Ion Binding to Poly(oxyethylene) in Methanol latter for the p-nitroperbenzoic acid results could be appreciable. Effect of Brownian Motion of the LigandWhen the target area is smaller than the mean free path of the ligand, the diffusion-controlled rate constant cannot be deduced from a simple diffusion equation.36 However, the mean free path, L, calculated from the following equation36 is only 0.07 Á for p-nitroperbenzoic acid, where M is molecular weight and R is gas constant: L D( §iY Therefore, the effect of Brownian motion is almost negligible for the horseradish peroxidase-ligand system. Publication costs assisted by Tohoku UniversityThe binding of alkali metal cation with poly(oxyethylene) was studied by means of conductometry in methanol. Apparent binding constants, KA, were determined by assuming the existence of discrete binding sites distributed every a monomer units along the polymer chain. KA increased in the order Li < Na < K < Cs < Rb. For large anions, such as thiocyanate or perchlorate, the formation of an ion pair complex was indicated. KA and a increased rapidly with decreasing salt concentration. This result was interpreted by the increased electrostatic repulsion between bound ions. The linear relationship between a1/2 and Cs"1/2 conforms to the Gaussian distribution of the segment between charges as well as to the partial retention of crystalline conformation of the poly-(oxyethylene)-ion complex.Publication costs assisted by the National Science Foundation and the Petroleum Research Fund Two recent theories for ionic mobility, the Hubbard-Onsager theory which is based on a continuum model and the Wolynes theory which is based on a stochastic model, are critically tested by comparison with conductance data. Both theories predict finite mobilities as the ionic size decreases and thus can successfully account for many of the observed features of conductance data. The models upon which the theories are based are described in detail and the current state of ionic mobility theory is discussed.

Measurements of relaxation of stress were carried out in the region of rubbery flow on two samples of polystyrene, A and B. Sample A was prepared by the Szwarc technique which is designed to produce monodisperse polymer. Sample B was prepared by radical-initiated polymerization of styrene carried to low conversions. It was shown by Baysal and Tobolsky2 that the molecular weight distribution under these conditions is given by X ( n ) = np"-'(l -P )~, where X ( n ) is the mole fraction of polymer whose degree of polymerization is n. For this distribution the ratio of

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SynopsisThe isothermal degradation of high cis-l,4-polyisoprene Vulcanizates having different crosslinking structures was investigated by a measurement of weight loss of sample, I R and NMR, gel permeation chromatography (GPC), and gas chromatography (GC). The degradation behavior of dicumy peroxide-cured sample is similar to that of the uncrosslinked one. On the other hand, a sulfur-cured sample is very different from the other samples. At the initial stage of the degradation, weight loss in this sample is faster than that in an uncrosslinked one. Furthermore, a microstructural change in this polymer occurring by thermal degradation is also very much larger than microstructural changes in the others. This will be attributed to polythiyl radicals produced by the scission of polysulfide crosslinkages. Although the polyisoprene chain undergoes random scission along the main chain above 473 K under inert gas or in uacuo, a molecular weight distribution of the residue after thermal degradation was broadened as the degradation proceeded. That is to say, the fragments having enormous molecular weight increase together with the production of lower molecular weight compounds. This indicates the occurrence of crosslinking reaction and the addition of polymer radicals to carbon-carbon double bonds in another polymer molecule in the thermal degradation process. Such reactions are thought to take place in the crosslinked polymers, in particular the sulfur-cured polymer, in larger quantities. Thermal degradation mechanisms were discussed in some detail.

Organic gases cause carbon depositions on the multi-layer mirrors by Extreme Ultra Violet (EUV) light irradiations in EUV lithography tool. The dependences on organic gas species, organic gas pressure and EUV light intensity in the carbon deposition were researched in order to understand this reaction. EUV light was irradiated on a (Si/Mo) multilayer mirror sample injecting organic gas like buthane, buthanol, methyl propionate, hexane, perfluoro octane, decane, decanol, methyl nonanoate, diethyl benzene, dimethyl phthalate and hexadecane. X-ray photoelectron spectroscopy measurements revealed that organic gases with heavier molecule weight or higher boiling temperature caused faster carbon deposition rates. Carbon deposition rates increased linearly with organic gas pressures. Dependence on EUV light intensity was estimated from comparisons between an EUV light profile and carbon distributions on irradiated samples. Carbon deposition rates increased rapidly, but became saturated at higher EUV light intensities. Three chemical reactions, an adsorption, a desorption and a carbon deposition by EUV light irradiation, were taken into account to explain the behavior of the carbon deposition. Electron irradiation on a mirror sample revealed that photoelectrons emitting from the mirror surface played an important role in carbon deposition.

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