ISOBUTYRIC ACID

Isobutyric Acid is a short-chain branched carboxylic acid used as a chemical intermediate and flavor/fragrance building block, and Isobutyric Acid is known for a strong, sharp, rancid-buttery odor at high concentration.
Isobutyric Acid is widely used in manufacture of esters for flavors and fragrances, in production of specialty chemicals and pharmaceuticals, and as an intermediate for solvents, plasticizers, and additives.
Isobutyric Acid is valued for high reactivity, efficient esterification behavior, and broad industrial utility, but Isobutyric Acid requires careful handling due to corrosivity, strong odor, and flammability risk.

CAS Number: 79-31-2
EC Number: 201-195-7
Molecular Formula: C4H8O2
Molecular Weight: 88.11 g/mol

Synonyms: Isobutyric Acid, 2-Methylpropionic Acid, i-Butyric Acid, Isobutanoic Acid, 2-Methylpropanoic Acid, Isobutyric Acid Reagent, Isobutyric Acid Technical Grade, Isobutyric Acid Flavor Intermediate, Isobutyric Acid Fragrance Intermediate, Branched Butyric Acid, Isobutyric Acid Feedstock, Isobutyric Acid Industrial, Isobutyric Acid, Isobutyric acid, ISOBUTYRIC ACID, 2-Methylpropanoic Acid, 2-Methylpropionic Acid, 2-Methylpropionic acid, 2-Methylpropanoic acid, Isobutanoic Acid, Isobutanoic acid, Isobutyric Acid (IUPAC: 2-Methylpropanoic Acid), 2-Methylpropionic Acid (Isobutyric Acid), 2-Methylpropanoate Acid (common variant), 2-Methylpropanoic Acid (C4H8O2), 2-Methylpropionic Acid (C4H8O2), C4H8O2, Isobutyric Acid (C4H8O2), Isobutyric Acid (CAS 79-31-2), CAS 79-31-2, Isobutyric Acid Anhydrous, Isobutyric Acid Glacial (common trade wording), Isobutyric Acid Solution, Isobutyric Acid Aqueous Solution, Isobutyric Acid 99%, Isobutyric Acid 98%, Isobutyric Acid 95%, Isobutyric Acid Reagent, Isobutyric Acid Analytical Grade, Isobutyric Acid Laboratory Grade, Isobutyric Acid Technical Grade, Isobutyric Acid Industrial Grade, Isobutyric Acid Food Grade, Isobutyric Acid Flavor Grade, Isobutyric Acid Fragrance Grade, Isobutyric Acid Pharmaceutical Grade, Isobutyric Acid USP, Isobutyric Acid EP, Isobutyric Acid BP, Isobutyric Acid FCC, Isobutyric Acid ACS, Isobutyric Acid for Synthesis, Isobutyric Acid for Organic Synthesis, Isobutyric Acid Intermediate, Isobutyric Acid Chemical Intermediate, Isobutyric Acid Manufacturing Intermediate, Isobutyric Acid Esterification Grade, Isobutyric Acid for Esters, Isobutyric Acid for Solvents, Isobutyric Acid for Flavors, Isobutyric Acid for Fragrances, Isobutyric Acid for Polymers, Isobutyric Acid for Resins, Isobutyric Acid for Plasticizers, Isobutyric Acid for Pharmaceuticals, Isobutyric Acid Fermentation Grade, Isobutyric Acid Synthetic, Isobutyric Acid Natural (labeling context), Isobutyric Acid Odorant, Isobutyric Acid Butyric Acid Isomer, Branched Butyric Acid, Iso-Butyric Acid, Iso Butyric Acid, Isobutyrate Acid (common variant), Acidum Isobutyricum, Acide Isobutyrique, Ácido Isobutírico

APPLICATIONS

Isobutyric Acid is used as an intermediate to produce isobutyrate esters for flavor applications with fruity and buttery notes in highly diluted form.
Isobutyric Acid is incorporated into fragrance ester synthesis where sweet, tropical, and fermented fruit accords are targeted.
Isobutyric Acid is used in manufacture of isobutyrate solvents and specialty esters used in coatings and inks.

