In this study, multiwalled carbon nanotube (MWCNT) and ethylene vinyl acetate copolymer (EVA) nanocomposite bulk foams were prepared for static dissipative applications by using melt compounding method, the most compatible with current industrial applications. Closedcell structure was verified with Scanning Electron Microscope. All the mechanical properties investigated improved with increasing content of MWCNT except elongation at break. At 5 phr of MWCNT, significant improvement of mechanical properties and compression set were observed. Also, the surface resistivity begins to decrease at 5 phr of MWCNT. Interestingly, the increase of surface resistivity of nanocomposite foams with 8 and 10 phr MWCNT were observed with increasing thickness of removed surface layers.

To chemically bond polymer and organoclay, low molecular weight trimethoxysilyl-modified polybutadiene (Silane) was used in this study. When Silane was added, ethylene-vinyl acetate copolymer (EVA)/ethylene-1-butene copolymer (EtBC)/methyl tallow bis-2-hydroxyethyl quaternary ammonium-modified montmorillonite (OH-MMT)/Silane foams with and without maleic anhydride grafted EtBC (EtBC-g-MAH) display lower compression set than EVA/EtBC foams. According to the compression set result, OH-MMT is more effective in improvement of compression set than dimethyl dihydrogenated tallow quaternary ammonium-modified montmorillonite (DM-MMT) because in addition of OH groups in the organoclay surface, the OH groups of the alkylammonium ion existed in interlayer of OH-MMT may react with silanol group of Silane. The possible chemical reactions between Silanol groups of Silane and the hydroxyl groups of OH-MMT and DM-MMT were proved by ATR-FTIR experiments.

In this study an attempt was made to obtain lower density of ethylene-vinyl acetate copolymer (EVA)/ ethylene-1-butene copolymer (EtBC) foams without sacrificing mechanical properties. For this purpose EVA/EtBC/clay nanocomposite foams were prepared. To investigate the effect of compatibilizer and silane coupling agent on the physical properties of the EVA/EtBC/clay foams, maleic anhydride-grafted EtBC (EtBC-g-MAH) and the most commonly used silane coupling agent in rubbers, bis(3-triethoxysilylpropyl) tetrasulfide (Si-69) were used in the preparation of EVA/EtBC/clay nanocomposite foams. The formation of EVA/EtBC/clay nanocomposite foams was supported by X-ray diffraction results. And, using a compatibilzer and silane coupling agent, lower density of EVA/EtBC/clay nanocomposite foams were obtained without sacrificing mechanical properties except compression set.

In this study, our goal is to obtain lower density of ethylene-vinyl acetate copolymer (EVA)/ethylene-1-butene copolymer (EtBC) foams without sacrificing mechanical properties. For this purpose EVA/EtBC/organoclay (Cloisite 15A, Closite 30B) nanocomposite foams were prepared. To investigate the effect of compatibilizer on the dispersion state of organoclay in cellular foam structure and mechanical properties of the EVA/EtBC/ organoclay foams composites were prepared with and without maleic anhydride grafted EtBC (EtBC-g-MAH). The dispersion of organoclay in EVA/EtBC/organocaly foams was investigated by X-ray diffraction and transmission electron microscopy. The EVA/EtBC nanocomposite foams with the compatibilzer, especially EVA/EtBC/Cloisite 15A/EtBC-g-MAH foams displayed more uniform dispersion of organoclay than EVA/EtBC nanocomposite foams without the compatibilzer. As a result, EVA/EtBC/ Cloisite 15A/EtBC-g-MAH foams have the smallest average cell size and highest 100% tensile modulus followed by EVA/EtBC/Cloisite 30B/EtBC-g-MAH foams.

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