Subject Stockmayer

The ring-opening polymerization of is controUed by entropy, because thermodynamically all bonds in the monomer and polymer are approximately the same (21). The molar cycHzation equihbrium constants of dimethyl siloxane rings have been predicted by the Jacobson-Stockmayer theory (85). The ring—chain equihbrium for siloxane polymers has been studied in detail and is the subject of several reviews (82,83,86—89). The equihbrium constant of the formation of each cycHc is approximately equal to the equihbrium concentration of this cycHc, [(SiR O) Thus the total... 

The problem of the influence of intramolecular interactions on the configurations of polymer molecules has been the subject of much controversy, which need not be reviewed here. For treatment of the problem by methods other than the one presented in the following pages, the reader is referred to papers by F. Bueche, J. Chem. Phys., 21, 205 (1953), and B. H. Zimm, W. H. Stockmayer, and M. Fixman, J. Chem. Phys., 21, 1716 (1953). These papers include references to other literature on the subject. 

In the 1940s and 1950s, random branching in polymers and its effect on their properties was studied by Stockmayer, Flory, Zimm and many others. Their work remains a milestone on the subject to this day. Flory dedicated several chapters of his Principles of Polymer Chemistry to non-linear polymers. Especially important at that time was the view that randomly branched polymers are intermediates to polymeric networks. Further developments in randomly branched polymers came from the introduction of percolation theory. The modern aspects of this topic are elaborated here in the chapter by W. Burchard. 

This article deals with one of the above mentioned subjects already treated in the 1940 s branched polymers. We present a survey of a number of scattering functions for special branched polymer structures. Hie basis of these model calculations is still the Flory-Stockmayer (FS) theory1,14,15) but now endowed with the more powerful technique of cascade theory which greatly simplifies the calculations. 

One of the most important phenomena in the polymer solvation is the change in the overall size of the polymer chain upon solvation. In fact at equilibrium the average size of isolated polymer molecules in solution is a function of solvent quality and varies from expanded conformations in good solvents to random walk conformations in poor solvents. This is referred to as collapse transition and was first predicted by Stockmayer [82] more than 45 years ago. The phenomenon was observed by Nishio et al. [83] and Swislow et al. [84] more than 25 years ago and is still a subject of much experimental, computational, and theoretical research today. So far many investigators have tried to study the chain size with solvation using a variety of methods. 

Non-central Potential Functions.—Non-central interactions can also be handled in terms of specific multi-parameter potential functions such as the Stockmayer and Kihara potentials. Although there is an extensive literature on the subject of such potentials, it is only rarely that virial coefficients are sufficiently precise or extensive to warrant their use. For this reason we will deal only briefly with the subject. 

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