Authors: M. Abdel-Goad, B. Kretzschmar, P. Pötschke, R. Al-maameri, G. Heinrich
Affilation: Sultan Qaboos University, Oman
Pages: 973 - 976
Keywords: PP/Clay nanocomposities, exfoliation, rheology
Polypropylene/clay nanocomposites were prepared by using a two step melt compounding process on twin screw extruders. In order to enhance the exfoliation, time and degree of mixing were varied using different screw speeds and dosing positions of the clay in the step of compounding a PP-g-MA/clay masterbatch. Moreover, in some cases a a reactive modifier was added to the chemical reaction of the compatibilizer. In addition to, samples were taken from different positions along the processing unit. The PP-clay nanocomposites were rheologically investigated. The melt rheological measurements were performed using an ARES-rheometer (Rheometrics Scientific, USA) in the dynamic mode at 220°C over frequency varying from 100 to 0.017 rad/s and in the parallel plate geometry with 25 mm diameter. The dynamic mechanical properties and complex viscosity have been studied . The results showed that the dynamic mechanical moduli and viscosity are found to be increased with the incorporation of clay into PP and their values tend to slightly change as the preparation conditions, compatibilizer type and the reactive modifier change. The results also give an evidence of the exfoliation. The degree of exfoliation was increased up to a certain limit with increasing the annealing time at 220°C.