Rubber, urethane

Peak Notation Assignment of Main Peaks Molecular Weight Retention Index Relative Intensity 

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Urethane rubbers have found steadily increasing use for oil seals, shoe soles and heels, fork-lift truck tyres, diaphragms, chute linings and a variety of mechanical applications. Fabric coatings resistant to dry cleaning are a recent development. In many of these applications high elasticity is not an important prerequisite so that the polyurethane rubbers must be compared not only with other rubbers but also with a variety of thermoplastics. 

Chemical Reactivity - Reactivity with Water Reacts violently to form flammable hydrocarbon gases Reactivity with Common Materials Not compatible with silicone rubber or urethane rubbers Stability During Transport Stable Neutralizing Agents for Acids and Caustics Not pertinent Polymerization Not pertinent Inhibitor of Polymerization Not pertinent. 

Aryloxyphosphazene copolymers can also confer fireproof properties to flammable materials when blended. Dieck [591] have used the copolymers III, and IV containing small amounts of reactive unsaturated groups to prepare blends with compatible organic polymers crosslinkable by the same mechanism which crosslinks the polyphosphazene, e.g. ethylene-propylene and butadiene-acrylonitrile copolymers, poly(vinyl chloride), unsaturated urethane rubber. These blends were used to prepare foams exhibiting excellent fire retardance and producing low smoke levels or no smoke when heated in an open flame. Oxygen index values of 27-56 were obtained. 

We take advantage of the shock absorbing characteristics of thermoplastic urethane rubbers in automotive, motorcycle, and bicycle suspensions and power transmission systems. Industrial shock absorbing applications include buffers for elevators and cranes. 

Zinc Borate (2Zn0-3B203-3.5H20) is a unique multifuntional fire retardant. It can function as a flame retardant, smoke suppressant, afterglow suppressant, as well as an anti-tracking agent in polymers. It has been used extnesively as a fire retardant in PVC, polyolefin, nylon, polyester, epoxy, acrylic, urethane, rubbers, etc. 

Mitsubishi Electric Corporation (1981) Fire resistant liquid urethane rubber. Japan Kokai 8,161,424 Chem. Abstr.,... 

ZDEC is used in the following applications as a fast primary or secondary vulcanization accelerator in NR, SBR, IIR, EPDM and for natural and synthetic latex a stabilizer in butyl, butadiene, and urethane rubbers an antioxidant in rubber-based adhesive systems a stabilizer in cement a heat stabilizer for polyethylene. 

Use Manufacture of ammonium nitrate for fertilizer and explosives, organic synthesis (dyes, drugs, explosives, cellulose nitrate, nitrate salts), metallurgy, photoengraving, etching steel, ore flotation, urethanes, rubber chemicals, reprocessing spent nuclear fuel. 

Fig. 9.2.8 Tz parameter imaging with a surface coil, (a) The phantom consists of three sheets from poly(urethane) rubber. A magnetic-field gradient was applied perpendicular to the surface coil for space encoding along the depth axis y. (b) A two-pulse sequence with flip angles a and 2a, respectively, was used for excitation, (c) Stack of ID images for different echo times fg = 2r. (d) 7) parameter image extracted from the signal decays in c.

Styrene-chloroprene rubbers Styrene-isoprene rubbers Thiol rubbers Urethane rubbers Vulcanized oils... 

Stycast . [Emerson Cuming Grace NV] Epoxy resins or urethane rubbers casting resins for impregnation, potting. 

TRIISOBUTYLALUMINUM (100-99-2) Extremely flammable liquid (flash point <39°F/<4°C). Pyrophoric ignites spontaneously on contact with air. Reacts with water. A strong reducing agent. Violent reaction with oxidizers. Reacts with acids, carbon dioxide, alcohols, amines, ammonia, halogens, halogenated hydrocarbons. Attacks silicone and urethane rubbers. Store under inert gas blanket. Reacts with most common fire extinguishers ... 

Polyurethane rubbers, in general, and the Vulkollan-type rubbers, in particular, possess certain outstanding properties. They usually have higher tensile strengths than other rubbers and possess excellent tear and abrasion resistance. The urethane rubbers show excellent resistance to ozone and oxygen (in contrast to diene rubbers) and to aliphatic hydrocarbons. However, they swell in aromatic hydrocarbons and undergo hydrolytic decomposition with acids, alkalis, and prolonged action of water and steam. 

Peroxides are vulcanizing agents for elastomers, which contain no sites for attack by other types of vulcanizing agents. They are useful for ethylene-propylene rubber (EPR), ethylene-vinyl acetate copolymers (EAM), certain millable urethane rubbers, and silicone mbbers. They generally are not useful for vulcanizing butyl rubber (poly[isobutylene-co-isoprene]) because of a tendency toward chain scission, rather than crosslinking, when the polymer is subjected to the action of peroxide. 

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