POLYISOBUTENE

Polyisobutene is a synthetic hydrocarbon polymer produced by polymerization of isobutylene, and Polyisobutene is widely used as a tackifier, viscosity modifier, binder, and film-forming ingredient in lubricants, fuels, adhesives, sealants, and personal care products.
Polyisobutene is valued for chemical inertness, hydrophobicity, flexibility, and strong tack, and Polyisobutene can be supplied in grades ranging from low molecular weight liquids to high molecular weight rubbery solids.
Polyisobutene provides excellent compatibility with many nonpolar oils and waxes, and Polyisobutene helps improve adhesion, stringiness control, and barrier properties in formulations where water resistance is needed.

CAS Number: 9003-27-4
EC Number: 618-391-8 (polymer listing; grade dependent)
Molecular Formula: (C4H8)n
Molecular Weight: Variable (polymer; grade dependent)

Synonyms: Polyisobutene, Polyisobutylene, PIB, Poly(isobutylene), Isobutylene Polymer, Polyisobutene Polymer, Polyisobutylene Resin, Polyisobutene Oil (low MW grades), Polyisobutylene Liquid Polymer, PIB Viscosity Modifier, PIB Tackifier, Polyisobutene Binder,  Polyisobutene, Polyisobutylene, PIB, Poly(isobutene), Poly(isobutylene), Polyisobutene (INCI), Polyisobutylene (INCI), Polyisobutylene polymer, Isobutylene homopolymer, Isobutene homopolymer, Isobutylene polymer, Isobutene polymer, Poly(2-methylpropene), Poly(2-methylpropene) (IUPAC), 2-Methylpropene polymer, 2-Methylpropene homopolymer, Poly(2-methylprop-1-ene), Poly(2-methyl-1-propene), Polyisobutylene rubber (generic), Polyisobutene rubber (generic), Low molecular weight polyisobutene, High molecular weight polyisobutene, Low molecular weight polyisobutylene, High molecular weight polyisobutylene, Polyisobutene oligomer, Polyisobutylene oligomer, Polyisobutene fluid, Polyisobutylene fluid, Polyisobutene oil, Polyisobutylene oil, Polyisobutene viscosity modifier, Polyisobutylene viscosity modifier, Polyisobutene thickener, Polyisobutylene thickener, Polyisobutene binder, Polyisobutylene binder, Polyisobutene film former, Polyisobutylene film former, Polyisobutene emollient, Polyisobutylene emollient, Polyisobutene skin protectant (use context), Polyisobutylene skin protectant (use context), Polyisobutene tackifier, Polyisobutylene tackifier, Polyisobutene adhesive resin (use context), Polyisobutylene adhesive resin (use context), Polyisobutene lubricant base (use context), Polyisobutylene lubricant base (use context), Polyisobutene dispersant carrier (use context), Polyisobutylene dispersant carrier (use context), Polyisobutene plasticizer (use context), Polyisobutylene plasticizer (use context), Polyisobutene hydrophobic polymer, Polyisobutylene hydrophobic polymer, Polyisobutene hydrocarbon polymer, Polyisobutylene hydrocarbon polymer, Polyisobutene synthetic hydrocarbon, Polyisobutylene synthetic hydrocarbon, Polyisobutene low odor grade, Polyisobutylene low odor grade, Polyisobutene cosmetic grade, Polyisobutylene cosmetic grade, Polyisobutene technical grade, Polyisobutylene technical grade, Polyisobutene high purity, Polyisobutylene high purity

APPLICATIONS

Polyisobutene is used in automotive lubricants as a viscosity modifier to improve viscosity index and film strength.
Polyisobutene is incorporated into engine oils to improve thickening efficiency and help reduce oil consumption in compatible systems.
Polyisobutene is used in gear oils and greases to improve tack, adhesion to metal surfaces, and wear protection support.

Polyisobutene is used in fuel additives as a carrier and deposit-control backbone in some detergent additive packages.
Polyisobutene is incorporated into gasoline and diesel additive systems to help keep injectors and intake valves cleaner in compatible chemistries.
Polyisobutene is used as a starting polymer in the manufacture of certain dispersants and succinimide-type additives.

Polyisobutene is used in grease formulations to improve stringiness, tack, and water resistance.
Polyisobutene is incorporated into open-gear lubricants to improve cling and reduce sling-off under high load.
Polyisobutene is used in chain and cable lubricants to improve adhesion and reduce drip.

