Acrylonitrile butadiene rubber (NBR, 35 % acrylonitrile contents) cure processing was carried out at different temperatures by rheometer. Surface and cut-surface functional groups were analyzed by X-ray photoelectron spectroscopy (XPS). Surface and cut-surface O element quantities of NBR cured at 140 °C were almost the same (2.1, 2.0 at.%), but much more than the O element content of uncured NBR (0.16 at.%). It means that there are some other chemistry reactions except the peroxide reacted with NBR rubber to get the cross-linking chain. And the oxide functional groups (>*CHOH and >C=O) were made from the O₂ which was left in the rubber. However, there are no -COOH on the surface and cut-surface of NBR cured at 140 °C. When the curing temperature is higher than 160 °C, the concentration of O on the surface of the NBR is increasing with the >*CHOH, >C=O and-COOH total functional oxide group number growing up, while the concentration of N1s has contrary trend with curing temperature increasing. It is considered that when the temperature is higher than 160 °C the cross-linking chain on the surface will be broken and the N was getting fewer. And the broken cross-linking chain can not be formed in the internal of NBR so that the concentration of O and N are almost the same as the cut-surface at the different temperature. Then the contact angle of the NBR surface is decreasing with the temperature increase for the increasing of oxide functional groups, while the ones of the cut-surface are same. Therefore, it is found that the surface and the interface of cured NBR after the cross-linking reaction by peroxide DCP have different chemical properties.

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Ozone resistance of poly(vinylidene fluoride-co-hexafluoropropylene-co-tetrafluoroethylene) (poly (VDF/HFP/TFE)) cross-linked by peroxide was examined in water. Although the poly(VDF/HFP/TFE)surface was not macroscopically damaged after the ozone treatment in water, physical properties at the surface were altered. Fourier-transform infrared spectroscopy with an attenuated total reflection mode (FT-IR ATR) revealed that the ozone treatment in water decreased the number density of the triallyl isocyanurate moiety, corresponding to the cross-linking point, of poly (VDF/HFP/TFE) elastomer in the vicinity of the surface. Finally, a correlation between the changes in primary structure and physical properties at the surface is discussed to give a better understanding of the ozone treatment to cross-linked poly (VDF/HFP/TFE) in water.

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It is well known that a part of cis-1,4 double bonds in diene rubbers is converted to trans-1,4 double bonds during the vulcanization, which is called cis-trans isomerization. In this article, effects of compounding ingredients on the cis-trans isomerization were studied by using electron spin resonance (ESR) and solid-state ¹³C-NMR results. The combination of ESR and NMR results revealed that the cis-trans isomerization was induced by a side reaction of the vulcanization by sulfur radicals. It was also found that the cis-trans isomerization was suppressed by zinc oxide. It is suggested that the reactivity of free sulfur radicals is enhanced by zinc oxide, resulting in the formation of C-S linkages on polymer chains.

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Solid polymer electrolytes (SPE) are proposed as solid state alternatives to liquid electrolytes in future electrochemical applications, such as lithium-ion batteries and dye-sensitized solar cells. The SPE however suffer from relatively low ionic conductivity in the solid state compared with most liquid, gel and ceramic electrolytes. Migration of ions in SPE can be realized by increasing local chain mobility of polyether, since ions are transported via the segmental motion. Unfortunately, cation-dipole interactions sometimes inhibit migration of ions because of their strong cohesion, that increases the glass transition temperature (T_g). Therefore, novel techniques that are not depend on the salvation and mobility of polyether are needed for the fast migration of ions. Here, two techniques (polymer blend and composite) are introduced as one of solutions for the SPE. In previous studies, simple polyether-, polyanion- and elastomer-based SPE blends have mainly been reported, but it was difficult to increase conductivity more than 10^–5 S cm^–1. On the other hand, addition of fillers to the SPE is another noteworthy technique, because this can give rise to the significant increase in conductivity, the inhibition of polymer re-crystallization, the decrease in T_g, and the increase in cation transport number. In this review, we prepared NBR/polyether electrolyte blends as novel electrostatic materials, synthesized hexagonally ordered mesoporous silica and used freeze-dried clay as novel inorganic fillers.

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This paper introduce recent progresses and future prospects of stretchable electronics, focusing on molecular electronic materials based thin film transistors for opening up new era of electronics. Especially, we review the fabrication of carbon-nanotube elastic conductors with excellent stretchability and conductivity. Furthermore, we present the fabrication of truly, rubber-like organic electronics with integrating elastic conductors as electrical inter connections and flexible organic transistors on stretchable rubbery substrates.

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