Estimation of Compatibility

A more quantitative estimation of compatibility can be obtained with the solvent cloud point test. The solvent cloud point is based on the idea that resins will be compatible with elastomers of similar chemical nature. Thus aliphatic resins will be effective tackifiers for aliphatic elastomers, such as natural rubber, while aromatic solvents are needed for aromatic elastomers, such as SBR. Solvent cloud point tests are carried out in three solvent systems which represent aliphatic, aromatic, or polar systems [16j ... 

These effects are part of the solubility parameters concept. This concept allows to predict compatibility qualitatively (see Section 6.2). Within the framework of the general principles of the thermodynamics of solutions, the numerical evaluation of compatibility implies the evaluation of the value of the free energy (the Gibbs energy) of mixing over the whole range of solution concentration. However, sueh evaluations are difBcult and often excessive for most practical purposes. Therefore, for the estimation of compatibility, it is more convenient to know the value of aity numerical criterion mentioned in the previous subchapters. 

The solubiHty parameter of a polymer is a measure of its iatermolecular forces, and provides an estimate of the compatibiHty of a polymer with another polymer or a polymer with a solvent. Two components are compatible if they have similar solubiHty parameters. The solubiHty parameter can be determined by various methods, such as intrinsic viscosity and swelling measurements. The solubiHty parameters of various polymers and solvents are tabulated ia refereace handbooks (146,147). It also can be estimated from the stmcture of the polymer (148). 

A partial check list of operations for an industrial chemical laboratory is shown in Table 1. The format of a formal list will vary considerably from one laboratory to another, but with such an aid, one can easily see which operations are compatible and then group these together. Those that need special treatment will readily stand out. The planner will also be able to estimate the number of rooms required for the total operation. Finally, a complete list of all laboratory functions will facilitate the next step, an estimate of space requirements. 

Rate laws and coefficients were determined for the oxidation of all intermediate compounds by MnOJ and were compatible with the scheme as presented, i.e. including a route for direct oxidation to pyruvaldehyde. An estimate of k2 ( 5x10 l.mole sec ) suggests an initial electron-transfer to give CH3 COCH2 . This can then be rapidly oxidised in two ways... 

There are several reasons why the coming age will see a dominance of biomass as renewable energy source. This in essence relates to compatibility with existing conversion technology. This is highlighted by a recent estimate of investments needed when traditional energy are substituted by alternative resources (Fig. 1.10). 

Note 1 Estimates of the degree of compatibility are often based upon the mechanical performance of the composite, the interphase thickness, or the sizes of the phase domains present in the composite, relative to the corresponding properties of composites lacking compatibility. 

Note that, as is easily observed from b.v.p.(6.4.45)-(6.4.55), with a concentration gradient present no unidirectional developed Poiseuille-type channel flow is compatible with the boundary conditions (6.4.51). A fairly complicated two-dimensional flow pattern is thus generally expected even away from the edges of the channel. The appropriate rigorous flow calculation is still to be done. Here we shall content ourselves with the following crude order of magnitude estimate of the contribution of the above-mentioned circulation to the solute transport through the channel. 

The third column gives an approximate estimate of the standard error of the excess reduction, taking into account only statistical variations. The final column of Table 7.4 gives the excess reductions in terms of PbB. Since a reduction in petrol lead of 60% gave a reduction in PbB of exposed men and women of 4%, the conclusion might be drawn that lead in petrol contributed 7% of PbB before the reduction. Similarly, for traffic police and children, it contributed 20% and 16% respectively. These results are broadly compatible with the results of the Isotopic Lead Experiment, taking into account the special factors tending to increase exposure to PbA in Turin. 

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