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Ionic rubber

Polymers can be modified by the introduction of ionic groups [I]. The ionic polymers, also called ionomers, offer great potential in a variety of applications. Ionic rubbers are mostly prepared by metal ion neutralization of acid functionalized rubbers, such as carboxylated styrene-butadiene rubber, carboxylated polybutadiene rubber, and carboxylated nitrile rubber 12-5]. Ionic rubbers under ambient conditions show moderate to high tensile and tear strength and high elongation. The ionic crosslinks are thermolabile and, thus, the materials can be processed just as thermoplastics are processed [6]. [Pg.441]

An ionic rubber comprising a low-temperature molten salt mixture and a small amount of high-molecular-... [Pg.499]

An ionic rubber comprising a low-temperature molten salt mixture and a small amount of high-molecular-weight polymer. On a structural level, these electrolytes have some features in common with gel electrolytes. They were first reported in the literature in 1993 [5] and are in the early stages of development. [Pg.628]

O.2UCIO4 is added with a small amount of polymer such as PPO and lithimn poly(lithium vinyl sulfonate), an ionic rubber that can transfer ions is obtained, with an ionic conductivity of 1(T S/cm at room temperature. However, the electrochemical window of the prepared ionic liquid currently is limited to about 3.5 V. As a result, the applications for the obtained gel polymer electrolyte are also limited and cannot meet the demands of high-voltage Uthiiun-ion batteries. [Pg.440]

Ionic Thermoplastic Elastomer Based on Maleated EPDM Rubber... [Pg.441]

Zinc salt of maleated EPDM rubber in the presence of stearic acid and zinc stearate behaves as a thermoplastic elastomer, which can be reinforced by the incorporation of precipitated silica filler. It is believed that besides the dispersive type of forces operative in the interaction between the backbone chains and the filler particles, the ionic domains in the polymer interact strongly with the polar sites on the filler surface through formation of hydrogen bonded structures. [Pg.450]

Total Ionic Strength Adjustment Buffer (TISAB). Dissolve 57 mL acetic acid, 58 g sodium chloride and 4g cyclohexane diaminotetra-acetic acid (CDTA) in 500 mL of de-ionised water contained in a large beaker. Stand the beaker inside a water bath fitted with a constant-level device, and place a rubber tube connected to the cold water tap inside the bath. Allow water to flow slowly into the bath and discharge through the constant level this will ensure that in the... [Pg.571]

An electric conductive rubber base containing carbon black is laminated with an electric conductive cover layer of phosphoric acid ester plasticizer and other ionic surfactants to prepare antistatic mats, where the covers have colors other than black. It is also reported that alkyl acid phosphates act as color stabilizer for rubber. Small amounts of phosphate esters are helpful in restoring reclaimed rubber to a workable viscosity [284,290]. Esters of phosphoric acid are used in the production of UV-stable and flame-retarded alkylbenzenesulfonate copolymer compositions containing aliphatic resins and showing a high-impact strength... [Pg.614]

A new class of solvents called ionic liquids has been developed to meet this need. A typical ionic liquid has a relatively small anion, such as BF4, and a relatively large, organic cation, such as l-butyl-3-methylimidazolium (16). Because the cation has a large nonpolar region and is often asymmetrical, the compound does not crystallize easily and so is liquid at room temperature. However, the attractions between the ions reduces the vapor pressure to about the same as that of an ionic solid, thereby reducing air pollution. Because different cations and anions can be used, solvents can be designed for specific uses. For example, one formulation can dissolve the rubber in old tires so that it can be recycled. Other solvents can be used to extract radioactive waste from groundwater. [Pg.327]

Ionic polymers are a special class of polymeric materials having a hydrocarbon backbone containing pendant acid groups. These are then neutralized partially or fully to form salts. lonomeric TPEs are a class of ionic polymers in which properties of vulcanized rubber are combined with the ease of processing of thermoplastics. These polymers contain up to 10 mol% of ionic group. These ionomeric TPEs are typically prepared by copolymerization of a functionalized monomer with an olefinic unsamrated monomer or direct functionalization of a preformed polymer [68-71]. The methods of preparation of various ionomeric TPEs are discussed below. [Pg.115]

Substantial work has been done on self-cross-linking rubber blends where two elastomers with opposite ionic charges interact with each other and form cross-links and in the process provide high level of compatibility. [Pg.301]

C04-0121. Lithopone, a brilliant white pigment used in paints, paper, and white rubber products, is a mixture of two insoluble Ionic solids, ZnS and BaSOq. Suggest how 1.0 kg of lithopone could be prepared by a precipitation reaction. [Pg.272]

When many molecules combine the macromolecule is termed a polymer. Polymerization can be initiated by ionic or free-radical mechanisms to produce molecules of very high molecular weight. Examples are the formation of PVC (polyvinyl chloride) from vinyl chloride (the monomer), polyethylene from ethylene, or SBR synthetic rubber from styrene and butadiene. [Pg.25]

Ionic Polymerization. Ionic polymerizations, especially cationic polymerizations, are not as well understood as radical polymerizations because of experimental difficulties involved in their study. The nature of the reaction media is not always clear since heterogeneous initiators are often involved. Further, it is much more difficult to obtain reproducible data because ionic polymerizations proceed at very fast rates and are highly sensitive to small concentrations of impurities and adventitious materials. Butyl rubber, a polymer of isobutene and isoprene, is produced commercially by cationic polymerization. Anionic polymerization is used for various polymerizations of 1,3-butadiene and isoprene. [Pg.15]


See other pages where Ionic rubber is mentioned: [Pg.441]    [Pg.449]    [Pg.512]    [Pg.611]    [Pg.168]    [Pg.112]    [Pg.512]    [Pg.643]    [Pg.212]    [Pg.441]    [Pg.449]    [Pg.512]    [Pg.611]    [Pg.168]    [Pg.112]    [Pg.512]    [Pg.643]    [Pg.212]    [Pg.72]    [Pg.321]    [Pg.136]    [Pg.278]    [Pg.880]    [Pg.150]    [Pg.442]    [Pg.444]    [Pg.447]    [Pg.449]    [Pg.823]    [Pg.225]    [Pg.54]    [Pg.470]    [Pg.377]    [Pg.377]    [Pg.872]    [Pg.96]    [Pg.1112]    [Pg.336]    [Pg.410]   
See also in sourсe #XX -- [ Pg.628 ]




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