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Epoxides physical properties

In general, the peilluoioepoxides have boiling points that are quite similar to those of the corresponding fluoroalkenes. They can be distinguished easily from the olefins by it spectroscopy, specifically by the lack of olefinic absorption and the presence of a characteristic band between 1440 and 1550 cm . The nmr spectra of most of the epoxides have been recorded. Litde physical property data concerning these compounds have been pubhshed (Table 1). The stmcture of HFPO by electron diffraction (13) as well as its solubility and heats of solution in some organic solvents have been measured (14,15). [Pg.301]

Table 5. Physical Properties of Black-Filled Epoxidized Natural Rubber ... Table 5. Physical Properties of Black-Filled Epoxidized Natural Rubber ...
A symmetry boundary condition was imposed perpendicular to the base of the mold. Since the part is symmetric, only half of the part cross-section needed to be simulated. The initial conditions were such that resin was at room temperature and zero epoxide conversion. The physical properties were computed as the weight average of the resin and the glass fibers. [Pg.261]

Many physical and process constraints limit the cycle time, where cycle time was defined as the time to the maximum exotherm temperature. The obvious solution was to wind and heat the mold as fast and as hot as possible and to use the polymer formulation that cures most rapidly. Process constraints resulted in a maximum wind time of 3.8 minutes where wind time was defined as the time to wind the part plus the delay before the press. Process experiments revealed that inferior parts were produced if the part gelled before being pressed. Early gelation plus the 3.8 minute wind time constrained the maximum mold temperature. The last constraint was based upon reaction wave polymerization theory where part stress during the cure is minimized if the reaction waves are symmetric or in this case intersect in the center of the part (8). The epoxide to amine formulation was based upon satisfying physical properties constraints. This formulation was an molar equivalent amine to epoxide (A/E) ratio of 1.05. [Pg.267]

Hydronium ion, 14 23 Hydroperoxidates, 18 411 Hydroperoxide process, for propylene oxide manufacture, 20 798, 801-806 Hydroperoxides, 14 281, 290-291 18 427-436 alkylation of, 18 445 a-oxygen-substituted, 18 448-460 chemical properties of, 18 430 433 decomposition of, 14 279 18 431-432 liquid-phase epoxidation with, 10 656 physical properties of, 18 427-430 preparation by autoxidation, 18 434 synthesis of, 18 433-435 Hydrophile-lipophile balance system,... [Pg.456]

Thorat SD, Phillips PJ, Semenov V, Gakh A (2003) Physical properties of aliphatic polycarbonates made from CO2 and epoxides. J Appl Polym Sci 89 1163-1176... [Pg.46]

Regeneration of spent reagent is easy, and no loss in peroxide content is seen even over several recycles. Physical properties of the material are essentially unchanged. Labile epoxides, such as the industrially important a-pinene oxide can also be prepared in good yield under relatively mild conditions. This may be attributed to the heterogeneous nature of the system, which means that the solution phase is non-acidic. [Pg.279]

The present chapter will be devoted to the chemistry of epoxides, and will be divided into five principal sections. These wifi deal respectively with the following topics I, physical properties H. occumenee in nature ID, synthesis IV, chemical reactions V, analytical methods. [Pg.8]

To date this question apparently remains unresolved, although the physical properties reported for the two supposed epoxides are different... [Pg.149]

The detectability (1) of hydrocarbon pesticides varies because of their differing chemical structure and physical properties. The practical minimum limits of analysis by this procedure are (a) 10 p.p.t. or less for aldrin, DDD, DDT, dieldrin, endrin, heptachlor, heptachlor epoxide,... [Pg.205]

Previous Investigations of the cure kinetics In this system have either emphasized the changes In physical properties such as loss modulus and viscosity of the medium or chemical properties such as the concentration of epoxide or amine functionalities at various stages of cure.(1-7) In several earlier reports, we attempted to derive an overall mechanistic picture for this system which would recognize constraints due to both changing reactivity as well as Increasing viscosity.(8-10)... [Pg.83]

To overcome these drawbacks, in recent years much attention has been paid to the development of resins which cem be f2d ricated with the same processes as those for conventional polyester resins, but having superior properties. Vinyl ester resins are the result of such development efforts (4-6). Vinyl ester resins are addition products of Vcurious epoxide resins and ethylenically unsaturated mono-carboxylic acids ( ). It condsines the excellent mechcuiical, chemical cuid solvent resistemce of epoxy resins with the properties found in the unsaturated polyester resins. In general, the cured vinyl ester resin has physical properties superior to the cured conventional ester resin, particulcurly corrosion resistcuice. This arises from the differences in the number and arremgement of polar groups such as ester and hydroxyl groups eind ccurbon-to-ccirbon double bonds present in the polymer chains. [Pg.202]

How these factors affect the physical properties of alcohols, ethers, and epoxides is summarized in Table 9.1. [Pg.320]

Epoxidation of the cis alkene A from two different sides of the double bond affords two cis epoxides in the last step—a racemic mixture of two enantiomers. Thus, half of the product is the desired pheromone disparlure, but the other half is its biologically inactive enantiomer. Separating the desired from the undesired enantiomer is difficult and expensive, because both compounds have identical physical properties. A reaction that affords a chiral epoxide from an achiral precursor without forming a racemic mixture is discussed in Section 12.15. [Pg.441]


See other pages where Epoxides physical properties is mentioned: [Pg.32]    [Pg.32]    [Pg.301]    [Pg.553]    [Pg.209]    [Pg.309]    [Pg.118]    [Pg.354]    [Pg.35]    [Pg.578]    [Pg.936]    [Pg.274]    [Pg.13]    [Pg.72]    [Pg.132]    [Pg.156]    [Pg.136]    [Pg.415]    [Pg.144]    [Pg.333]    [Pg.379]    [Pg.265]    [Pg.234]    [Pg.99]    [Pg.321]    [Pg.144]    [Pg.60]   
See also in sourсe #XX -- [ Pg.32 , Pg.320 ]

See also in sourсe #XX -- [ Pg.318 , Pg.318 ]




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Epoxides properties

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