Isobutyric Acid is used to produce isobutyric anhydride for acylation reactions in chemical synthesis.
Isobutyric Acid is incorporated into organic synthesis as an acyl source for pharmaceuticals and fine chemicals.
Isobutyric Acid is used in preparation of acid chlorides and reactive intermediates for ester and amide formation.

Isobutyric Acid is used in manufacture of cellulose acetate butyrate and related butyrate-modified polymers in some processes.
Isobutyric Acid is incorporated into polymer chemistry to introduce branched aliphatic groups that modify flexibility and solubility.
Isobutyric Acid is used in resin modification routes where controlled acid functionality is required.

Isobutyric Acid is used in production of herbicide and pesticide intermediates where acylation and esterification are key steps.
Isobutyric Acid is incorporated into agrochemical synthesis where branched-chain building blocks are required.
Isobutyric Acid is used in specialty intermediate manufacturing for crop protection chemistry.

Isobutyric Acid is used in pharmaceutical intermediate production where 2-methylpropionyl groups are introduced into target molecules.
Isobutyric Acid is incorporated into synthesis routes to build amides and esters with tuned lipophilicity.
Isobutyric Acid is used in contract manufacturing as a feedstock for diverse specialty chemical projects.

Isobutyric Acid is used in metalworking fluids and industrial formulations where controlled acidity supports performance in compatible systems.
Isobutyric Acid is incorporated into pH adjustment strategies in non-food industrial processes where volatility and odor are managed.
Isobutyric Acid is used in process chemistry where carboxylic acids act as catalysts or reaction modifiers.

Isobutyric Acid is used in production of plasticizer-related intermediates and specialty esters for flexible materials.
Isobutyric Acid is incorporated into additive synthesis where branched structure improves performance traits such as low-temperature behavior.
Isobutyric Acid is used in specialty solvent manufacturing where controlled evaporation and solvency are required.

Isobutyric Acid is used in laboratory chemistry as a reference acid for method development and analytical calibration.
Isobutyric Acid is incorporated into research protocols involving esterification kinetics and reaction optimization.
Isobutyric Acid is used in educational demonstrations of branched-chain carboxylic acid properties and odor behavior.

Isobutyric Acid is used in flavor and fragrance manufacturing to prepare a wide range of isobutyrate esters such as isobutyl isobutyrate and isoamyl isobutyrate.
Isobutyric Acid is incorporated into multi-step synthesis where its branched acyl group contributes to distinctive odor profiles in final esters.
Isobutyric Acid is valued because Isobutyric Acid enables efficient production of branched esters and intermediates across multiple industries.

Isobutyric Acid is used as an intermediate in the manufacture of esters for flavors and fragrances.
Isobutyric Acid is reacted with alcohols to produce fruity-smelling isobutyrate esters.
Isobutyric Acid supports production of aroma ingredients used in food and personal care.

Isobutyric Acid is used in the flavor industry to create buttery, cheesy, and fermented notes in trace amounts.
Isobutyric Acid helps build dairy-like flavor profiles when carefully dosed.
Isobutyric Acid supports formulation of complex savory and snack seasonings.

Isobutyric Acid is used in fragrance compositions to introduce sharp, tangy, and sweaty nuances at low levels.
Isobutyric Acid serves as a starting material for fragrance esters with pleasant odor profiles.
Isobutyric Acid supports perfumery chemistry for both fine fragrance and functional products.

Isobutyric Acid is used as a building block in pharmaceutical and fine chemical synthesis.
Isobutyric Acid participates in acylation reactions to introduce branched-chain acyl groups.
Isobutyric Acid supports preparation of intermediates used in active ingredient manufacturing.

Isobutyric Acid is used in agrochemical synthesis as an intermediate for certain herbicides and pesticides.
Isobutyric Acid supports production of branched-chain derivatives used in crop protection chemistry.
Isobutyric Acid helps provide structural motifs that influence activity and stability.

Isobutyric Acid is used in polymer chemistry to produce specialty monomers and modifiers.
Isobutyric Acid supports synthesis of isobutyrate-functional materials.
Isobutyric Acid helps tailor polymer flexibility and solubility through esterification.

