Epoxidized Natural Rubber-Alumina Nanoparticle Composites: Optimization of Mixer Parameters via Response Surface Methodology

Epoxidized natural rubber-alumina nanopar- ticle composites were prepared by melt compounding with an internal mixer for a constant filler loading of 10 phr. Mixer parameters such as the mixing temperature, mixing time, and rotor speed were screened and optimized with response sur- face methodology to maximize the impact strength. The pa- rameters were selected as three independent variables and the impact strength (J/m) was selected as the response in a screening factor study. The mixing temperature and its inter- action terms were identified as insignificant factors with a P value greater than 0.0500. The optimum calculated values of the tested variables (rotor speed and mixing time) for the maximum impact strength were found to be a rotor speed of 60 rpm and a mixing time of 6 min with a predicted impact strength of 208.88 J/m. These predicted optimum parameters were tested in real experiments. The final impact strength was found to be close to the predicted value of 215.84 J/m, with only a 3.33% deviation. V C 2009 Wiley Periodicals, Inc. J Appl Polym Sci 115: 183-189, 2010