Atomic force microscopy (AFM) has an advantage of obtaining topographic and mechanical properties at the same time. In analyzing the force-distance curve using Hertz theory, Young's modulus is obtained with nanometer-scale resolution. Furthermore, sample deformation by the force exerted is also estimated from the force-distance curve analysis. We can reconstruct a real topographic image by incorporating apparent height with deformation image. We applied this method for obtaining information on mechanical properties of carbon black reinforced natural rubber. We were able to obtain Young's modulus distribution image together with apparent topographic and reconstructed real topographic images. Then we were able to recognize three regions; rubber, carbon black (or bound rubber) and interfacial regions. Though the existence of these regions had been investigated by pulsed nuclear magnetic resonance, this paper would be the first report on the quantitative evaluation of the interfacial region in real space.

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Styrene-butadiene rubber (SBR) was mixed with carbon black (CB), zinc oxide, etc. using 10L and 75L conventional kneaders equipped with conventional rotor, and 7L and 55L novel kneaders with new type rotor. The new type rotor used in this study has a large rotating shaft in comparison with the conventional type rotor. These rotors were installed in the same vessels, respectively. Under various rotating speeds and shear rates in the tip, Mooney viscosities and volume resistivities of SBR compounds were measured at arbitrary rotor revolutions. By using the new type rotor, it is thought that mixing will proceed not only in the tip region called the high shear region, but also in the annulus called the low shear region.
Mooney viscosities of compounds obtained by 55L kneader were lower than that by 75L kneader. Volume resistivities of compounds obtained by novel kneaders were higher than those by conventional kneaders.
At the initial stage of mixing in the novel kneader, it is supposed that most of CB was incorporated into SBR in the annulus to form the loose agglomerates of CB in rubber. This may be due to the low shear rate. Then the agglomerates will be collapsed to the fine aggregates of CB in rubber through subsequent mixing.

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Many Japanese rubber companies run rubber factories in Asia. Most of them buy rubber compounds from Asian transplants of Japanese rubber compounders. Elastomix (JSR group), Zeon and Saiko rubber has factories in Thailand, Malaysia and China. It seems that Japanese quality control of rubber mixing and recipe technology are superior to that of local compounders. Taiwanese rubber compounders start rubber custom mixing in China. Some European and American rubber custom mixing companies are doing their business in China, too. Japanese rubber factories in Thailand can use local rubber materials such as polymer and carbon black. Japanese rubber compounders in China are trying to use local carbon black and rubber chemicals. Most of major rubber compounders in Korea, Taiwan, Thailand, Malaysia, Indonesia, India and other Asia countries are described in this paper.

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The degradation behavior of EPDM by chlorine in water was reviewed. In the low concentration chlorine water such as city water, the degradation process was expected to be a lowering of EPDM molecular weight causing the softening. In the case of high chlorine concentration, on the other hand, reaction with chlorine increased the cross-linking density leading to hardening of EPDM. In addition, metal ion such as copper ion accelerates the chlorine degradation of EPDM.
The ozone concentration in the near ground atmosphere gradually increasing in recent 20 years because of the increasing nitrogen oxides exhausted from automobile and the strong short-wave UV light. We should consider measures against the ozone degradation of the rubber products at once.

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Some recent topics on EPDM are described from a viewpoint of globalization of Automotive manufacturer and environmental preservation. It will be required that EPDM have a good processability to obtain rubber products which have the same performance without any influence by place, machines and operators. And the social upsurge of environmental problems might change a curing system for EPDM.

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As a general introduction to anionic polymerization, this paper will review the categorization of anionic initiators and vinyl monomers according to Q-e values, the nature of carbanions in solution, especially their interaction with counter ions, the controlling of stereochemistry from 1, 3-diene and alkyl methacrylate polymerizations, and the basics of ring-opening polymerization. Vinyl monomers are categorized into four groups according to Q-e values. The anionic polymerizable monomers with higher Q values than 0.2 depend on their e values relating to the electron density on vinyl groups. The polymerization of high reactive monomers can be initiated with weak nucleophiles, while strong nucleophiles are required to initiate the polymerization of low reactive monomers. On the other hand, the relationship between reactivities of monomers and their active chain ends is basically inverse order. In order to understand the kinetics and mechanisms of anionic polymerization, the equilibriums among of the contact ion pair, the solvent separated ion pair, and free ion are discussed in terms of the reactivity of polystyryl anions. The dependence of stereochemistry of 1, 3-diene monomer and alkyl methacrylate polymerizations on the counter cation, solvent, and additive is described.

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