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Chain length and distribution

More precise molecular weight development chain length and distribution. [Pg.18]

The choice of the polymer plays a role, for instance, in the chain length and distribution, in orientations, and in the various process variables (injection pressure and temperature, afterpressure, mold temperature). [Pg.458]

The hydrophile can vary in terms of EO chain length and distribution (conventional vs. peaked ). This give this nonionic class significant flexibility in meeting a wide range of physical property and performance criteria. [Pg.302]

In the case of HM-polymers abundant evidence exists that the alkyl groups in the dissolved polymer can be preassociated. This means that centers will be provided for the adsorption/association of surfactant ions (and molecules). Their composition and size will change with surfactant concentration, as will their nature—intermolecular and/or intramolecular. Fine points in this case include the number, type, chain length, and distribution of hydrophobic groups and, again, the detailed structure of the base polymer. In fact, the number of possible variations on this structural theme is vast ... [Pg.189]

Determination of the type, amount, and distribution of alkyl mono-and oligoglycosides and the alkyl chain length and distribution of the fatty alcohol bound in the product. The average DP is calculated from these data. [Pg.41]

The urea—formaldehyde reaction results in a distribution of methylene urea (MU) polymers of varying molecular weights or polymer chain lengths and of varying water solubiUty. [Pg.130]

In actual practice, the reaction of urea with formaldehyde produces a distribution of polymers of varying chain length. The distribution is affected by the U/E mole ratio as well as reaction conditions such as pH, temperature, and reaction time. In general, higher U/E ratios produce polymer distributions... [Pg.131]

In some of these models (see Sec. Ill) the surfactants are still treated as flexible chains [24]. This allows one to study the role of the chain length and chain conformations. For example, the chain degrees of freedom are responsible for the internal phase transitions in monolayers and bilayers, in particular the hquid/gel transition. The chain length and chain architecture determine the efficiency of an amphiphile and thus influence the phase behavior. Moreover, they affect the shapes and size distributions of micelles. Chain models are usually fairly universal, in the sense that they can be used to study many different phenomena. [Pg.638]

The effect of carbon chain length and high vs. low 2-phenyl isomer distribution on viscosity and solubility (cloud/clear point) of a liquid hand dishwashing formulation is shown in Table 5. Two sets of pure LAS homolog samples ranging from Cl0 to Cl3 were prepared. All samples were prepared with pure olefins, but one set was produced with an HF alkylation catalyst (low 2-phenyl) and the other set was alkylated with A1C13 (high 2-phenyl). Each LAB... [Pg.119]

Alkanesulfonates are the petrochemically derived sulfur analogs of soaps, which are alkane carboxylates based on renewable resources. The main difference between alkanesulfonates and soaps is, however, that alkanesulfonates consist of a rather complex mixture of homologs with different carbon chain lengths and isomers with an almost statistical distribution of the functional group along the hydrophobic carbon chain (Fig. 1), whereas soap is a mixture of homologs of alkane 1-carboxylates with an even number of carbon atoms. [Pg.144]

For long linear chains the second condition is supported by the Stockmayer bivariate distribution (8,9) which shows the bivariate distribution of chain length and composition is the product of both distributions, and the compositional distribution is given by the normal distribution whose variance is inversely proportional to chain length. [Pg.243]

Because any given polymer sample contains a distribution of different chain lengths and branching, any enthalpy of polymerization values reported will be an average value. Also, no polymerization reaction proceeds fully to completion. Instead, the reaction stops when an equilibrium is established, leaving a mixture of components with a range of concentrations. These variables lead to the approximate nature of enthalpy of polymerization values. [Pg.71]

Theoretically, if each molecule in a polymer sample were to be linked to two of its neighbors, a single highly branched molecule would form that would encompass the whole sample. In practice, due to the statistical distribution of chain lengths and the random incorporation of crosslinks, the situation is far more complex. [Pg.117]

The solute used in Fig. 18.4 had a fixed alkyl chain length, and as the alkyl distribution increases, one-dimensional NPLC separations become more complex. In Fig. 18.5 the amino silica chromatograms of Novel II1412-70 and Neodol 25-12 are shown, and their corresponding chemical compositions are given in Table 18.2 along with other AE s. [Pg.432]

Several factors indicate that the amino acids detected in all of these carbonaceous chondrites are indigenous and that they must have originated abiotically. First, the presence of protein and non-protein amino acids, with approximately equal quantities of D and L enantiomers points to a nonbiological origin and precludes terrestrial contamination. In addition, the non-extractable fraction of the Murchison is significantly heavier in 13C than terrestrial samples. Finally, the relative abundances of some compounds detected resemble those of products formed in prebiotic synthesis experiments. The aliphatic hydrocarbons are randomly distributed in chain length, and the C2, C3, and C4 amino acids have the highest concentrations (i.e., the most easily synthesized amino acids with the least number of possible structures are most abundant) [4]. [Pg.391]


See other pages where Chain length and distribution is mentioned: [Pg.431]    [Pg.672]    [Pg.26]    [Pg.213]    [Pg.142]    [Pg.2223]    [Pg.35]    [Pg.169]    [Pg.44]    [Pg.431]    [Pg.672]    [Pg.26]    [Pg.213]    [Pg.142]    [Pg.2223]    [Pg.35]    [Pg.169]    [Pg.44]    [Pg.140]    [Pg.446]    [Pg.315]    [Pg.360]    [Pg.152]    [Pg.449]    [Pg.251]    [Pg.272]    [Pg.402]    [Pg.235]    [Pg.321]    [Pg.40]    [Pg.117]    [Pg.162]    [Pg.485]    [Pg.86]    [Pg.110]    [Pg.16]    [Pg.321]    [Pg.138]    [Pg.73]    [Pg.23]    [Pg.68]    [Pg.350]    [Pg.192]   
See also in sourсe #XX -- [ Pg.26 , Pg.31 ]




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Length distribution

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