polyisobutylene

polymer

Polyisobutylene (PIB) is a synthetic rubber-like polymer known for its exceptional impermeability to gases and moisture, making it uniquely suited for applications requiring airtight or hermetic sealing. It is widely used in tire inner liners, pharmaceutical stoppers, gaskets, and adhesive formulations where barrier properties and low gas permeability are critical. Engineers select PIB over alternatives like natural rubber or butyl rubber when extreme impermeability, chemical inertness, and resistance to aging are required, despite its lower mechanical strength compared to some engineering elastomers.

tire inner linerspharmaceutical closures and stoppersgas barrier seals and gasketsadhesives and sealantsfood packaging filmsmoisture barrier membranes

Compliance & Regulations

?UL 94?Conflict Free?RoHS?REACH?TSCA?Prop 65

Units:

si imperial

Property	Value	Unit	Conditions	Source
Glass Transition Temperature(Tg)	200.4	K	—

Verified Unverified Low confidence (<80%) Link to source

Regulatory Screening

Environmental

Safety & Biocompatibility

RoHS, REACH, and Prop 65 statuses are validated against official substance lists (ECHA SVHC Candidate List, OEHHA Prop 65, RoHS Annex II). Other regulations are estimated from composition and material classification. All screening is a starting point for due diligence — always verify with your supplier before making compliance decisions.

polyisobutylene

Thermal Properties

Regulatory Screening

Environmental

Safety & Biocompatibility