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Isobutylene-isoprene butyl

Several polymers based on 1,3-dienes are used as elastomers. These include styrene-1,3-butadiene (SBR), styrene-1,3-butadiene terpolymer with an unsaturated carboxylic acid (carboxylated SBR), acrylonitrile-1,3-butadiene (NBR or nitrile rubber) (Secs. 6-8a, 6-8e), isobutylene-isoprene (butyl rubber) (Sec. 5-2i-l), and block copolymers of isoprene or... [Pg.699]

Isobutylene + isoprene Butyl rubber Mediyl chloride AlClj Atm -140 slurrying in hot water... [Pg.262]

Natural rubber or polyisoprene (NR or IR) Ethylene propylene diene rubber (EPDM) Isobutylene-isoprene (butyl) rubber (HR)... [Pg.64]

RRA cure test recipe for HR reclaim, cured 30 min at 160°C. HR is isobutylene—isoprene mbber (butyl mbber). [Pg.19]

Butyl Rubber isobutylene—isoprene good good ... [Pg.189]

A partially cross-linked, isobutylene—isoprene—divinylbenzene terpolymer containing some unreacted substituted vinylbenzene appendages is commercially available from Polysar Division, Bayer AG. Because of the residual reactive functionality, it can be cross-linked by peroxides that degrade conventional butyl mbbets. It is employed primarily in the manufacture of sealant tapes and caulking compounds (31). [Pg.481]

Polyisobutylene and isobutylene—isoprene copolymers are considered to have no chronic hazard associated with exposure under normal industrial use. Some grades can be used in chewing-gum base, and are regulated by the PDA in 21 CPR 172.615. Vulcanized products prepared from butyl mbber or halogenated butyl mbber contain small amounts of toxic materials as a result of the particular vulcanization chemistry. Although many vulcanizates are inert, eg, zinc oxide cured chlorobutyl is used extensively in pharmaceutical stoppers, specific recommendations should be sought from suppHers. [Pg.487]

Until the mid-1950s the only polyolefins (polyalkenes) of commercial importance were polyethylene, polyisobutylene and isobutylene-isoprene copolymers (butyl rubber). Attempts to produce polymers from other olefins had, at best, resulted only in the preparation of low molecular weight material of no apparent commercial value. [Pg.247]

Abbreviation for isobutylene-isoprene rubbers, popularly known as butyl rubbers. [Pg.34]

Isobutylene-isoprene elastomer (butyl rubber Sparks and Thomas)... [Pg.743]

Other commercial copolymers which are typically random are those of vinyl chloride and vinyl acetate (Vinylite), isobutylene and isoprene (butyl rubber), styrene and butadiene (SBR), and acrylonitrile and butadiene (NBR). The accepted nomenclature is illustrated by EP, which is designated poly-ethylene-co-propylene the co designating that the polymer is a copolymer. When the copolymers are arranged in a regular sequence in the chains, i.e., ABAB, the copolymer is called an alternating copolymer. A copolymer consisting of styrene and maleic anhydride (SMA) is a typical alternating copolymer. [Pg.10]

To this category belong homopolymers of polyisobutylene, copolymers of isobutylene and isoprene (butyl rubber), chlorobutyl, and bromobutyl. All these have been produced commercially for decades. [Pg.111]

Butyl rubber is produced at very low temperature (below — 90°C) to control the rapid exotherm, and to provide high molecular weight. The process consists of charging isobutylene along with isoprene (2-4%) with an inert diluent such as methyl chloride to a reactor to which a Friedel-Crafts catalyst is added. The polymerization is very rapid, and the polymer forms in a crumb or slurry in the diluent. Heat is removed via the reactor jacket. The slurry is steam-stripped to remove all volatiles. The catalyst is neutralized, and antioxidants are added to the slurry prior to drying.53 The halogenated derivatives are produced by the direct addition of the halogen to a solution of the isobutylene-isoprene polymer. [Pg.707]

Thomas and Sparka synthesize isobutylene-isoprene rubber Butyl rubber is synthesized in the US... [Pg.435]

Polyisobutylene and polybutenes Isobutylene-isoprene copolymer (Butyl rubber) Polyacetal Poly(vinyl ether)s... [Pg.574]

Property Butyl/halobutyl (isobutylene- isoprene copolymer) N atur al/Isoprene (cis-1,4-polyisoprene) Nitrile (butadiene- Sdicone Neoprene acrylonitrile (polydi-(polycbloroprene) copolymer) metbysiloxane) Fluoro- elastomers (fluoro- rubber) Uretbane (polyesterisocyanate) EPDM (etbylene Butadiene propylenediene (cis-polybuta-monomer) diene) ... [Pg.1478]

Isobutylene isoprene H2C=C(CH3)2 H.2C=C(CH3)CH=CH2 Butyl rubber Inner tubes... [Pg.1269]

Elastomers include natural rubber (polyisoprene), synthetic polyisoprene, styrene-butadiene rubbers, butyl rubber (isobutylene-isoprene), polybutadiene, ethylene-propylene-diene (EPDM), neoprene (polychloroprene), acrylonitrile-butadiene rubbers, polysulfide rubbers, polyurethane rubbers, crosslinked polyethylene rubber and polynorbomene rubbers. Typically in elastomer mixing the elastomer is mixed with other additives such as carbon black, fillers, oils/plasticizers and accelerators/antioxidants. [Pg.408]

Isobutylene-isoprene rubbers, the copolymers containing 98% isobutylene and 2% isoprene cannot be made into hard rubbers because of the lack of adequate unsaturation. However a very hard butyl rubber vulcanisate can be obtained by admixture with SBR and high levels of sulfur. The water absorption of NR ebonite is 0.45% to 0.5% at a relative humidity of 97.2%. [Pg.76]

See other pages where Isobutylene-isoprene butyl is mentioned: [Pg.223]    [Pg.249]    [Pg.296]    [Pg.480]    [Pg.776]    [Pg.873]    [Pg.15]    [Pg.127]    [Pg.738]    [Pg.2]    [Pg.223]    [Pg.249]    [Pg.275]    [Pg.40]    [Pg.44]    [Pg.106]    [Pg.110]    [Pg.67]    [Pg.1469]    [Pg.122]    [Pg.1211]    [Pg.707]    [Pg.48]   


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