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a polymer of isobutylene, [—C(CH3)2—CH2—]n.

Polyisobutylenes are viscous liquids with molecular weight of 10,000–50,000 or rubbery, amorphous products with a molecular weight of 70,000–225,000 that have cold flow. Their softening point is 185°-200°C and they do not decompose up to 350°C, although their mechanical properties deteriorate significantly even at 100°C; they retain their elasticity down to – 50°C.

The characteristic features of polyisobutylenes are low gas permeability and high resistance to the action of acids, alkalies, and solutions of salts, as well as high dielectric indexes (loss tangent, 0.0002 at 50 hertz). They degrade gradually under the action of sunlight and ultraviolet rays (the addition of carbon black slows this process). Polyisobutylenes are soluble in hydrocarbons, chlorinated hydrocarbons, and ether.

In industry, polyisobutylenes are produced by ionic polymerization of the monomer at temperatures from –80° to – 100°C; they are processed using the ordinary equipment of the rubber industry. Polyisobutylenes combine easily with natural or synthetic rubbers, polyethylene, polyvinyl chloride, and phenol-formaldehyde resins.

Polyisobutylenes are used in the production of electrical insulation and anticorrosion coatings for chemical apparatus and pipelines and in the preparation of adhesives and the production of waterproof fabrics and hermetic compounds. Polyisobutylenes with molecular weights of 10,000–20,000 are used as additives and thickeners in lubricants.

Polyisobutylenes are produced in the USSR, the Federal Republic of Germany (Oppanol and Dynagen), and the USA (Vistanex).


Spravochnik rezinshchika. Moscow, 1971. Pages 184–91.
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References in periodicals archive ?
Polyisobutylene appears to slightly delay the burning of short hydrocarbon molecules, which then hasten the burning of the longer hydrocarbons, Waters says.
Table-6: Dimensions of the adsorbed polymer on carbon black in decalin and concentration of stabilizing units (polyhydroxystearic acid in Hypermer LP1 and Hypermer B246 and polyisobutylene in OLOA 11000) in the adsorbed layer.
The use of polyisobutylene is anticipated to increase the durability (resistance to degradation).
David Marshal, director of new business development, says the new Sibstar TPVs are silane-crosslinked polyisobutylene (PIB) in PP or HDPE matrices.
(29) The middle block of these triblock copolymers is flexible and rubbery; i.e., polyisobutylene or hydrogenated polyisobutylene with succinate end groups (Lubrizol 2724, 2722, and 5603 from Lubrizol Corporation and Glissopal SA from BASF), or polyisoprene or its hydrogenated derivative with polyethylene oxide end blocks.
* Spectra of solids in an open environment such as 2-(dimethylamino)ethane thiolhydrochloride, atrazine, and C4 (a mixture of RDX + polyisobutylene + di(2-ethylhexyl)sebacate + fuel oil) (see Figure 11), were easily obtained.
British Petroleum plc is about to resubmit details of its proposed merger with Amoco to the European Commission's Merger Task Force, which, after examining the original dossier sent in on September 24, has asked for more information about the companies' activities in the chemical sector, particularly polyisobutylene. Any overlap needs to be identified and the Commission needs to clarify if the relevant market shares of the proposed deal will create the world's largest isobutylene company with a 39% share of the market.
Their business relationship was recently underscored by their memorandum of understanding with South Korean contractor Daelim for Saudi Arabia's first polyisobutylene plant , which was also be located within Jubail.
The firm's in-depth product line of world-sourced manufacturing additives includes antioxidants, blowing agents and foam accelerators, coagents and curing agents, elastomer accelerators, elastomer/thermoplastic processing additives and lubricants, ester plasticizers, functional and standard mineral fillers, metal oxides, hydroxides and stearates, mold releases and external lubricants, paraffin/ microcrystalline, polyethylene, sugar cane, Fischer Tropsch waxes, polyethylene glycol (PEG, various grades), silane coupling agents and crosslinkers, specialty polymers (such as various weights of polyisobutylene), and tackifier resins.
Distinct parts of the deposit spectrum are in accordance with reference spectra of a high molecular PIBSI sample (PIBSI: polyisobutylene succinimides).
In a previous article, we tested proof-of-principle of this idea [24], We examined the effect of adding 5 wt% polytetrafluoroethylene (PTFE) particles to three different polymers: polyisobutylene (PIB), polydimethylsiloxane (PDMS), and polystyrene (PS) of very low molecular weight.
LTS develops and utilizes adhesive systems including skin contact acrylic PSAs, stabilized silicone PSAs and polyisobutylene adhesives (PIBs).