Investigation of various factors effects on mechanical properties of Poly(propylene)/organo-modified Montmorillonite/ Magnesium hydroxide composites

The combined effects of organo-modified montmorillonite (O-MMT) gallery polarity, surface modification of magnesium hydroxide (MDH), maleic anhydride grafted polypropylene (MA-g-PP) and antioxidant (Irganox 1010) addition, together with mixing time and rotor speed of the mixer on the measured flexural modulus, maximum (max) flexural (flex) strength and impact strength of the composites were studied. A two-level factorial experimental design of these variables was used to examine their simultaneous effects. The 16 composite samples were prepared by melt mixing in an internal mixer at 200 degrees C and their properties were measured. The flexural modulus and max flex strength of the samples containing high level of both MDH and O-MMT reached the highest and lowest amount respectively. Effect of the factors and their interactions on impact strength and max flex strength was almost in the same order and by decreasing the amount of O-MMT/or MDH, these properties were increased. The regression equations showed the most effective factors and their interactions which were in good agreement with the obtained results. Addition of 1% w/w O-MMT to 50% w/w MDH/PP composites led to the best mechanical properties.