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Isobutylene isoprene copolymer

A living cationic polymeriza tion of isobutylene and copolymeriza tion of isobutylene and isoprene has been demonstrated (22,23). Living copolymerizations, which proceed in the absence of chain transfer and termination reactions, yield the random copolymer with narrow mol wt distribution and well-defined stmcture, and possibly at a higher polymerization temperature than the current commercial process. The isobutylene—isoprene copolymers are prepared by using cumyl acetate BCl complex in CH Cl or CH2CI2 at —30 C. The copolymer contains 1 8 mol % trans 1,4-isoprene... [Pg.480]

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]

Compound A—A blend of cured and uncured isobutylene-isoprene copolymer... [Pg.31]

Table IV shows the data on rigidity changes of the end-sealing compounds at two dose levels. Rigidity was determined by torsional braid analysis (5). These data indicate that the blend of cured and uncured isobutylene-isoprene copolymer was softened most by the irradiation treatment, the blend of polychloroprene and butadiene-styrene copolymer softened the least, and the blend of polychloroprene and the uncured isobutylene-isoprene copolymer was intermediate. Increasing the irradiation dose from 3-4 Mrad to 6-7.5 Mrad decreased the rigidity of the three end-sealing compounds. The irradiation temperature did not significantly influence rigidity. Table IV shows the data on rigidity changes of the end-sealing compounds at two dose levels. Rigidity was determined by torsional braid analysis (5). These data indicate that the blend of cured and uncured isobutylene-isoprene copolymer was softened most by the irradiation treatment, the blend of polychloroprene and butadiene-styrene copolymer softened the least, and the blend of polychloroprene and the uncured isobutylene-isoprene copolymer was intermediate. Increasing the irradiation dose from 3-4 Mrad to 6-7.5 Mrad decreased the rigidity of the three end-sealing compounds. The irradiation temperature did not significantly influence rigidity.
The production test showed that the epoxy phenolic enamel was the preferred enamel for coating tinplate containers used in packaging irradiation-sterilized ham and beef. The preferred end-sealing compound for the same application was the blend of cured and uncured isobutylene-isoprene copolymer. [Pg.40]

The evaluation of the components of the tinplate container showed that the preferred enamel for irradiation processing was the epoxy phenolic the preferred end-sealing compound was the blend of cured and uncured isobutylene—isoprene copolymer. Component testing of tinplate and solder for possible changes in mechanical properties, microstructure, and corrosion resistance indicated that the radiation caused... [Pg.40]

Hydroxpropyl Cellulose Hydroxypropyl Methylcellulose Isobutylene-Isoprene Copolymer Locust Bean Gum... [Pg.130]

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]

Establishments primarily engaged in manufacturing synthetic rubber by polymerization or copolymerization. An elastomer for the purpose of this classification is a rubber-like material capable of vulcanization, such as copolymers of butadiene and styrene, or butadiene and acrylonitrile, polybutadienes, chloroprene rubbers, and isobutylene-isoprene copolymers. Butadiene copolymers containing less than 50 percent butadiene are classified in Industry 2821. Natural chlorinated rubbers and cyclized rubbers are considered as semifinished products and are classified in Industry 3069. [Pg.453]

To check the accuracy of our method at low 0-pinene values, we analyzed the PMR spectrum of an isobutylene-isoprene copolymer which according to commercial specifications contained 1.S mole% unsaturation (This material, Butyl 268, has been obtained by the courtesy of the ENJAY Chemical Company). Using our spectroscopic method, we found 1.S mole% unsaturation in this material. [Pg.7]

Synonyms cas 94-14-4 p-aminobenzoic acid isobutyl ester (2-methyl)-p-aminobenzoate Isobutylene-Isoprene Copolymer... [Pg.176]

The objects of our investigations were four kinds of elastomers, of different structure and polarity, viz. cis-1,4-polybutadiene (BR)> butadiene-acrylonitrile copolymer (NBR), isobutylene-isoprene copolymers (IIR) and ethylene-propylene-diene terpolymer (EPT). They were mixed with plastomers low density polyethylene (PE] ), polystyrene (PS), polytetrafluoroethylene (PTFE), polyvinyl chloride (PVC), polycaproamide (PCA) and polyacrylonitrile (PAN) (Table 1). The concentration of the plastomers in the mixtures was changed in the range from 0 to 50 pph of the elastomer. The polymers were blended at temperature T = 423 K by means of the micromill of the Plasti--Corder apparatus. After 24 hours, crosslinking substances, dicurayl peroxide (DCP) or sulphur and diphenylguanidine (S, DPG), were added at room temperature. The composition of the mixtures is given in Table 2. [Pg.144]

Synonyms 1,3-Butadiene-2-methyl polymer with 2-methyl-l-propene Butyl rubber HR Isobutylene/isoprene copolymers 3-Methyl-1,3-butadiene polymer with 2-methyl-1 -propene Poly (isobutylene-co-isoprene) Definition Copolymer of isobutylene and isoprene monomers Formuia (CsHs C4H8),... [Pg.1157]

Poly (isobutylene-co-isoprene). See Isobutylene/isoprene copolymer... [Pg.1299]

Foamkill 810F Isobutylene/isoprene copolymer Urea-formaldehyde resin... [Pg.1769]

See other pages where Isobutylene isoprene copolymer is mentioned: [Pg.223]    [Pg.296]    [Pg.422]    [Pg.29]    [Pg.89]    [Pg.776]    [Pg.484]    [Pg.738]    [Pg.223]    [Pg.110]    [Pg.233]    [Pg.233]    [Pg.233]    [Pg.741]    [Pg.741]    [Pg.124]    [Pg.465]    [Pg.204]    [Pg.707]    [Pg.138]    [Pg.974]    [Pg.738]    [Pg.143]    [Pg.811]    [Pg.110]    [Pg.1014]    [Pg.1157]   


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Brominated isobutylene-isoprene copolymer

Chlorinated isobutylene-isoprene copolymer

Copolymer of isobutylene and isoprene

ISOPRENE COPOLYMER

Isobutylene

Isobutylene-isoprene

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