Isobutyric Acid is used in coatings and inks as a precursor to solvent esters.
Isobutyric Acid helps produce esters that adjust drying rate and film formation.
Isobutyric Acid supports formulation of printing inks with tuned evaporation profiles.

Isobutyric Acid is used in cellulose and resin modification to introduce ester functionality.
Isobutyric Acid helps manufacture cellulose isobutyrate-type derivatives in specialty contexts.
Isobutyric Acid supports improved toughness and clarity in certain modified materials.

Isobutyric Acid is used in chemical manufacturing to prepare metal isobutyrate salts.
Isobutyric Acid forms metal carboxylates used as catalysts or driers in some systems.
Isobutyric Acid supports creation of soluble metal soaps for industrial applications.

Isobutyric Acid is used in lubricant additive chemistry as a precursor to ester-based fluids.
Isobutyric Acid contributes branched-chain character that can improve low-temperature behavior.
Isobutyric Acid supports synthesis of esters used in specialty lubrication formulations.

Isobutyric Acid is used in the production of plasticizers and specialty esters.
Isobutyric Acid helps generate esters that improve flexibility of certain polymers.
Isobutyric Acid supports processing and performance enhancement in plastic products.

Isobutyric Acid is used as a reagent in organic synthesis for making acyl chlorides and anhydrides.
Isobutyric Acid supports formation of reactive derivatives used in subsequent coupling steps.
Isobutyric Acid helps enable efficient introduction of isobutyryl groups into molecules.

Isobutyric Acid is used in laboratory synthesis of branched-chain carboxylate derivatives.
Isobutyric Acid supports preparation of reference standards and research intermediates.
Isobutyric Acid helps explore structure–property relationships in branched aliphatic compounds.

Isobutyric Acid is used in microbiology and biochemistry research as a short-chain fatty acid model compound.
Isobutyric Acid supports studies of fermentation pathways and microbial metabolism.
Isobutyric Acid helps evaluate odor and volatile acid formation in cultures.

Isobutyric Acid is used in environmental testing to study volatile fatty acid behavior.
Isobutyric Acid supports research on biodegradation and odor emissions from waste streams.
Isobutyric Acid helps model odor control strategies in treatment facilities.

Isobutyric Acid is used in odorant and malodor testing for product evaluation.
Isobutyric Acid serves as a challenging odor benchmark in deodorization studies.
Isobutyric Acid supports screening of odor absorbers and neutralizers.

Isobutyric Acid is used in formulation research for odor control products such as air fresheners and sprays.
Isobutyric Acid helps test efficacy of cyclodextrins, zinc salts, and other odor binders.
Isobutyric Acid supports controlled sensory panels and instrumental odor measurements.

Isobutyric Acid is used in specialty cleaning research as a model soil for acid odor residues.
Isobutyric Acid supports development of cleaners targeting organic acid malodors.
Isobutyric Acid helps evaluate rinsing and neutralization performance.

Isobutyric Acid is used in animal feed and veterinary research related to volatile fatty acids.
Isobutyric Acid supports studies of rumen fermentation and metabolic indicators.
Isobutyric Acid helps simulate fermentation-derived acids in laboratory assays.

Isobutyric Acid is used in chemical process development to study branched acid esterification kinetics.
Isobutyric Acid supports catalyst screening for esterification and transesterification.
Isobutyric Acid helps optimize reaction conditions for high-purity ester production.

Isobutyric Acid is used in production of isobutyrate esters for solvent use in coatings and cleaners.
Isobutyric Acid helps create esters with good solvency and pleasant odor compared with some alternatives.
Isobutyric Acid supports low-odor solvent design through downstream ester selection.

Isobutyric Acid is used in specialty adhesives as a precursor to resin and ester components.
Isobutyric Acid supports synthesis of tackifiers and modifiers in some formulations.
Isobutyric Acid helps tune viscosity and open time via ester composition.

Isobutyric Acid is used in chemical education laboratories to demonstrate carboxylic acid properties.
Isobutyric Acid supports experiments on acidity, esterification, and odor chemistry.
Isobutyric Acid helps illustrate structure–odor relationships in organic chemistry.

