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Ethylene glycol structure

Jiang, H. Manolache, S. Wong, A. C. Denes, F. S., Synthesis of Dendrimer-Type Poly(ethylene glycol) Structures from Plasma-Functionalized Silicone Rubber Surfaces. J.Appl. Polym. Sci. 2006,102, 2324-2337. [Pg.140]

This synthetic strategy is based on the formation of direct micelles of Pluronic FI 27 in water. Pluronic FI 27 is a non-ionic triblock copolymer surfactant terminating in primary hydroxyl groups, and presenting a poly(ethylene glycol)-poly (propylene oxide)-poly(ethylene glycol) structure (PEG-PPO-PEG, MW 12600), that is relatively non-toxic. [Pg.108]

Polymerisation of a diol with a dicarboxybe acid is exemplified by the production of a polyester from ethylene glycol and terephthabc acid either by direct esterification or by a catalysed ester-interchange reaction. The resulting polyester (Terylene) is used for the manufacture of fibres and fabrics, and has high tensile strength and resibency its structure is probably ... [Pg.1019]

Poly(ethylene Terephthalate). Poly(ethylene terephthalate) is prepared by the reaction of either terephthalic acid or dimethyl terephthalate with ethylene glycol, and its repeating unit has the general structure. [Pg.1019]

To some extent each of these objections is met by the presence of either chemical or crystallite crosslinking in the polymer. Another approach which complements the former is to incorporate rings into the backbone of the chemical chain. As an example, contrast the polyesters formed between ethylene glycol and either suberic or terephthaUc acid. Structures [V] and [VI], respectively, indicate the repeat units in these polymers ... [Pg.334]

The sodium or potassium salt of 6-azauracil in aqueous ethanol, anhydrous ethanol, or ethylene glycol reacted with methyl iodide practically exclusively to give the 3-methyl derivative (63). In toluene the sodium, potassium, and mercuric salts produced no methylated derivatives whereas the silver salt also yielded the 3-methyl derivative, Similarly, the 3-methyl derivative was prepared from the mercuric salt of 6-azathymine, and its structure was established by hydrolysis to pyruvic acid 4-methylthiosemicarbazone. ... [Pg.211]

A different type of tautomeric relationship exists between compounds of types 323 and 324. Both types of structure can be isolated, pyridones (324, Z = N—Me) and pyrones (324, Z = 0) being formed when 323 (Z = N—Me or 0) is heated with palladium on charcoal in ethylene glycol. Similar isomerizations in the quinol-4-one series have been reported."... [Pg.432]

It is prepared by reaction of ethylene glycol with 1,4-benzenedicarboxylic acid (tere-phthalic acid). Draw the structure of PET. [Pg.1214]

Write the structure of a representative segment of polyurethane prepared by reaction of ethylene glycol with MDI (Problem 31.29). [Pg.1224]

Write the structural formulas of all the esters that can be formed by ethylene glycol with formic and acetic acids. (One or both of the —OH groups of ethylene glycol can react.)... [Pg.608]

Ethylene glycol has empirical formula CH30 and molecular formula C2H602. Using the usual bonding rules (carbon is tetravalent oxygen is divalent hydrogen is monovalent), draw some of the structural formulas possible for this compound. [Pg.329]

Decide which of your structures in Exercise 18-4 best fits the following list of properties observed for pure ethylene glycol. [Pg.329]

