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A surface tension theory is developed for application to systems containing polydisperse polymers and using the Bronsted congruence principle for quantitative description of the thermodynamic functions of mixtures of homologues on the basis of the quasi-solution principle as applied to an homologuous polymer series. The alternative equilibrium conditions as between the homogeneous phase and a surface layer of finite thickness are described for concentrated polymer solutions. One of these conditions assumes that the chemical potentials of the macromolecules are equivalent, and another that the chemical potentials of the components of the quasi-solution (units and end groups) are equivalent. On realization of the second absorption mechanism the segregation of micromolecules by MM in the surface layer is eliminated. The feasibility of experimental checking of the conclusions from the theory is discussed.

Publisher Summary This chapter formulates the principles of geodynamics and geotectonics—acting forces and evolutionary factors in the universe and within the interior of the earth. The basic theses of system geotectonics that fundamentally solve the key problems of geology generates protean concepts concerning cyclic processes involved in the evolution of the earth. The galaxy, the Sun, and planets are rotating and pulsating, and the vectors of lunar–solar influences are moving over the earth cyclically and with the intervals of celestial mechanics. Lithospheric plates and platforms are reciprocally colliding, rifts are opening, mobile belts are migrating, and the ridges of transcontinental geotectonic belts are rising. Convective plumes are continually emerging from the pulsating mantle below the transoceanic geotectonic belt and astenospheric flows are moving below the lithosphere. At certain times, the areas of diffuse-linear spreading and volcanism have appeared, expanded, and then later contracted. Following this contraction, the fronts of ocean formation moved and created oceans. Contemporaneously with the submergence of the dehydrated oceanic lithosphere, granitized continents incremented by astenospheric subduction are emerging. A cyclically transformed lithosphere oscillates, but remains integral. It reflects deep changes of the increasingly eccentric heterogeneous earth, living solar and galactic years during its life, which are imprinted in the sedimentary record and biostratigraphic scale. The evidence of a logical unity of immutability and mutability, rest and motion, embodied in the inherited evolution of the planetary crust, affirms the replacement of the geocentric geotectonics by another that is cosmogenous–endogenous.

Mixtures of polyxypropylene polyols with water are typical systems with a lower critical miscibility temperature whose position is proportional to the concentration of end hydroxyl groups independently of the degree of branching of the polyethers. Replacement of low-molecular products with water. The polydispersity of the specimens of the polyoxypropylene polyols has a substantial effect on the phase diagrams, whose shapes are principally determined by the presence of the high-molecular fractions.

The chemical equilibrium in the synthesis of poly(butylene-glycol adipate) was studied experimentally, and the heat effect of the process was determined. A comparison was made of the equilibrium thermodynamic parameters (equilibrium constant, enthalpy of the process) as calculated by means of the equilibrium equation in terms of the thermodynamic theory of linear polycondensation, and by means of the simple kinetic equation of equilibrium. It is shown that the new theory better describes the experimental data.

Differential equations for the surface tension as a function of temperature, pressure, and composition of a two-phase system containing linear macromolecules are derived within the framework of the quasi-solution theory. An alternative version of the theory has been developed for concentrated solutions and melts, in which the units and end groups are considered to be mobile components. Analysis shows that the existence of selective adsorption of chain units or end groups in the surface layer cannot be established simply on the basis of data on the surface tension in an homologous series. The feasibility of observing this hypothetical effect in measurements on the equilibrium elasticity of thick films of liquid polymer homologues is discussed.

Concentration dependences of the excess volume of mixing have been derived for mixtures of liquid homologues belonging to the same polymer-homologous series and also for homolog mixtures containing members of homomorphous series. The obtained functions have been analysed quantitatively using experimental data on the volume of mixing of higher linear alkanes, alkanols, and 1-chloroalkanes. The theory agrees with experiment for sufficiently long molecules. The lowest chain length limiting the range of applicability of the quasi-solution concept depends on the character of end groups.

On the basis of the concept of a quasisolution and the Bronsted principle of congruence the authors have obtained fundamental equations for the Gibbs energy of a polydisperse polymer in which the units of the chain molecules and their terminal groups act as independent components of the system including the general case of the presence of any other substances. From analysis of the chemical potentials of the units and the terminal groups they infer the equivalence of the congruence principle and the Flory principle on the indistinguishability of these components in the same or different macromolecules. The use of the equations obtained for describing chemical equilibrium on polycondensation of bifunctional monomers is examined. Where necessary it is easy to bring the system investigated into line with the Flory principle if the lower homologues differing in reactivity are brought into the category of extraneous substances-comonomers, the mathematical apparatus of the theory remaining unchanged.

It is proposed that an infinite sequence of linear polymer homologues be described as an open thermodynamic system whose equilibrium state is characterized by an additional parameter, i.e. by the length of macromolecules. This idea has led to the derivation of basic equations for the energy of a system: the repeat-units of chain molecules and the endgroups figure as independent components, like other substances present in the system. An analysis of the phase equilibria led to the derivation of an analogue of the known generalized differential van der Waals equation.

The temperature dependence of the viscosity of linear polypropylene glycols (PPG) of various mol.wt. was studied in the range from −50 to +50°C, amongst them that of a sample in which the hydroxyl end groups had been substituted by methyl groups. The temperature-viscosity functions of all the samples were found to be described by the Williams-Landell-Ferri empirical formula. The type of dependence in this formula of the parameters on the mol.wt. and the hydroxyl group content of the PPG was well explained by the theories dealing with the relaxation processes as a consideration of the free volume.