppm | ASTM D6304-20, coulometric Karl Fischer |
| Nonvolatile residue | ≤ 2 ppm | ASTM D1353-13, 150 °C nitrogen sweep |
| Particles ≥ 0.2 µm | ≤ 10 particles/mL | Laser particle counter, 0.2 µm and 0.5 µm channels |
| Na, K, Fe, Ca | ≤ 5 ppb each | ICP-MS after 20:1 evaporative preconcentration |
| Chloride | ≤ 1 ppm | Ion chromatography after water extraction |
| Density at 20 °C | 0.692 g/cm³ | ASTM D4052-18a |
| Distillation range | 99.0–99.5 °C | ASTM D86-20b |
For microelectronic use, the limiting parameter is often not bulk hydrocarbon purity but the population of nonvolatile residues and ionic species. A material that passes a GC assay of 99.99% can still be unacceptable if Na, K, Fe, or Ca remains at low-ppb concentrations because these elements redistribute during drying and form defects on wire-bond pads or polyimide passivation layers. Contract manufacturers frequently specify that the summed concentration of Na, K, Fe, Ca, and Zn be ≤ 10 ppb, with no single element above 5 ppb, measured by ICP-MS after evaporative preconcentration in a Class 100 laminar-flow cabinet.
Batch-to-batch particle variance in cleanroom filling lines is often traced to stagnant transfer line segments, especially dead legs longer than 3 pipe diameters. The stagnant solvent can entrain shed polymer fines from filter housings and release them during initial packaging. Qualified distributors typically recirculate the first 10–20 L of packaged product through a 0.1 µm polytetrafluoroethylene cartridge before final particle verification.
Fuel-grade isooctane differs primarily by additive loading, water tolerance, and uncontrolled residue. Material produced for gasoline calibration may contain oxidation inhibitors, detergent packages, and dye markers that are incompatible with electronic cleaning. HPLC-grade material controls water and residue but is not necessarily filtered for particle counts or controlled for cationic metals at the same level. Technical-grade isooctane may allow water above 500 ppm, residue above 10 ppm, and aromatic content above 500 ppm.
| Parameter | Electronic/EL grade | HPLC grade | Technical/fuel grade |
|---|---|---|---|
| Assay | ≥ 99.95% | ≥ 99.0% | not controlled |
| Water | ≤ 20 ppm | ≤ 300 ppm | ≤ 500 ppm |
| Residue after evaporation | ≤ 2 ppm | ≤ 5 ppm | ≤ 10 ppm |
| Particles ≥ 0.2 µm | ≤ 10 particles/mL | not always specified | not specified |
| Cationic metals | ≤ 5 ppb each | not always specified | not specified |
| Packaging | nitrogen-blanketed, fluoropolymer-lined | amber glass or metal | bulk metal |
Production of Electronic/EL Grade isooctane normally starts with alkylate derived from isobutane and butenes over a liquid-acid catalyst. The raw alkylate is caustic washed, water washed, and transferred to a high-efficiency distillation train. The purification column is often operated at a reflux ratio of 5:1 to 15:1, with the heart cut collected over a narrow boiling range of 99.0–99.5 °C. A 40–60 theoretical-plate column separates the target compound from close-boiling C8 isomers and naphthenes; insufficient reflux causes carry-over of 2,2-dimethylhexane and 2,5-dimethylhexane, both of which modify the final residue profile.
Trace water is removed by molecular-sieve adsorption rather than simple distillation. A 3A or 4A molecular-sieve bed operating at ambient temperature and a liquid hourly space velocity of 0.5–1.5 h⁻¹ reduces water below 20 ppm. The bed must be regenerated before breakthrough because water slip causes immediate failure of the Karl Fischer limit. Downstream, 0.05 µm fluoropolymer membrane filtration removes particles; however, filtration after drying can introduce fines if the filter housing is not preflushed with filtered solvent.
A known production conflict occurs between drying and filtration sequence. If the molecular-sieve bed is placed after the membrane filter, molecular-sieve dust enters the final container. If the membrane filter is placed after the molecular-sieve bed, water can desorb from filter housing surfaces and raise moisture by 5–15 ppm in the first 50 L of each batch. Many qualified distributors therefore route material through the molecular-sieve bed first, then a 0.05 µm filter, then a short fluoropolymer static mixer, but they discard the first 10–20 L of filtrate after each filter change.
Because isooctane lacks an oxygen-labile bond, autoxidation and peroxide accumulation are not primary hazards; no stabilizer is required. However, prolonged storage in partially filled containers under air can produce trace polar oxidation products that increase residue. Electronic/EL material is therefore nitrogen-blanketed and stored in fluoropolymer-lined or electrophoretically coated stainless vessels to minimize iron leach. Carbon steel is not used for final packaging because the alkane’s low conductivity permits static discharge and its long storage contact time promotes metal transfer.
In photoresist thinner and edge-bead-remover formulations, isooctane can replace n-heptane when the objective is to reduce surface tension and lower pooling in fine-pitch structures. The measured surface tension of isooctane at 20 °C is approximately 18.8 mN/m, compared with 20.1 mN/m for n-heptane, while the boiling-point difference is less than 1 °C. This combination allows a formulation change without retooling hotplate or exhaust-stack settings. Published data for this specific photoresist-thinner configuration is limited; qualification on actual dispense pumps and coater cups is required before line clearance.
In back-end solvent cleaning of stencils and carrier fixtures, Electronic/EL Grade is used at a controlled draw rate or in a low-humidity glovebox. The high wetting and low residue profile of the neat solvent reduce water residue but make condensation management essential at relative humidity above 60%. Because moisture uptake accelerates in humid rooms, containers should be returned to inert-gas blanketing immediately after decanting.
For immersion stripping of heavy hydrocarbon greases from hybrid-circuit substrates, isooctane is often blended with a low concentration of a polar cosolvent, typically 10–20 vol% of propylene glycol monomethyl ether acetate or isoamyl acetate, to improve solubility of metal carboxylates. The blend is not re-distilled; it is filtered through a 0.2 µm polytetrafluoroethylene capsule immediately before use. The Electronic/EL base reduces the particle burden carried into the blend, but the addition of any cosolvent invalidates the original low-particle classification unless the final blend is re-tested.
Storage beyond 12 months in partially filled containers is not recommended for electronic-grade material because ambient oxygen diffusion through seal interfaces increases nonvolatile residue variability. Containers returned from service are re-sealed with fluoropolymer-faced septa and re-tested for water, residue, and particles before use in a Class 1 cleanroom line. Material that fails the water limit may be re-dried, but material that fails the particle specification cannot be re-qualified by simple filtration without additional batch control.
