Microcellular foaming of PP/EPDM/organoclay nanocomposites: the effect of the distribution of nanoclay on foam morphology

作者：Keramati Mohsen; Ghasemi Ismail^*; Karrabi Mohammad; Azizi Hamed

来源：Polymer Journal, 2012, 44(5): 433-438.

DOI：10.1038/pj.2012.2

• microcellular foam
• nanoclay distribution
• nucleation
• PP/EPDM

In this study, microcellular foams based on polypropylene/ethylene propylene diene monomer/organoclay (PP/EPDM/organoclay) nanocomposites were produced via a batch process using supercritical nitrogen (N-2) as the physical blowing agent. The foaming temperature and morphological observation demonstrated that foaming occurred mostly in the PP phase. To evaluate the effect of organoclay distribution on the cell nucleation step and the final foam morphology, the location of the nanofillers in the nanocomposite blend was traced by means of surface energies and Young's equation. The calculated wetting coefficient predicted that the organoclays would have more affinity with PP and would primarily distribute into the PP phase. These results were confirmed by atomic force microscopy (AFM), dynamic mechanical thermal analysis (DMTA) and transmission electron microscopy (TEM). The cell density and average cell sizes are the main foam characteristics that were determined using SEM micrographs, and it was found that these parameters were influenced by the presence of nanoclays. An improved foam morphology was obtained in the nanocomposite samples. Polymer Journal (2012) 44, 433-438; doi:10.1038/pj.2012.2; published online 15 February 2012

• 出版日期2012-5