Effects of contents of a phenoxy resin containing phosphorus on morphologies and properties of cured BPA epoxy resin/phenoxy resin containing phosphorus blends and cured epoxy resin/BPA phenoxy resin blends for halogen-free adhesives to produce Flexible Printed Circuits(FPCs) were studied.Phases of the phenoxy resin containing phosphorus were miscible with cured BPA epoxy resin matrices.The halogen-free flame retardancy(VTM-O) was achieved at the phenoxy resin containing phosphorus contents of over 20 wt.% which corresponds to phosphorus contents of over 0.9 wt.%.The tensile elongation and the peel strength was increased slightly at the phenoxy resin contents of over 40 wt.% respectively.The insulation reliability was not decreased at all even if contents of the phenoxy resin containing phosphorus were increased.Contrastively,cured epoxy resin/BPA phenoxy resin blends formed microstructures where phases of BPA phenoxy resin were separated with cured BPA epoxy resin matrices.The tensile elongation and the peel strength plotted against the contents of the BPA phenoxy resin showed curves having maximum points at the phenoxy resin contents of 30～50 wt.% where co-continuous microstructures were formed.The reliability of electric insulation was decreased at a range of BPA phenoxy resin contents of 30～50wt.%.

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The effects of interfacial adhesion between multi-walled carbon nanotubes(MWCNTs) and terminalfunctionalized polystyrene-blockｰpoly(ethylene-co-butylene)-block-polystyrene（SEBS）matrices have been investigated by determining the mechanical properties of these composites.SEBS with no functionalization(SEBS-1) and SEBSs functionalized by carboxylic acid group(SEBS-3),amino group (SEBS-4), and maleic acid anhydride groups on the middle block (SEBS-2) were used.The nanocomposites were prepared by using a roll mill.The tensile properties and electric conductivity of all the composites improved with increasing MWCNT content.In the SEBS-4 composite system,the tensile moduli were almost three times higher than those of pure SEBS-4 with 17.8vol% of MWCNT.Further,the electricpercolation threshold of CNT/SEBS-4 was higher than that of the others;this indicates that the terminal amino group significantly contributes to the interfacial adhesion,even when the content of the terminals is relatively low.In mechanical analysis of the composites,a broad loss tangent peak appeared at the temperature region between the glass transition point of the midblock and the polystyrene block.These results suggest that a stereoscopic network structure is formed by the loading of MWCNTs.

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