Regular Butyl & Halogenated Butyl Rubber

Elastomers used in tire inner liners, tire inner tubes, tire curing bladders, window sealants, damping mounts, hoses, and seals need to have excellent low permeability to gases and moisture, broad damping characteristics, as well good ageing, heat and ozone resistance.

Butyl rubber offers solutions to all these requirements.

ARLANXEO's X_Butyl® rubber is also a material of choice for medical and pharmaceutical stoppers due to its purity, impermeability, and good resealing properties.


Advanced rubber solutions have their place in securing a more sustainable and safe future for the planet. ARLANXEO's research innovation enables our partners in the tire, medical, adhesives and other sectors to provide end-products meeting stringent quality standards and reduce fuel consumption or preserve valuable medications.

Butyl rubber vulcanizates are highly sought after as a result of their impermeability to air and moisture, high damping of low frequency vibrations, and good resistance to ageing, heat, acids, bases, ozone and other chemicals.

Regular butyl rubber (IIR) is a copolymer of isobutylene and a small fraction of isoprene (0.5 – 2.5 mol%). The isoprene is incorporated into the polymer chain to provide unsaturation which permits the rubber to be vulcanized. Due to the nature of this polymer, butyl rubber adopts a densely packed structure that results in excellent impermeability to gases, one of the defining characteristics of this class of polymer.

IIR is used in a wide variety of applications including tire inner tubes, tire curing envelopes and bladders, adhesives, sealants, tank linings and chewing gum.

IIR rubber can also be halogenated in an aliphatic solvent using chlorine (Cl2) or bromine (Br2) to yield chlorobutyl (CIIR) and bromobutyl (BIIR) rubber, respectively. Halogenation allows co-vulcanization and improved compatibility with other diene rubber types, in addition to improvements in the vulcanization rates, states of cure and reversion resistance. Typical applications for halogenated butyl rubber (XIIR) include tire inner liners, hoses, seals, membranes and is often the choice for medical stopper applications due to its cleanliness and good resealing properties. The X_Butyl® product family comprises a broad range of IIR and XIIR products.

The airtight advantage

Given butyl rubber’s excellent air retention, this amorphous rubber is the preferred material for tire inner liners and inner tubes. It's low permeability to gases, moisture and liquids help maintain proper tire pressure, reduces corrosion of steel belting, minimizes the oxidation of other tire components, and ensures consistent performance over time. All this leads to improved efficiency, safety, and longer tire life.

This elastomer’s unique attributes including low permeability and the ability to be vulcanized with clean cure systems enables wide use in non-tire applications such as medical and pharmaceutical rubber products. Those include stoppers for infusion containers, injection vials, and blood collection tubes. Halogenated butyl rubber (XIIR) is generally preferred because it ensures adequate protection, in the form of stoppers and seals, of sterile pharmaceutical products against external contamination during storage, secure delivery, and use.

Another sector with heightened quality control requirements is the food industry. X_Butyl® 101-3 is a certified grade that meets the stringent quality controls, consistent with food regulations and standards. It is the material of choice for the manufacturing of chewing gum base. Since butyl rubber offers outstanding stability and resistance to ageing, stick gum packaged from your favorite brands will not harden during shelf storage — making sure the soft texture will be preserved when you are ready to enjoy it.

Related Topics



X_Butyl® is a synthetic rubber that is impermeable to air and effective for applications requiring airtight rubber properties. It's used in the automotive, food, sports, and medical industries.



Specialty rubbers used in the automotive industry and formulated to maximize the performance of tires can go a long way toward helping reduce CO2 emissions.


Pharma / Medical

Halobutyl rubber of the X_Butyl® brand from ARLANXEO protects pharmaceutical products from external influences such as moisture, light and ozone, heat and cold.