Polyisobutene is used in pressure-sensitive adhesives to provide tack and cohesive strength in nonpolar adhesive systems.
Polyisobutene is incorporated into hot-melt adhesives to improve flexibility and bonding on low-energy substrates.
Polyisobutene is used in label and tape adhesives to improve peel strength and repositionable tack profiles.

Polyisobutene is used in sealants and caulks to improve flexibility, water resistance, and long-term tack.
Polyisobutene is incorporated into butyl-based sealants to support low gas permeability and durable sealing performance.
Polyisobutene is used in glazing and construction sealants to improve adhesion and movement accommodation.

Polyisobutene is used in chewing gum base as a component that contributes elasticity and chew texture in approved formulations.
Polyisobutene is incorporated into gum bases to improve chew resistance and reduce brittleness.
Polyisobutene is used in food-contact compliant packaging adhesives when appropriate grades and regulatory compliance are met.

Polyisobutene is used in cosmetics and personal care as an emollient, film former, and texture modifier.
Polyisobutene is incorporated into lip gloss and lipsticks to improve shine, cushion, and long-wear feel.
Polyisobutene is used in skin-care balms to improve occlusivity and water resistance with a smooth sensory profile.

Polyisobutene is used in hair styling products to provide tack, hold, and water resistance in waxy styling systems.
Polyisobutene is incorporated into pomades and hair waxes to improve cohesion and reduce crumbling.
Polyisobutene is used in beard styling products to improve spreadability and long-lasting control.

Polyisobutene is used in electrical and insulation compounds to improve moisture barrier properties and flexibility.
Polyisobutene is incorporated into cable filling compounds to reduce water ingress and improve long-term reliability.
Polyisobutene is used in protective coatings and corrosion-prevention films where hydrophobic barrier performance is desired.

Polyisobutene is used in rubber compounding and polymer modification to improve processability and tack in compatible systems.
Polyisobutene is incorporated into masterbatches to improve dispersion of fillers and to reduce dusting.
Polyisobutene is valued because Polyisobutene provides versatile tack, hydrophobic film formation, and broad compatibility with nonpolar systems across industrial and personal care applications.

Polyisobutene is used as a tackifier and viscosity builder in lubricant and grease formulations.
Polyisobutene improves film strength and helps reduce metal-to-metal contact in lubricated systems.
Polyisobutene supports better adherence of lubricants to surfaces under shear and splash conditions.

Polyisobutene is used as a viscosity modifier in engine oils and gear oils in selected formulations.
Polyisobutene helps improve low-temperature flow and maintain viscosity at operating temperatures when designed properly.
Polyisobutene supports stable lubrication performance across a wide temperature range.

Polyisobutene is used in fuel additives to improve deposit control and system cleanliness in some designs.
Polyisobutene supports dispersant and carrier concepts in gasoline additive packages.
Polyisobutene helps deliver functional additives by improving solubility and handling characteristics.

Polyisobutene is used as a base polymer for polyisobutene succinimide dispersants used in lubricants.
Polyisobutene supports synthesis of ashless dispersants for engine oil formulations.
Polyisobutene helps maintain cleanliness by keeping soot and oxidation products suspended.

Polyisobutene is used in metalworking fluids to improve lubricity in cutting and forming operations.
Polyisobutene supports boundary lubrication under high-pressure contact in machining.
Polyisobutene helps reduce tool wear and improves surface finish in metalworking processes.

Polyisobutene is used in industrial chain oils to improve adhesion and reduce fling-off.
Polyisobutene supports better oil retention on fast-moving chains.
Polyisobutene helps improve wear protection in conveyor and drive systems.

Polyisobutene is used in wire rope lubricants to improve water resistance and cling.
Polyisobutene supports corrosion protection by maintaining a continuous protective film.
Polyisobutene helps reduce lubricant wash-off in outdoor and marine exposure.

Polyisobutene is used in adhesive formulations as a tackifier and flexible binder component.
Polyisobutene supports pressure-sensitive adhesion and improves peel strength.
Polyisobutene helps create flexible adhesive films with good aging properties.

