BIMS rubber

Maiti et al. [14] have studied the effects of different nanoclays (namely, NA, 10A, 20A, and 30B) on the properties of BIMS rubber. They have characterized the clays and the rubber nanocomposites by means of FTIR, , and XRD. 

Table 7 Relaxation time (t), self-diffusion coefficient (D), and monomer friction coefficient (Co) of unfilled (B) and nanoclay-filled (BCLNA8) BIMS rubber...

In the literature, there are several reports that examine the role of conventional fillers like carbon black on the autohesive tack (uncured adhesion between a similar pair of elastomers) [225]. It has been shown that the incorporation of carbon black at very high concentration (>30 phr) can increase the autohesive tack of natural and butyl rubber [225]. Very recently, for the first time, Kumar et al. [164] reported the effect of NA nanoclay (at relatively very low concentration) on the autohesive tack of BIMS rubber by a 180° peel test. XRD and AFM show intercalated morphology of nanoclay in the BIMS rubber matrix. However, the autohesive tack strength dramatically increases with nanoclay concentration up to 8 phr, beyond which it apparently reaches a plateau at 16 phr of nanoclay concentration (see Fig. 36). For example, the tack strength of 16 phr of nanoclay-loaded sample is nearly 158% higher than the tack strength of neat BIMS rubber. The force versus, distance curves from the peel tests for selected samples are shown in Fig. 37. 

Kumar KD, Tsou AH, Bhowmick AK (2010) Unique tackification behavior of needle-like sepiolite nanoclay in brominated isobutylene-co-p-methylstyrene (BIMS) rubber. Macromolecules 43 4184—4193... 

Isobutylene is used to produce BIMS rubber, which is mixed with nylon-6 in a dynamic vulcanization process to create a new thermoplastic vulcanizate (TPV). 

The X-ray diffraction peaks observed in the range of 3°-10° for the modified clays disappear in the rubber nanocomposites. photographs show predominantly exfoliation of the clays in the range of 12 4 nm in the BIMS. Consequently, excellent improvement in mechanical properties like tensile strength, elongation at break, and modulus is observed by the incorporation of the nanoclays in the BIMS. Maiti and Bhowmick have also studied the effect of solution concentration (5, 10, 15, 20, and 25 wt%) on the properties of fluorocarbon clay nanocomposites [64]. They noticed that optimum properties are achieved at 20 wt% solution. At the optimized solution concentration, they also prepared rubber/clay nanocomposites by a solution mixing process using fluoroelastomer and different nanoclays (namely NA, 10A, 20A, and 30B) and the effect of these nanoclays on the mechanical properties of the nanocomposites has been reported, as shown in Table 4 [93]. 

Raman microimaging is used to estimate the effect of the siUca filler on phase separation in binary polymer blends composed of brominated poly(isobutylene-co-para-methyl) styrene (BIMS) and butyl rubber (HR). The domain sizes, relative concentration of polymer components within domains, and distribution of particulate silica filler and zinc stearate curative are characterised for blends of different compositions and history of ageing treatments. The presence of increased concentrations of precipitated silica results in better... 

BIMS-NR blends as sidewall components. In many of the applications, the saturated elastomer is considered a polymeric antioxidant for the diene rubber. It is believed that the higher molecular weight polyolefins are better in these applications due to limited interdiffusion and a more stable morphology. Some of the benefits in tensile properties and abrasion resistance of the blends may be due to the interdiffusion of high molecular chains of dissimilar elastomers across the phase interface. Significant advances have been made in modifying the structure of polyolefin elastomers to increase the compatibility to unsaturated elastomers. Tse et al. [50b] have shown that uncompatibilized blends of saturated elastomers and unsaturated elastomers are possible if the former contains substantial amounts (>12%) styrene residues. This is expected to be an important area of development in the future with the advent of new synthesis procedures for polyolefins. 

BIMS brominated isobutylene paramethyl styrene rubber... 

Blends of saturated with unsaturated rubbers, e.g., EPDM-NR and BIMS-NR, find application in the tire sidewall, where the saturated component could aid in environmental resistance. Compatibilization is likely required to form a stable blend morphology from such dissimilar components. 

Chlorobutyl provides flex resistance in the blend chlorobutyl rub-ber/EPDM rubber/NR for white sidewall tires and white sidewall cov-erstrips.22 An important application of chlorobutyl rubber in automotive hose is extruded air conditioning hose to provide barrier properties to reduce moisture gain and minimize refrigerant loss. The polymer is used in compounds for fuel line and brake line hoses. Brominated isobutylene-p-methylstyrene (BIMS) was shown to have... 

Isobutylenepara-methyl Styrene Rubber BIMSM BIMS... 

Brominated copolymer of isobutylene and para-methylstyrene (DIMS) is the latest new class of synthetic rubber that has been developed for the rubber industry. The sole producer of this new class of elastomer is ExxonMobil, which commercialized it successfully under the trade name Exxpro in the first decade of this new century. The advantage of this new polymer class vs. bromobutyl rubber is that this new elastomer possesses a completely saturated backbone and possesses more reactive benzylic bromine functionality than the bromine sites on the conventional bromobutyl backbone. This means that DIMS reportedly gives superior performance in service vs. BUR. This superiority is shown as better high-temperature resistance, better aging stability than either BUR or EPDM, better weathering resistance, and better ozone resistance. Also, BIMS provides the potential of imparting superior air permeability resistance. 

Basic feedstock for over 12 different elastomers Basic feedstock for many different rubber accelerators Very important feedstock for furnace carbon blacks Used for CR, CM, CSM, CIIR, CO, ECO, ADC, etc. Directly used for over ten different rubbers Used for production of over 14 different rubbers Used for adhesion promoters, tackifiers, curatives, PUR Needed for HR, CIIR, BUR, BIMS, AO, tackifiers, etc. Important feedstock for IR and HR rubber Feedstock for TBBS, CBS, MBS, MBTS accelerators Needed for carbon disulfide for rubber accelerators Needed for formaldehyde for adhesion, tackifiers, etc. Used for MDI and aniline for several rubber chemicals Feedstock for numerous rubber chemicals... 

Isobutylene-based elastomers include butyl rubber, the copolymer of isobutylene and isoprene, halogenated butyl rubber, star-branched versions of these polymers and the terpolymer isobutylene-para-methylene styrene-bromo-para-methyl styrene (BIMS). Anumber of reviews on isobutylene-based elastomers are available (395, a.20, a.21). 

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