Isobutyric Acid is used as a reference compound in GC and GC-MS method development for volatile acids.
Isobutyric Acid supports calibration and retention index verification in analytical labs.
Isobutyric Acid helps validate sample preparation methods for volatile fatty acids.

Isobutyric Acid is used in food packaging and quality research to study off-odor development.
Isobutyric Acid serves as a marker compound in spoilage and rancidity investigations.
Isobutyric Acid supports evaluation of barrier films and odor scavengers.

Isobutyric Acid is used in fermentation-based chemical production as a target or byproduct monitoring analyte.
Isobutyric Acid supports process control of bioreactors producing volatile fatty acids.
Isobutyric Acid helps track pathway shifts and yield optimization.

Isobutyric Acid is used in sensory science to train panels on rancid and cheesy odor notes.
Isobutyric Acid helps create standardized odor references at controlled concentrations.
Isobutyric Acid supports consistent sensory vocabulary and benchmarking.

Isobutyric Acid is used in synthesis of specialty surfactants and amphiphiles via ester or amide formation.
Isobutyric Acid supports creation of branched hydrophobes that influence micelle behavior.
Isobutyric Acid helps tune foaming, wetting, and solubility in designed surfactants.

Isobutyric Acid is used in research on skin microbiome metabolites related to body odor.
Isobutyric Acid is evaluated as a representative malodor volatile in formulation screening.
Isobutyric Acid supports development of deodorant actives and odor-trapping technologies.

Isobutyric Acid is used in industrial R&D to compare branched versus linear acid derivatives.
Isobutyric Acid supports performance testing of esters in solvency and evaporation studies.
Isobutyric Acid helps identify optimal structures for targeted formulation goals.

Isobutyric Acid is used in specialty chemical manufacturing as a raw material for downstream value-added products.
Isobutyric Acid supports scalable synthesis of esters, amides, and salts.
Isobutyric Acid helps enable diversified product portfolios in fine chemical production.

DESCRIPTION

Isobutyric Acid is typically a colorless liquid with a very strong, penetrating rancid or cheesy odor that becomes pleasant only at extreme dilution in certain ester forms.
Isobutyric Acid is a branched-chain carboxylic acid and is more volatile than many longer-chain fatty acids, which contributes to odor impact and handling considerations.
Isobutyric Acid is miscible with many organic solvents and has limited to moderate miscibility with water depending on temperature and concentration.

Isobutyric Acid readily forms esters with alcohols under acid-catalyzed conditions, and these esters are widely used in flavors, fragrances, and solvents.
Isobutyric Acid reacts with bases to form isobutyrate salts, and these salts can be used in synthesis and specialized applications.
Isobutyric Acid can corrode certain metals and can cause burns, so compatible materials of construction and proper PPE are important.

Isobutyric Acid vapors can irritate the respiratory tract, and odor control with ventilation and closed handling systems is often necessary.
Isobutyric Acid should be stored away from oxidizers and ignition sources because Isobutyric Acid is combustible and can form flammable vapor-air mixtures.
Isobutyric Acid should be stored tightly closed in a cool area to minimize volatilization and to preserve product purity.

Isobutyric Acid is a branched-chain carboxylic acid also known as 2-methylpropionic acid.
Isobutyric Acid is typically a colorless liquid at room temperature.
Isobutyric Acid has a strong, pungent odor often described as rancid or cheesy.

Isobutyric Acid is miscible with many organic solvents and has limited solubility in water.
Isobutyric Acid forms salts with bases to yield isobutyrate compounds.
Isobutyric Acid readily undergoes esterification with alcohols to form isobutyrate esters.

Isobutyric Acid is a weak acid that dissociates partially in aqueous solution.
Isobutyric Acid can be neutralized by alkalis to produce potassium, sodium, or ammonium isobutyrates.
Isobutyric Acid volatility contributes to its strong odor impact even at low concentrations.