Polyisobutene is used in pressure-sensitive tapes and labels to provide tack and cohesion.
Polyisobutene supports stable adhesion on diverse substrates.
Polyisobutene helps improve low-temperature tack performance in adhesive systems.

Polyisobutene is used in hot-melt adhesives as a viscosity and tack modifier in certain systems.
Polyisobutene supports improved wetting of substrates during bonding.
Polyisobutene helps tune open time and set behavior in formulated adhesives.

Polyisobutene is used in sealants and caulks to improve flexibility and water resistance.
Polyisobutene supports long-term elasticity in construction and automotive sealants.
Polyisobutene helps reduce cracking by maintaining polymer flexibility over time.

Polyisobutene is used in butyl rubber compounding as a compatible polymer component.
Polyisobutene supports improved tack and processing in elastomer blends.
Polyisobutene helps improve air and moisture barrier performance in certain rubber systems.

Polyisobutene is used in tire inner liner formulations to enhance impermeability.
Polyisobutene supports reduced air loss and improved tire pressure retention.
Polyisobutene helps improve durability of barrier layers in tire constructions.

Polyisobutene is used in chewing gum base to provide chew texture and elasticity.
Polyisobutene supports consistent chew and improved shelf stability in gum products.
Polyisobutene helps maintain soft chew properties over storage time.

Polyisobutene is used in food-grade coatings and packaging adhesives where compliant grades are used.
Polyisobutene supports flexible, moisture-resistant bonding in packaging structures.
Polyisobutene helps improve seal integrity and adhesion in multilayer packaging.

Polyisobutene is used in personal care products as a film former and emollient with a glossy finish.
Polyisobutene supports non-volatile shine in lip products and hair styling products.
Polyisobutene helps improve slip and reduces tackiness perception when properly balanced.

Polyisobutene is used in lip gloss and lipstick formulations to provide cushion and long-lasting shine.
Polyisobutene supports improved adhesion of pigments and improved payoff.
Polyisobutene helps reduce feathering by forming a flexible film on lips.

Polyisobutene is used in mascara and eye makeup as a binder to improve wear and smudge resistance.
Polyisobutene supports flexible film formation that resists cracking.
Polyisobutene helps improve lash definition and product staying power.

Polyisobutene is used in skin care balms and ointment-like products to provide occlusivity.
Polyisobutene supports barrier feel and reduces transepidermal water loss perception.
Polyisobutene helps improve spread and richness in anhydrous balms.

Polyisobutene is used in hair styling pomades and waxes to provide hold and shine.
Polyisobutene supports pliable styling films that remain flexible.
Polyisobutene helps improve reworkability and reduces flaking in styling products.

Polyisobutene is used in sunscreen and water-resistant cosmetics to improve film integrity.
Polyisobutene supports improved water resistance when used with suitable film-formers.
Polyisobutene helps maintain even appearance and reduces wash-off.

Polyisobutene is used in waterproofing and protective coatings as a hydrophobic binder component.
Polyisobutene supports water repellency and improved durability on substrates.
Polyisobutene helps reduce moisture uptake and protects against corrosion.

Polyisobutene is used in corrosion protection coatings and rust preventatives for metal parts.
Polyisobutene supports a persistent, water-resistant film on stored components.
Polyisobutene helps reduce oxidation by limiting moisture and oxygen contact.

Polyisobutene is used in electrical insulating compounds and cable filling gels.
Polyisobutene supports hydrophobic gels that protect against moisture ingress.
Polyisobutene helps maintain stable dielectric performance by excluding water.

Polyisobutene is used in pipe jointing compounds to improve sealing and long-term pliability.
Polyisobutene supports leak prevention in threaded joints.
Polyisobutene helps maintain seal integrity under vibration and temperature cycling.

Polyisobutene is used in printing inks as a binder component to improve gloss and rub resistance in some systems.
Polyisobutene supports improved transfer and reduced misting in certain ink designs.
Polyisobutene helps improve adhesion of ink films on nonporous substrates.

Polyisobutene is used in asphalt and bitumen modification to improve flexibility and waterproofing.
Polyisobutene supports improved crack resistance at low temperatures.
Polyisobutene helps improve durability of roofing membranes and waterproofing layers.

Polyisobutene is used in self-adhesive roofing tapes and construction membranes for strong tack and seal.
Polyisobutene supports long-term adhesion under outdoor exposure.
Polyisobutene helps maintain flexibility and sealing performance through weather cycles.

