Fullerenes are typical nano-carbon materials with interesting properties.To demonstrate theirability to improve the properties of thermoplastic resins, synthetic thermoplastic polyurethane elastomer (PUE) was used as a matrix, and it was compounded with various fullerenes.Various physical properties of the resulting composite materials were then measured, and the relationship between physical properties and phase structure was examined.The fullerenes used were C60, mixed fullerenes (a mixture of C60, C70, and higher fullerenes; MF) and the solvent-insoluble carbon (FB) similar to fullerenes that is produced during fullerene manufacturing.In terms of tensile properties of the composites obtained using the solvent method, tensile moduli were improved through addition of fullerenes at a level of just several hundred ppm, and the onset of modulus improvement occurred at an early stage.Moreover, it was also proven that composites obtained using a compounding method whereby the fullerene powder was blended into the PUE using a tworoll-mill possessed properties that were very similar to composites obtained using the solvent method.Similarly, mechanical properties were improved by the addition of FB.The functional mechanism of the fullerenes was ascertained from differential scanning calorimetry and a dynamicmechanical analyzer.It is anticipated that such trace amounts of addition will prove a useful industrial technique since processability and formability are hardly affected.

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Effects of phenoxy and CPP contents on morphologies and properties of cured epoxy/phenoxyblends and cured epoxy / phenoxy / CPP blends for halogen-free adhesives on FPCs were studied.Peel strength and elongation of the cured epoxy /phenoxy blends showed maximum values at a 30wt% of phenoxy contents without reducing Tg and reliability of electric resistance which is a big problem oncured epoxy / NBR blends.Since morphologies of cured epoxy rich phases and phenoxy rich phasesshowed co-continuous structures, above maximization of peel strength and elongation would be attribute to a good balance between high cohesive power of cured epoxy phases and high toughness of phenoxy phases. Furthermore, CPP blends achieved halogen-free flame retardancy (VTM-0) on cured epoxy /phenoxy /CPP blends when a CPP content was slightly 3wt% (phosphorus content was 0.4wt%) and CPP did not show bad effects on properties of the cured blends.

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