Synergetic effect of multi-walled carbon nanotubes (MWCNTs)/nanoclays hybrid was investigated on the properties of highimpact polystyrene (HIPS) nanocomposite foams. The glass transition temperature and the cellular structure including the cell size and cell density were studied in details. Adding MWCNT and nanoclay increased the glass transition temperature of HIPS by 8.5 °C and 1.5 °C, respectively. The experimental results indicated that the cell size of HIPS foams was reduced from 84.05 to 60.97 μm and 40.22 μm using MWCNTs and nanoclays, respectively. The synergetic effect of MWCNT/nanoclay was more significant by reducing the cell size to 13.69 μm. The cell density was improved from 5.79 × 104 to 1.77 × 105 cell/ cm3 using MWCNTs and to 9.39 × 106 cell/cm3 using nanoclays. The cell density reached to 2.90 × 107 cell/cm3 using the synergetic effect of MWCNT/nanoclay.

    Abstract
    1 Introduction
    2 Materials and methods
    3 Results and discussion
    4 Conclusions
    References

• Rezgar Hasanzadeh(Mechanical Engineering Department, Faculty of Engineering, Urmia University)
• Mohammad Mehdi Darvishi(Department of Engineering, Payame Noor University)
• Taher Azdast(Mechanical Engineering Department, Faculty of Engineering, Urmia University)