Polyisobutene is used in pharmaceutical topical products as an occlusive, adhesive base component in some systems.
Polyisobutene supports skin-protectant films and improved residence time on skin.
Polyisobutene helps maintain consistency and spreadability in ointment bases.

Polyisobutene is used in transdermal patch adhesives to improve tack and cohesive strength.
Polyisobutene supports stable adhesion over extended wear times.
Polyisobutene helps reduce edge lift by maintaining flexible adhesion.

Polyisobutene is used in laboratory formulations as a hydrophobic binder for model adhesive systems.
Polyisobutene supports evaluation of tack, peel, and shear properties in research.
Polyisobutene helps explore polymer molecular weight effects on viscoelastic behavior.

Polyisobutene is used in manufacturing of protective films and wraps to improve cling properties.
Polyisobutene supports cling stretch film performance in packaging.
Polyisobutene helps maintain film-to-film adhesion without aggressive adhesives.

Polyisobutene is used in latex-free medical adhesive concepts where rubber allergen concerns are addressed.
Polyisobutene supports hypoallergenic positioning in some skin-contact products.
Polyisobutene helps reduce sensitization risk compared with natural rubber in certain contexts.

Polyisobutene is used in chemical intermediate production as a precursor for functionalized polyisobutene derivatives.
Polyisobutene supports synthesis of dispersants, surfactants, and specialty polymers.
Polyisobutene helps create reactive PIB succinic anhydride intermediates for additive chemistry.

Polyisobutene is used in research on barrier materials due to low gas permeability characteristics.
Polyisobutene supports development of protective packaging and sealing concepts.
Polyisobutene helps model diffusion resistance in polymer barrier studies.

Polyisobutene is used in formulation R&D to tune viscosity, tack, and film properties across product types.
Polyisobutene supports selection of molecular weight grades tailored to performance targets.
Polyisobutene helps balance stickiness, gloss, and mechanical stability in final products.

Polyisobutene is used in quality control to confirm molecular weight distribution and viscosity specifications.
Polyisobutene supports consistent processing and end-use performance across batches.
Polyisobutene helps ensure predictable behavior in adhesives, lubricants, and personal care products.

Polyisobutene is used in consumer products where water resistance, flexibility, and long-lasting films are valued.
Polyisobutene supports durable, non-volatile film formation in many hydrophobic systems.
Polyisobutene helps maintain performance under humidity, sweat, and wash exposure.

DESCRIPTION

Polyisobutene is a hydrocarbon polymer made by polymerization of isobutylene monomer.
Polyisobutene is typically supplied as a clear to pale, tacky viscous liquid or semi-solid depending on molecular weight.
Polyisobutene is nonpolar, hydrophobic, and insoluble in water.

Polyisobutene has very low glass transition temperature, which contributes to flexibility and tack at room temperature.
Polyisobutene shows excellent water resistance and good chemical resistance to many aqueous environments.
Polyisobutene is compatible with many oils, waxes, and hydrocarbon resins, supporting broad formulation use.

Polyisobutene properties depend strongly on molecular weight and degree of unsaturation.
Polyisobutene low-molecular-weight grades behave like viscous oils, while higher grades behave like rubbery solids.
Polyisobutene can be supplied as highly reactive polyisobutene with terminal double bonds for further functionalization.

Polyisobutene is valued for tack and cohesive balance in pressure-sensitive adhesive systems.
Polyisobutene is widely used as a base polymer for lubricant dispersant chemistry through functionalized derivatives.
Polyisobutene provides strong film forming and cling behavior due to viscoelastic characteristics.

Polyisobutene is generally stable and resistant to hydrolysis because it contains no ester or amide linkages.
Polyisobutene can oxidize slowly at high temperatures, so antioxidants may be used in some systems.
Polyisobutene handling often requires warming for easier pumping and dosing of higher-viscosity grades.

Polyisobutene should be stored in tightly closed containers to minimize contamination and dust pickup.
Polyisobutene is typically low volatility and has low odor, supporting use in consumer products.
Polyisobutene is valued for versatility across lubricants, adhesives, sealants, packaging, and personal care.

