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Epoxide, poly functional

Carbox> I terminated polybuladicnc polymers require curing in order to form a tridimensional network. Poly functional epoxides and aziridines arc used for cross-linking. [Pg.666]

The asymmetric epoxidation of functionalized alkenes still attracts considerable attention. Synthetic chemists continue to be in search of new and improved routes to epoxides, since they provide versatile intermediates for natural product synthesis. The topic of preparative techniques for chiral epoxides is seldom broached without the mention of the Sharpless epoxidation. Indeed, the impact of this protocol cannot be overestimated, as new applications continue to be reported. For example, linear poly(tartrate ester) ligands have been used this past year to generate a solid-supported Sharpless-type catalyst <97CC123>. [Pg.49]

Song, J., Bodis, J., and Fhiskas, J.E. Direct functionalization of poly isobutylene by living initiation with alpha-methylstyrene epoxide, J. Polym. Set, Polym. Chem., 40, 1005, 2002. [Pg.219]

This process has, however, not yet found industrial application. Similarly, poly-isoprenoids can be epoxidized regioselectively in co-position to functional groups (Table 4, No. 16-19) Polymer-bound mediators can also be used in this... [Pg.26]

The principle of miniemulsion polymerization to polyadditions of epoxyresins was successfully transferred to mixtures of different epoxides with varying diamines, dithiols, or diols which were heated to 60°C to form the respective polymers [125]. The requirement for the formulation of miniemulsions is that both components of the polyaddition reaction show a relatively low water solubility, at least one of them even below 10 5 g l1. The diepoxide bisphenol-A-diglycidylether was successfully used as epoxy component. In order to vary the obtained polymeric structure, tri- and tetra-functionalized epoxides were also used. As amino components a NH2 terminated poly(propylene oxide) with Mw=2032 g mol1, 4,4 -diaminobibenzyl, 1,12-diaminododecane, and 4,4 -di-aminodicyclohexylmethane were applied. As other addition components beside amine, 1,6-hexanedithiol and Bisphenol A were used. The hydrophobic compo-... [Pg.114]

Oxidation is the first step for producing molecules with a very wide range of functional gronps because oxygenated compounds are precursors to many other prodncts. For example, alcohols may be converted to ethers, esters, alkenes, and, via nncleophilic substitution, to halogenated or amine products. Ketones and aldehydes may be used in condensation reactions to form new C-C double bonds, epoxides may be ring opened to form diols and polymers, and, finally, carboxylic acids are routinely converted to esters, amides, acid chlorides and acid anhydrides. Oxidation reactions are some of the largest scale industrial processes in synthetic chemistry, and the production of alcohols, ketones, aldehydes, epoxides and carboxylic acids is performed on a mammoth scale. For example, world prodnction of ethylene oxide is estimated at 58 million tonnes, 2 million tonnes of adipic acid are made, mainly as a precursor in the synthesis of nylons, and 8 million tonnes of terephthalic acid are produced each year, mainly for the prodnction of poly(ethylene terephthalate) [1]. [Pg.181]

In a reversed way, cationically prepared end-functional polymers are used to quench other living polymers. For example, living anionic polystyrene may be terminated by polyisobutenes with silylchloride terminals [119,120] or epoxide ends [121,122] and by poly(vinyl ethers) with acetal terminals [123], The former case is reported to give H-shaped, tetraarmed block copolymers. [Pg.398]

Chlorinated, sulfonated, chlorosulfonated or epoxidized polymers, homopolymers and copolymers of functionalized monomers, e.g. poly(methacryl aldehyde), poly(2,3-epoxypropyl acrylate), poly(4-vinylphenol), poly(propylene-co-10-unde-cene-l-ol), poly(butadiene-co-methacryl aldehyde), poly(butadiene-co-acrylic acid), poly(ethylene-co-alkyl acrylate), poly(alkyl acrylate-co-2,3-epoxypropyl acrylate), poly(alkyl acrylate-co-maleic anhydride), poly(styrene-co-4-vinylbenzyl chloride)... [Pg.131]

Many authors elucidated functionalization of polymers containing reactive oxirane moieties. Epoxidized NR, BR, IR and/or the respective model hydrocarbons, poly (butadiene-co-isoprene, various epoxy resins, poly (2,3-epoxypro-pyl methacrylate) and its copolymers or grafted systems were mostly exploited. Stabilizers based on epoxidized unsaturated rubbers are of the top interest. The mechanism of the functionalization process was studied in details by means of 3,4-epoxy-4-methylheptane and 1,2-epoxy-3-ethyl-2-methylpentane as model compounds [289]. The ring opening of the asymmetric oxirane is regiospecific. Aliphatic primary amines attack the least substituted carbon atom and can be involved in crosslink formation. Aromatic primary and secondary amines are less reactive than aliphatic ones because of their lower basicity the attack on the least substituted carbon atom is however preferred too. [Pg.136]

Poly(glycidyl methacrylate) (PGMA), a well-known negative electron beam resist first reported by Hirai et al. (55), actually functions as a positive-tone resist upon DUV exposure (Table 3.1) (56). The epoxide functionality responsible for cross-linking under electron beam exposure does not absorb in the DUV region, and the response of PGMA to DUV radiation is determined by the absorption due to the n — tt transition of the carbonyl chromo-... [Pg.134]

The most important inference is that Chemisorption is a direct response to carboxyl group concentration indicated by the XPS photopeak component at 288.7 eV. It seems likely that weak add functionality is of minor import to applications for surface treatments, while interfacial phenomena such as practical adhesion may be sensitive to small concentrations of very high site energies. Interphase modification in epoxy resins, for example, can occur by direct reaction of epoxide groups with surface carboxyls (17), or by accelerated cure chemistry near the surface (39). Carboxyl groups on carbon surfaces may interact with basic moieties in polymers such as polycarbonate or poly(ethylene)oxide (40=42), or promote interfacial crystallinity that improves impact strength and other aspects of composite performance (43, M)-... [Pg.215]

L-24 as a ligand, up to 85—90% yield. The linking reaction of a poly(tBA) with a bromide terminal was also possible with divinylbenzene, whereas the other two divinyl compounds led to side reactions.328 The yield of star polymers can be increased up to 95% with the use of additives. The a-end-functionalized linear polymers afford surface-functionalized star polymers with various functional groups such as alcohols, amines, epoxides, and nitriles. [Pg.502]

Golub (16) found, using Ir and NMR, that functional groups of epoxide and alcohol are mainly formed In the oxidation of poly-butadlene in the temperature range of 90-180°C. These two products suggest the addition of the peroxy radical to the double bond to form an alkoxy radical and an epoxide group ... [Pg.77]


See other pages where Epoxide, poly functional is mentioned: [Pg.154]    [Pg.154]    [Pg.903]    [Pg.368]    [Pg.923]    [Pg.154]    [Pg.30]    [Pg.218]    [Pg.35]    [Pg.94]    [Pg.415]    [Pg.481]    [Pg.136]    [Pg.1021]    [Pg.43]    [Pg.665]    [Pg.115]    [Pg.119]    [Pg.65]    [Pg.375]    [Pg.381]    [Pg.322]    [Pg.506]    [Pg.511]    [Pg.375]    [Pg.381]    [Pg.423]    [Pg.184]    [Pg.415]    [Pg.136]    [Pg.439]    [Pg.195]    [Pg.246]    [Pg.343]    [Pg.137]    [Pg.395]    [Pg.399]   
See also in sourсe #XX -- [ Pg.279 ]




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Functionalization poly

Functionalized poly

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Poly functionalities

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