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Poly derivatives, preparation

T. Yamamoto, T. Murauyama, Z.-H. Zhou, T. Ito, T. Fukuda, Y. Yoneda, F. Begum, T. Ikeda, S. Sasaki, H. Takezoe, A. Fukuda, and K. Kubota, -ir-Conjugated poly(pyridine-2,5-diyl), poly(2,2 -bipyridine-5,5 -diyl), and their alkyl derivatives. Preparation, linear structure, function as a ligand to form their transition metal complexes, catalytic reactions, //-type electrically conducting properties, optical properties, and alignment on substrates, J. Am. Chem. Soc., 116 4832-4845,... [Pg.291]

Poly-a-L-glutamic acid derivatives prepared by Piccariello et al. (4) were functionalized with iV-octanoyl-L-triiododiyronine and used in the treatment of thyroid disorders. [Pg.479]

TABLE 2. Physical Properties of Poly(thiocarbonate-co-thiourethane) Step 2 Derivatives Prepared by Condensing 2,4-Tolylene Diisocyanate with Step 1 Polythiocarbonates Described in Table 1 Prepared According to the Current Invention... [Pg.528]

In contrast, there are substances like some nitrofurane derivatives for which the presence of particular molecular structures is the decisive condition. Thus, a nitrofurane derivative prepared by Casini and his co-workers (87) has shown bacteriostatic properties similar to classical low molecular preparations of nitrofurane, e.g. l-[5-(nitrofurfuryliden)amino]hydantoine. The polymeric substance shows an activity considerably longer than that of the reference substance if parenterally applied, whereas oral application gives no effect. This is easy to understand because, as already mentioned, polymers cannot be resorbed in the digestive tract. Here, the active polymeric substance [22] has been prepared by condensation of 5-nitrofuraldehyde with poly(acryloylhydrazide). [Pg.39]

Peaks of essentially the same shape and, therefore, derived from the same species, were observed for mle = 48, 44, 46, 30, 18, and 4 between 500 and 600 K for d6-PC condensed on Ag(poly) surfaces prepared under the same conditions described in the previous subsection for Au(poly). [Pg.243]

Poly amines prepared by Koch [4] were converted into the corresponding isocyanate derivatives, (I), using phosgene methylenebis(phenyl isocyanate) was prepared by Strofer [5]. [Pg.385]

Yasuda, T. et al.. Organic field effect transistors with gate dielectric films of poly-p-xylylene derivatives prepared by chemical vapor deposition, Jpn. J. Appl. Phys. 42, 6614-6618, 2003. [Pg.251]

Substituted PPVs are soluble in organic solvents, which is a very useful feature in the preparation of polymer LEDs. One of the first PPV soluble derivatives, prepared by the Santa Barbara group in California via the precursor route, was methoxy-ethylhexyloxy PPV (MEH-PPV), which emitted a red-orange color [107,108]. Subsequently another PPV derivative with the bulky cholestanoxy group was prepared, namely the poly [2,5-bis(3a-5b cholestanoxy)-1,4-pheny-lene vinylene] (BCHAPPV). A blue shift was observed in relation to MEH-PPV BCHA-PPV emitted in the yellow region [109,110]. [Pg.761]

This review presents the syntheses of different analogs of sucrose. Transformations of this di-saccharide at the terminal positions (Cl, or C6, or C6 ) provide modified sucroses such as amines, uronic acids, thiols, or phosphorus derivatives. Preparation of so-called higher sucroses i.e. derivatives in which the terminal positions are elongated by a poly-hydroxylated carbon chain is also reviewed. Special attention is directed to the synthesis and properties of macrocyclic derivatives crown- and aza-crown ethers with sucrose scaffold. Such macrocyclic receptors exhibit interesting complexing properties towards chiral ammonium salts. [Pg.260]