Polyisobutene is a saturated hydrocarbon polymer with excellent chemical resistance, and Polyisobutene is generally stable toward water, dilute acids, and many salts due to its nonpolar structure.
Polyisobutene is available in many viscosity and molecular weight grades, and low molecular weight Polyisobutene can behave like a viscous liquid while higher molecular weight Polyisobutene behaves like a rubbery solid.
Polyisobutene provides tack and cohesive strength, and Polyisobutene is frequently used to modify texture, adhesion, and rheology in nonpolar formulations.

Polyisobutene has low volatility and good thermal stability under typical use conditions, but Polyisobutene can degrade at very high temperatures in air, so processing temperatures should be controlled.
Polyisobutene is compatible with many mineral oils, synthetic hydrocarbons, and waxes, and this compatibility supports stable blends and smooth sensory profiles.
Polyisobutene has very low water solubility, so Polyisobutene improves water resistance and barrier properties in coatings, sealants, and cosmetics.

Polyisobutene should be stored in tightly closed containers away from excessive heat to maintain viscosity consistency and to prevent contamination.
Polyisobutene can be slippery if spilled, so spill cleanup should emphasize slip-hazard control and thorough degreasing.
Polyisobutene should be handled with good industrial hygiene practices, and heated Polyisobutene should be managed to avoid fumes and thermal decomposition.

PROPERTIES

Chemical Formula: (C4H8)n
Molecular Weight: Variable (polymer; grade dependent)
Common Name: Polyisobutene (PIB)
Chemical Type: Saturated hydrocarbon polymer
Appearance: Clear to pale liquid (low MW) or translucent rubbery solid (high MW)
Odor: Mild hydrocarbon odor (grade dependent)
Solubility: Insoluble in water; soluble in many nonpolar hydrocarbons; compatible with mineral oils
Viscosity: Wide range depending on molecular weight and grade
Volatility: Very low (typical)
Density: ~0.88–0.92 g/cm³ (typical; grade dependent)
Glass Transition: Very low Tg, contributing flexibility at low temperatures (typical)
Thermal Stability: Good under typical conditions; avoid excessive heat in air
Chemical Resistance: Excellent resistance to water and many aqueous chemicals; nonpolar character
Storage Temperature: 15–30°C, away from heat and direct sunlight
Shelf Life: Typically 24–60 months in original sealed packaging (supplier dependent)

FIRST AID

Inhalation:
Move to fresh air if vapors or mists from heated product are inhaled.
Seek medical attention if respiratory symptoms persist.
Avoid inhalation of fumes during high-temperature processing.

Skin Contact:
Wash with soap and water after contact.
Polyisobutene can be difficult to remove, so use cleansing oils or suitable cleaners if needed.
Seek medical advice if irritation develops or persists.

Eye Contact:
Rinse cautiously with water for several minutes.
Remove contact lenses if present and easy to do, then continue rinsing.
Seek medical attention if irritation persists.

Ingestion:
Rinse mouth with water.
Seek medical attention if discomfort occurs or if a significant amount is swallowed.
Do not induce vomiting unless directed by medical personnel.

Note to Physicians:
Treat symptomatically.
Aspiration risk may exist if low-viscosity grades are ingested.
Provide supportive care based on exposure route and symptoms.

HANDLING AND STORAGE

Handling:
Use appropriate PPE including gloves and safety glasses.
Avoid contact with eyes and prolonged skin contact, especially when handling hot material.
Wash hands after handling and before eating, drinking, or smoking.

Ventilation:
Use general ventilation for room-temperature handling.
Use local exhaust ventilation during heating, blending, or high-temperature processing to control mists and fumes.
Avoid confined areas where vapors from heated material can accumulate.

Storage:
Store in tightly closed containers in a cool, dry place away from excessive heat.
Protect from contamination and keep containers properly labeled.
Avoid strong oxidizers and keep away from open flames during heated processing.

Spill and Leak Procedures:
Contain spills to prevent spreading and eliminate slip hazards immediately.
Absorb with inert material and collect into suitable containers for disposal according to local regulations.
Clean surfaces thoroughly with detergent or degreaser to remove oily residues.

Handling Precautions:
Control processing temperature to reduce fume formation and prevent thermal degradation.
Select Polyisobutene grade by viscosity and molecular weight to achieve the desired tack, feel, and rheology.
Rotate stock using FIFO practices to maintain consistent viscosity and predictable formulation performance.