Polystyrene, metalation

Aluminum Human hand Brass 0 All metals Polystyrene (USA)... 

Metallated polystyrenes are versatile intermediates for the preparation of a number of polystyrene derivatives. Metallated polystyrene has been prepared from haloge-nated polystyrenes by halogen-metal exchange [41,42,65,66] and by direct metallation of polystyrene [67-69] (see Chapter 4). Electrophiles suitable for the derivatization of metallated polystyrene include carbon dioxide, carbonyl compounds, sulfur, trimethyl borate, isocyanates, chlorosilanes, alkyl bromides, chlorodiphenylphosphine, DMF, oxirane, selenium [70], dimethyldiselenide [71], organotin halides [69], oxygen [72], etc. [41,42,65-67],... 

Several workers have used this approach to metalate hydrocarbon polymers. Plate and co-workers (98), for example, metalated polystyrene and monitored the butane evolution by gas chromatography. They reported a 40% catalyst efficiency. However, they did not report the grafting efficiency or the overall effectiveness of this metalating reagent. 

Oxides, mixed oxides, aluminosilicates, silica, metals, polystyrene, copolymers of styrene with divinylbenzene and 4-vinylpyr-idine, copolymers of acrylic monomers, coal, graphite... 

Though several groups have observed attachment of alkali metal cation to polystyrene, " most MALDI practitioners add silver or copper salts to produce good metal-polystyrene cation signals, dithranol as a Good... 

When polystyrenelithium is aminated by a reagent prepared from methoxyamine and methyl-lithium, two reaction mechanisms are possible. One may proceed via nitrene intermediates and the other via electophilic nitrenium ions. Many other reactions of polystyrenelithium can be found in the literature. Sodium metalated polystyrene reacts in a similar manner ... 

Polystyrene with phosphonic or phosphinic attached groups shows selective ion exchange towards metals. Polystyrene-supported phosphinates (12.202c) form better selective ion extraction resins than the corresponding sulphonic or carboxylate derivatives [34]. Phosphonate and phosphinate resins can be used for selective extraction of Pb (12.169). 

Structural Components. In most appHcations stmctural foam parts are used as direct replacements for wood, metals, or soHd plastics and find wide acceptance in appHances, automobUes, furniture, materials-handling equipment, and in constmction. Use in the huil ding and constmction industry account for more than one-half of the total volume of stmctural foam appHcations. High impact polystyrene is the most widely used stmctural foam, foUowed by polypropylene, high density polyethylene, and poly(vinyl chloride). The constmction industry offers the greatest growth potential for ceUular plastics. 

AppHcation of an adhesion-promoting paint before metal spraying improves the coating. Color-coded paints, which indicate compatibiHty with specific plastics, can be appHed at 20 times the rate of grit blasting, typically at 0.025-mm dry film thickness. The main test and control method is cross-hatch adhesion. Among the most common plastics coated with such paints are polycarbonate, poly(phenylene ether), polystyrene, ABS, poly(vinyl chloride), polyethylene, polyester, and polyetherimide. 

Polymer—Cp—MCl complexes have been formed with the Cp-group covalendy bound to a polystyrene bead. The metal complex is uniformly distributed throughout the bead, as shown by electron microprobe x-ray fluorescence. Olefin hydrogenation catalysts were then prepared by reduction with butyl hthium (262). 

In another appHcation expanded polystyrene foam panels, 1.2 x 2.4 m, are faced with a wire mesh and mounted ia a metal channel bolted to a coacrete slab. These panels are then sprayed on both sides with plaster, which is anchored to the wire mesh and forms the iaterior and exterior surfaces. Roof and iaterior partitioas provide low cost housiag for mild climates. 

Lake Red C is an example of a pigment that has been made insoluble by a heavy metal. In this case the metal is barium one barium ion precipitates two molecules. Other metals used are calcium, strontium, manganese, and aluminum. This pigment is used in polystyrene. 

Heavy metals Cation Polystyrene matrix Chelating functional groups Mineral acids... 

The capacity of studied organopolymeric sorbents depends on metal nature (Pd (II) > Au (III) > Pt (IV)) as well as on the composition and stmcture of sorbent matrix (polyvinylpyridine macroporous > polystyrene macroporous > polystyrene fibrous). 

Ion exchange resins are also useful for demineralising biochemical preparations such as proteins. Removal of metal ions from protein solutions using polystyrene-based resins, however, may lead to protein denaturation. This difficulty may be avoided by using a weakly acidic cation exchanger such as Bio-Rex 70. 

The synthesis of new polymeric materials having complex properties has recently become of great practical importance to polymer chemistry and technology. The synthesis of new materials can be prepared by either their monomers or modification of used polymers in industry. Today, polystyrene (PS), which is widely used in industrial applications as polyolefins and polyvinylchlorides, is also used for the production of plastic materials, which are used instead of metals in technology. For this reason, it is important to synthesize different PS plastic materials. Among the modification of PS, two methods can be considered, viz. physical and chemical modifications. These methods are extensively used to increase physico-mechanical properties, such as resistance to strike, air, or temperature for the synthesizing of new PS plastic materials. 

Recently, Deligoz and Yilmaz [51] prepared three polymeric calix[4]arenes, which were synthesized by reacting chloromethylated polystyrene with 25,26,27-tribenzoyloxy-28-hydroxy calix[4]arene (2a, 3a) and po-lyacryloyl chloride with 25,26,27,28-tetraacetoxy ca-lix[4]arene (4a). After alkaline hydrolysis of the polymers, they were utilized for selective extraction of transition metal cations from aqueous phase to organic phase. 

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