Pair interactions, poly

Schlitzer, D. S. Novak, B. M. Trapped Kinetic States, Chiral Amplification and Molecular Chaperoning in Synthetic Polymers Chiral Induction in Poly guanidines through Ion Pair Interactions, J. Am. Chem. Soc. 1998, 120, 2196-2197. 

Several excellent articles review homonuclear main-group clusters. In this article we will concentrate on homoatomic polyhedral clusters of the elements Ge, Sn, and Pb with special emphasis on the relationship between soluble and linked clusters, and on certain physical properties. For these elements, several soluble anions and polymeric solid structures with different valence concentrations are known. In the first part attention is turned to structures and properties of isolated molecular clusters synthesized by solution methods. In the second part, linked poly-hedra and the increased formation of lone pairs with increasing valence-electron concentration in solid-state compounds is discussed. The influence of lone-pair interactions on electronic structures and on the superconductivity found in some of the compounds will also be discussed. Related aspects of compounds containing elements adjacent to Ge, Sn, and Pb in the periodic table are mentioned. 

Kambour RP, Bendler JT, Bopp RC (1983) Phase behavior of polystyrene, poly(2,6-dimethyl-l,4-phenylene oxide), and their brominated dtaivatives. Macromolecules 16 753-757 Koningsveld R, Kleijens LA (1971) Liquid-liquid phase separation in multicomponent polymer systems. X. Concentration dependence of the pair-interaction parameter in the system cyclohexane-polystyrene. Macromolecules 4 637-641 Maron SH (1959) A theory of the thermodynamic behavior of non-electrolyte solutions. J Polym Sci 38 329-342... 

The classic rigid lattice model still proves to be a valuable tool for predictive calculations of phase stability in polymer blends. It depends on the required accuracy whether the simple model needs improvement. Miscibility behaviour of blends containing statistical copolymers do not seem to require such Improvements since values of pair-interaction parameters obtained on one system appear to be transferable to another, fig.6 bears witness of this welcome feature. A similar transferability was observed previously in an analysis of critically demixing poly(styrene) solutions in n-alkanes and n-alcohols varying in number of carbon atoms [31]. The data allowed extraction of the end/middle group interaction function for n-alkanes that correctly predicted the lower critical miscibility behavior of n-alkane /poly(ethylene) systems. 

The effective pair interactions measured with these techniques are the direct pair interactions between two colloidal particles plus the interactions mediated by the depletants. In practice depletants are poly disperse, for which there are sometimes theoretical results available. For the interaction potential between hard spheres we quote references for the depletion interaction in the presence of polydisperse penetrable hard spheres [74], poly disperse ideal chains [75], poly-disperse hard spheres [76] and polydisperse thin rods [77]. 

Various polyesters such as poly (butylene terephthalate) have also been shown to be compatible with bisphenol A phenoxy resin. The suggested specific interaction here is between the hydroxyl of the phenoxy resin and the ester carbonyl. A wide range of polyesters have, however, also been found to be compatible with polycarbonates," where no hydroxyl groups are present. One might therefore consider that some interaction with the aromatic ring should be invoked of the sort that has been presumed to exist in the compatible pair, polystyrene-poly(vinyl methyl ether). A notable exception to the compatibility exhibited above is poly(pivalolactone) where the methyl groups might sterically hinder the interactions."... 

There has been some research using synthetic polymers, as well. Owen, et al. (90) employed optical tweezers and video microscopy. Here, poly(ethylene oxide), a water soluble polymer, was adsorbed onto 1.1 m diameter sihca microspheres in aqueous media, and the pair interaction potential was examined. This modeled the stabilization of colloidal matter by adsorbed polymer. Figure 14.25 (90) provides a schematic of the system. Four molecular weights of poly (ethylene oxide) were examined, ranging from 4.52 x 10 to 1.58 x 10 g/mol. 

PED Pedemonte, E. and Lanzavecchia, L., Pair interaction parameter for compatible polystyrene-poly(a-methylstyrene) mixtures, Thermochim. Acta, 162, 223, 1990. 

Figure 1 Examples of polymer pairs suited for layer-by-layer assembly (from top to bottom) by electrostatic interactions poly(styrene sulfonate)/poly(allylamin hydrochloride) by H-bonding polyaniline/poly(vinylpyrrolidone) (from Ref. 69) by H-bonding poly(4-vinyl pyiidine)/poly(acryhc acid) (from Ref. 71) by electron-donor-electron-ac-ceptor interaction poly(2-(9-carbazolyl)ethyl methacrylate)/poly(2-(3,5-dinitroben-zoyl)oxyethyl methacrylate) (from Ref. 75) by specific interaction biotinylated poly(lysine)/streptavidin (from Ref. 79).

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