Isobutene-isoprene

BUR bromo-isobutene-isoprene rubber (brominated butyl rubber)... 

Isobutene Isoprene Divinylbenzene 4-Methylstyrene Basic monomer Comonomer for crosslinking Comonomer for branching and halogenation Comonomer for halogenation... 

ISO 7663, 1995. Rubber, Halogenated Isobutene-Isoprene (BUR and CIIR) - Evaluation procedure. 

The butyl rubber (HR, as abbreviated in the ISO nomenclature for isobutene-isoprene rubber) random copolymer of isobutene with 0.5-2.5 wt% isoprene, and its haloderivatives (XIIR). 

As previously noticed, butyl rubber (HR), poly(methylpropene-co-2-methyl-1,3-butadiene), is a random copolymer of isobutene and 0.7-2.2 mol% of isoprene. The industrial slurry process used all over the world consists in a low-temperature copolymerization initiated by A1C13 in meth-ylchloride. In contrast to 1,3-butadiene, isoprene copolymerizes readily with the more reactive isobutene. Reactivity ratios of the pair isobutene-isoprene, ri = 2.5 0.5 and r2 = 0.4 0.1, measured at the conditions of industrial process [10], show that the copolymerization behaves ideally (ri-r2 = 1), and, at the used low concentration of isoprene, isolated units of this latter comonomer are randomly distributed along the chain with 90% M-p-aiw-enchainment [52,53] ... 

Figure 8 General formula for cross-linked terpolymer of isobutene, isoprene, and divinylbenzene.

Attempts were made to overcome the difficulties above mention by ter-polymerizing isobutene, isoprene and divin bonzene, to partially cross-linked products, which can give further radical curing ... 

The unusual combination of a Lewis acid and an electron acceptor has also been shown to be an efficient polymerization catalyst. Thus dialkyl-aluminium halides with chloranil, 1,3,5-trinitrobenzene, and 2,4,5,7-tetranitro-fluoren-9-one succeed in polymerizing isobutene and isobutene/isoprene mixtures to very high molecular weight polymers. Chloranil was examined in most... 

PP and PC are immiscible, thus excepting the exploratory use as a plastic paper, only the two ends of the concentration range have been explored, viz. addition of 5 wt% PP to PC (to improve processability of PC) [Dobkowski, 1980], or addition of <10 wt% of PC (to improve PP processability, enhance crystallinity and crystallization temperature, the appearance, modulus, and impact strength) [Liang and Williams, 1991]. For concentrations >10 wt% compatibilization is necessary. This is accomplished using ethylene-acrylic copolymer, cellulosics, PA, PVAc, or TPU [Goldblum, 1963, 1964] an acrylic elastomer, acrylic elastomer with PP-MA and either butyl mbber, or isobutene-isoprene mbber [Teijin Chem., 1982, 1983] SBR and EEA [Liu, 1984] MBS [Overton and Liu, 1984] or EVAc [Giles and Hirt, 1986],... 

Copolymerization initiated by A proceeds readily at low temperatures and gives isobutene—isoprene copolymers structurally identical to those prepared commercially utilizing a conventional Lewis-acid initiator. That is to say, there is no incorporation of isoprene in a 1,2- or 3,4-fashion, as would be anticipated at least in part for a Ziegler—Natta process. As with polyisobutene, lower temperatures result in higher molecular weights (polydispersities 2) while materials with high M values and a low polydisper-sity index could be obtained only at very low contents of isoprene. consistent with observations that chain-transfer processes are extremely facile following isoprene incorporation. - ... 

Polymerization of vinyl chloride Polyacrylates and polymetiiacrylates Butadiene, isopreal and tiien copolymers Cationic copolymerization of isobutene-isoprene with slurry AICI3 as tiie initiator and metiiyl chloride as diluent AICI3 slurry polymerization of propylene in tiie presence of transition metiiyl catalyst and excess monomer as a diluent Fluidized bed reactor is used in tiie gas phase poljmierization a powdered polymer is produced in a gaseous monomer-low pressure poljmierization of ethylene (HDPE) and propylene... 

Isoprene is used as the comonomer in butyl rubber (0.5-2.5 mol%) (Kresge et al., 1987) because the isobutene-isoprene reactivity ratios are more favorable for inclusion of the diene than those of the isobutene-butadiene pair (Kennedy, 1968). Thus, for the former pair, the r (isobutene) = 2.5, and r (isoprene) = 0.4 (Kennedy, 1968). It should be noted, however, that as discussed previously, such r values can be markedly influenced by the nature of the initiator and solvent used in the polymerization. The values just quoted are applicable to the commercial butyl rubber process, as described earlier. It has been shown that the isoprene unit enters the chain predominantly in a 1,4-conflguration (Chen and Field, 1967). 

ISO 9022-11 1994 Optics and optical instruments — Environmental test methods — Part 11 Mould growth ISO 9026 1991 Raw rubber or unvulcanized compounds — Determination of green sbength ISO 9924-1 2000 Rubber and rubber products — Determination of the composition of vulcanizates and uncured compounds by thermogravimetry — Part 1 Butadiene, ethylene-propylene eopolymer and terpolymer, isobutene-isoprene, isoprene and styrene-butadiene rubbers... 

Polymers Thermoplastic elastomers Styrene-butadiene-styrene (SBS), styrene-butadiene-rubber (SBR), styrene-isoprene-styrene (SIS), styrene-ethyl-butadiene-styrene (SEBS), ethyl-propyl-dien tetropolymer (EPDM), isobutene-isoprene copolymer (NR), polybutadiene (PBD),natural rubber (l),(2),(3),(4), [8]. [9], [10], [II], [13]... 

Isobutene-isoprene rubber butyl rubber (see also GR-I, PIBI) Interpenetrating polymer network Synthetic cis-1. 4-oolyisoprene... 

PIBI Isobutene-isoprene copolymer butyl rubber GR-I... 

This is accomplished using ethylene-acrylic copolymer, cellulosics, PA, PVAc, or TPU (Goldblum 1963, 1964) an acrylic elastomer, acrylic elastomer with PP-MA, and either butyl rubber or isobutene-isoprene rubber (Teijin Chem. 1982,1983) SBR and EEA (Liu 1984) MBS (Overton and Liu 1984) or EVAc (GUes and Hirt 1986). 

HDT Heat deflection temperature, heat distortion temperature HEMA Hydroxyethyl methacrylate HIPS High impact polystyrene HR Isobutene-isoprene rubber (butyl rubber)... 

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