Kinetics polymer thermodynamics

At present, intercalation compounds are used widely in various electrochemical devices (batteries, fuel cells, electrochromic devices, etc.). At the same time, many fundamental problems in this field do not yet have an explanation (e.g., the influence of ion solvation, the influence of defects in the host structure and/or in the host stoichiometry on the kinetic and thermodynamic properties of intercalation compounds). Optimization of the host stoichiometry of high-voltage intercalation compounds into oxide host materials is of prime importance for their practical application. Intercalation processes into organic polymer host materials are discussed in Chapter 26. 

Optical methods are a perfect tool to characterize interaction processes between a sensitive chemical or bio polymer layer and analytes1. Time-resolved measurements of this interaction process provide kinetic and thermodynamic data. These types of sensors allow the monitoring of production processes, quantification of analytes in mixtures and many applications in the area of diagnostics, biomolecular interaction processes, DNAhybridization studies and evenprotein/protein interactions2,3. 

Finally, the theory for the bioenergetics and kinetics of microtubule assembly and disassembly of microtubules has been extended by Hill and Kirschner (1983). They consider the coupling of nucleotide hydrolysis in terms of the energetics of the [GTP]/[GDP][PJ mass action ratio, the possible effects of force imparted by attachment of tubules to barriers on the rate constants, and other intriguing aspects of protomer-polymer exchange kinetics and thermodynamics. Unfortunately, much of their theory remains to be tested, and an evaluation of its importance in revealing the subtleties of assembly/disassembly remains for future investigations. 

Both kinetic and thermodynamic approaches have been used to measure and explain the abrupt change in properties as a polymer changes from a glassy to a leathery state. These involve the coefficient of expansion, the compressibility, the index of refraction, and the specific heat values. In the thermodynamic approach used by Gibbs and DiMarzio, the process is considered to be related to conformational entropy changes with temperature and is related to a second-order transition. There is also an abrupt change from the solid crystalline to the liquid state at the first-order transition or melting point Tm. 

C nmr has been used to follow the polymerization of 1,3 butadiene with either n-BuLi or t-BuLi. The disappearance of unreacted monomer and the growth of the initial polymer peaks are readily followed. Kinetic and thermodynamic data can be obtained. 

Kabanov et al.116 studied the oxidation of ascorbic acid by the Cu(II) complexes of poly(4-vinylpyridine) partially alkylated by bromoacetic acid. It was considered from kinetic and thermodynamic data that the higher catalytic activity of the polymer-Cu complex was caused by binding of the substrate to the catalytic site, represented as 48. 

Micro-encapsulation, as obtained by continuous SAS techniques, is a physical process, guided both from thermodynamics and kinetics. The entire process involved is not clear. Mass-transfer kinetics and thermodynamic equilibria related to polymer-particle precipitation from a solution expanded by supercritical CO2 are currently being investigated [9,10], Many empirical observations are now available, suggesting that for a given polymeric solution, both pressure and temperature play an important role in determining the precipitated particles morphology. 

Polymer catalysts showing interactions with the substrate, similar to enzymes, were prepared and their catalytic activities on hydrolysis of polysaccharides were investigated. Kinetical analyses showed that hydrogen bonding and electrostatic interactions played important roles for enhancement of the reactions and that the hydrolysis rates of polysaccharides followed the Michaelis-Menten type kinetics, whereas the hydrolysis of low-molecular-weight analogs proceeded according to second-order kinetics. From thermodynamic analyses, the process of the complex formation in the reaction was characterized by remarkable decreases in enthalpy and entropy. The maximum rate enhancement obtained in the present experiment was fivefold on the basis of the reaction in the presence of sulfuric acid. 

Most of the systems described in Chapter 5 contain small- or medium-sized or multinuclear benzenoid and non-benzenoid arenes. In Chapter 6, Hoger gives an overview over the mastery of the synthesis of macro- and megacycles. He shows different approaches towards shape-persistent macrocycles and carefully examines and discusses selected examples that display the advantages and disadvantages of macrocycle synthesis under kinetic and thermodynamic control. The template approach (both supramolecular and covalent) towards functionalized rings is also discussed and introduces a strong motif of supramolecular chemistry, which is much further developed but in a more polymer-oriented topic, in the next chapter. 

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