The thermal polymerization of -MeOSt has already been mentioned by Staudinger and Dreher [239]. Heating a bulk sample to 90 °C for several days yielded a polymer with a DP = 390 (by viscosity measurements). Later, Russian authors [269] polymerized thermally all three isomers at 100 to 125 °C and found the p and m isomers to polymerize less rapidly than styrene, but the o isomer more rapidly. The stereoregularity of poly(/ -MeOSt) prepared by thermal polymerization in bulk at 60 °C was examined by Yuki et al. [270]. 100-MHz H-NMR spectra showed a rather split signal for the methoxy group and was interpreted in terms of pentad sequences. The analysis of the thermally polymerized sample showed a rather low content of syndiotactic triads. Kawamura et al. [244] studied the C-NMR spectra of o- and -MeOSt polymers prepared with BPO in toluene at 80 °C. They found both polymers to be rich in syndiotactic sequences [o derivative,, = 0.80 p derivative, P = 0.1 (P, = probability of racemic addition of monomer to the growing chain)]. [Pg.113]

Di- and poly-halogenated aliphatic hydrocarbons. No general procedure can be given for the preparation of derivatives of these compounds. Reliance must be placed upon their physical properties (b.p., density and refractive index) and upon any chemical reactions which they undergo. [Pg.292]

Suitable protective coUoids for the preparation of acryhc suspension polymers include ceUulose derivatives, polyacrylate salts, starch, poly(vinyl alcohol), gelatin, talc, clay, and clay derivatives (95). These materials are added to prevent the monomer droplets from coalescing during polymerisation (110). Thickeners such as glycerol, glycols, polyglycols, and inorganic salts ate also often added to improve the quahty of acryhc suspension polymers (95). [Pg.169]

Decafluorobiphenyl [434-90-2] C F C F (mol wt, 334.1 mp, 68°C bp, 206°C), can be prepared by I Jllmann coupling of bromo- [344-04-7] chloro- [344-07-0] or iodopentafluorobenzene [827-15-6] with copper. This product shows good thermal stabiHty decafluorobiphenyl was recovered unchanged after 1 h below 575°C (270). Decafluorobiphenyl-based derivatives exhibit greater oxidative stabiHty than similar hydrocarbon compounds (271). Therm ally stable poly(fluorinated aryl ether) oligomers prepared from decafluorobiphenyl and bisphenols show low dielectric constant and moisture absorption which are attractive for electronic appHcations (272). [Pg.328]

Derivatives of hemicellulose components have properties similar to the ceUulosic equivalents but modified by the effects of thek lower molecular weight, more extensive branching, labile constituents, and more heterogeneous nature. Acetates, ethers, carboxymethylxylan (184), and xylan—poly(sodium acrylate) (185) have been prepared. [Pg.34]

Emulsions of fatty- and petroleum-based substances, both oils and waxes, of the o/w type are made by using blends of sorbitan fatty esters and their poly(oxyethylene) derivatives. Mixtures of poly(oxyethylene(20)) sorbitan monostearate (Polysorbate 60) and sorbitan monostearate are typical examples of blends used for lotions and creams. Both sorbitan fatty acid esters and their poly(oxyethylene) derivatives are particularly advantageous in cosmetic uses because of their very low skin irritant properties. Sorbitan fatty ester emulsifiers for w/o emulsions of mineral oil are used in hair preparations of both the lotion and cream type. Poly(oxyethylene(20)) sorbitan monolaurate is useflil in shampoo formulations (see Hairpreparations). Poly(oxyethylene) sorbitan surfactants are also used for solubilization of essential oils in the preparation of colognes and after-shave lotions. [Pg.54]

The thermal glass-transition temperatures of poly(vinyl acetal)s can be determined by dynamic mechanical analysis, differential scanning calorimetry, and nmr techniques (31). The thermal glass-transition temperature of poly(vinyl acetal) resins prepared from aliphatic aldehydes can be estimated from empirical relationships such as equation 1 where OH and OAc are the weight percent of vinyl alcohol and vinyl acetate units and C is the number of carbons in the chain derived from the aldehyde. The symbols with subscripts are the corresponding values for a standard (s) resin with known parameters (32). The formula accurately predicts that resin T increases as vinyl alcohol content increases, and decreases as vinyl acetate content and aldehyde carbon chain length increases. [Pg.450]


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See also in sourсe #XX -- [ Pg.32 ]




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Derivatives, preparation

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Poly derivatives

Poly prepared

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