Isobutyric Acid is flammable and should be handled away from ignition sources.
Isobutyric Acid can cause irritation to skin, eyes, and respiratory tract depending on exposure.
Isobutyric Acid should be handled with appropriate PPE and good ventilation.

Isobutyric Acid should be stored in tightly closed containers to minimize vapor release and contamination.
Isobutyric Acid should be kept away from strong oxidizers and reactive chemicals.
Isobutyric Acid may attack certain materials, so compatibility testing is recommended for storage and transfer equipment.

Isobutyric Acid is widely used as a chemical intermediate rather than a direct-use consumer ingredient.
Isobutyric Acid is valued for providing branched-chain structure that influences odor and physical properties.
Isobutyric Acid is commonly converted into esters that have much more pleasant fragrance or flavor characteristics.

Isobutyric Acid is used in controlled trace amounts in flavor and fragrance work, where dosing accuracy is essential.
Isobutyric Acid is handled as a specialty chemical requiring careful odor management and waste control.
Isobutyric Acid waste should be disposed of according to regulations for organic acids and flammable liquids.

PROPERTIES

Chemical Formula: C4H8O2
Molecular Weight: 88.11 g/mol
Common Name: Isobutyric Acid (2-Methylpropionic Acid)
Chemical Type: Branched short-chain carboxylic acid
Appearance: Colorless liquid
Odor: Very strong, rancid, cheesy, penetrating odor
Solubility: Moderately soluble in water; miscible with many organic solvents
Boiling Point: ~155–156°C (typical)
Melting Point: ~-47°C (typical)
Density: ~0.95–0.96 g/cm³ (typical)
pKa: ~4.8 (typical)
Vapor Pressure: Moderate (temperature dependent; contributes to odor)
Flash Point: ~43–50°C (typical; method dependent)
Stability: Stable under normal storage; avoid strong oxidizers and strong bases in uncontrolled conditions
Storage Temperature: 15–25°C, tightly closed, away from heat and ignition sources
Shelf Life: Typically 24 months in original sealed packaging (supplier dependent)

FIRST AID

Inhalation:
Move to fresh air immediately if vapors are inhaled.
Seek medical attention if coughing, burning sensation, or breathing difficulty persists.
Keep the person at rest and monitor breathing.

Skin Contact:
Remove contaminated clothing and rinse skin with plenty of water.
Wash with soap and water after thorough rinsing.
Seek medical attention if irritation, burns, or pain develops.

Eye Contact:
Rinse cautiously with water for several minutes and continue rinsing.
Remove contact lenses if present and easy to do, then continue rinsing.
Seek immediate medical attention because eye exposure can be serious.

Ingestion:
Rinse mouth with water and do not induce vomiting.
Seek immediate medical attention, especially if a significant amount is swallowed.
Never give anything by mouth to an unconscious person.

Note to Physicians:
Treat symptomatically and supportively.
Assess for corrosive injury depending on exposure concentration and duration.
Provide airway protection if significant vapor exposure or aspiration risk is suspected.

HANDLING AND STORAGE

Handling:
Use appropriate PPE including acid-resistant gloves, safety goggles, and protective clothing.
Avoid inhalation of vapors and avoid skin contact because Isobutyric Acid can cause irritation and burns.
Use closed transfer systems and odor control measures where feasible.

Ventilation:
Use local exhaust ventilation in areas where vapors may accumulate.
Handle in a well-ventilated area, especially during filling, transfer, and mixing.
Use fume hoods for laboratory-scale work and ensure vapor control in production environments.

Storage:
Store in tightly closed containers in a cool, dry, well-ventilated area.
Keep away from heat, sparks, open flames, and strong oxidizers.
Use corrosion-resistant containers and keep away from incompatible metals when required.

Spill and Leak Procedures:
Contain the spill and prevent entry into drains where not permitted.
Absorb with inert material and neutralize carefully with suitable alkali if trained and permitted.
Collect waste for disposal according to local regulations and facility procedures.

Handling Precautions:
Plan for strong odor management because small leaks can cause significant odor issues.
Ground and bond containers during transfer to reduce static ignition risk.
Rotate stock using FIFO practices and keep containers tightly closed to minimize volatilization and maintain purity.