Bromobutyl Rubber Stopper Properties

Polyisobutylene also known as pib or polyisobutene c 4 h 8 n is the homopolymer of isobutylene or 2 methyl 1 propene on which butyl rubber is based.

Bromobutyl rubber stopper properties.

Bromobutyl rubbers properties and applications. In the us and european markets serum vial stoppers are commonly available in both bromobutyl and chlorobutyl rubber for use in pharmaceutical packaging. Bromobutyl rubber is an excellent choice for pharmaceutical stoppers and seals applications due to low levels of additives and impurities high impermeability to moisture and air chemical and biological inertness resistance to aging and heat sterilization and easiness to vulcanize using low levels of clean curatives. There is no significant distinction between bromobutyl and chlorobutyl as the properties of these elastomers are very similar.

Vulcanization heating and curing of natural rubber results in the cross linking of individual polymer chains that forms a copolymer of isobutylene and to a smaller extent isoprene. Subsequent halogenation results in a halobutyl rubber typically bromobutyl or chlorobutyl. Bromobutyl chlorobutyl bromo chloro isobutylene isoprene. Butyl rubber sometimes just called butyl is a synthetic rubber a copolymer of isobutylene with isoprene the abbreviation iir stands for isobutylene isoprene rubber.

Butyl rubber is produced by polymerization of about 98 of. Bromobutyl biir is a copolymer of isobutylene and small amounts of brominated isoprene which provides unsaturated sites for vulcanization this elastomer has many of the attributes of butyl rubber including low gas and moisture permeability good vibration damping low glass transition temperature excellent resistance to ageing and weathering. Halogen has only slight effect on the principal characteristics of butyl rubber. These elastomers are obtained by continuous halogenization of butyl rubber.