Figures 15 and 16 demonstrate folding in the l,l,l,3,3,3-hexafluoro-2-propanol/ethylene glycol (HFP/EG) mixture (1 2) and in 1,3-propandiol in comparison to Fig. 13, which describes helix formation in water. The structure formation is much more pronounced. This is indicated by the more negative signals of the CD spectrum at 198 nm. The negative values of 0 for the octamer increase from -1.8 x 10-4 deg cm2 dmol-1 in... Figures 15 and 16 demonstrate folding in the l,l,l,3,3,3-hexafluoro-2-propanol/ethylene glycol (HFP/EG) mixture (1 2) and in 1,3-propandiol in comparison to Fig. 13, which describes helix formation in water. The structure formation is much more pronounced. This is indicated by the more negative signals of the CD spectrum at 198 nm. The negative values of 0 for the octamer increase from -1.8 x 10-4 deg cm2 dmol-1 in...
Polyesters are another important class of polyols. There are many polyester types used, so a generic structure is shown in Scheme 4.4. They are often based on adipic acid and either ethylene glycol (ethylene adipates) or 1,4-butanediol (butylene adipates). Polyesters, because of the polar carbonyl groups, contribute more to intermolecular forces, and physical properties such as tear and impact resistance are often improved by using them. They are also utilized for their solvent and acid resistance and light stability. Relatively poor hydrolytic stability is... [Pg.212]

Write the condensed structural formulas of the principal products of the reaction that takes place when (a) ethylene glycol, 1,2-ethanediol, is heated with stearic acid, CH,(CH2)i6COOH (b) ethanol is heated with oxalic acid, HOOCCOOH (c) 1-butanol is heated with propanoic acid. [Pg.901]

Random condensation copolymers can be formed by adding a third monomer to the reaction mix. For example, some 1,4-butanediol might replace some of the ethylene glycol in a PET polymerization. Suppose the three monomers are AMA, BNB, and BZB. The resulting polymer will have a structure such as... [Pg.467]

Dynamic light-scattering experiments or the analysis of some physicochemical properties have shown that finite amounts of formamide, A-methylformamide, AA-dimethyl-formamide, ethylene glycol, glycerol, acetonitrile, methanol, and 1,2 propanediol can be entrapped within the micellar core of AOT-reversed micelles [33-36], The encapsulation of formamide and A-methylformamide nanoclusters in AOT-reversed micelles involves a significant breakage of the H-bond network characterizing their structure in the pure state. Moreover, from solvation dynamics measurements it was deduced that the intramicellar formamide is nearly completely immobilized [34,35],... [Pg.476]

Kan et al. reported preparation of Au-core/Pd-shell bimetallic nanoparticles by successive or simultaneous sonochemical irradiation of their metal precursors in ethylene glycol, respectively. In the successive method, Pd clusters or nanoparticles are first formed by reduction of Pd(N03)2, followed by adding HAUCI4 solution. As a result, Au-core/Pd-shell structured particles are formed, although Pd-core/Au-shell had been expected. In their investigations, the successive method was more effective than the simultaneous one in terms of the formation of the Au-core/Pd-shell nanoparticles [143]. [Pg.56]

Draw the structural formula for the polymer that you will prepare from phthalic anhydride and ethylene glycol. [Pg.182]

The mobilities of alkylpyridines were modeled and predicted in capillary zone electrophoresis.35 The model predicted that compounds adopt a preferred orientation, and additionally predicted mobilities of structural isomers to within 4%, a higher degree of accuracy than can be obtained from simple considerations of van der Waal s radius. Quantitative prediction of the mobilities of some pyridines, such as alkenylpyridines, was not possible. Mobilities of small solutes in capillaries filled with oligomers of ethylene glycol were related to solution viscosity and the diffusion coefficient.36... [Pg.430]

Although less common than zinc chlorides, there has been much synthetic and structural work carried out on zinc bromide and iodide complexes. For example, the 1 1 adduct of N,N,N, A -tetramethyl-o-phenylenediamine with zinc bromide has been structurally characterized.630 The ion exchange properties of zinc bromide and iodide have been studied in ethylene glycol.631 The electrolytic behavior of zinc bromide in propylene carbonate has been studied and the conductance data shows the existence of dimers.632... [Pg.1201]

In the ethylene glycol inclusion of 1, the channel structure cannot be detected any longer. An explanation is found in the fact that the gracile guest molecule,... [Pg.114]


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See also in sourсe #XX -- [ Pg.319 ]




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