Molecular dynamics study of specific interactions in grafted polypropylene organomodified clay nanocomposite

A molecular dynamics study was performed to analyze the interaction energy between an organomodified clay surface and functionalized polypropylene. A supercell containing montmorillonite with a cation exchange capacity of 140 meq/100 g organomodified with octadecyldimethyl 2-ethylhexyl ammonium and four polymer chains of 25 repeating units length was constructed. According to our results, pure polypropylene shows favorable interactions with organomodified clay surface. Theses interactions are improved in the presence of certain functional groups. The best improvement is obtained with maleic anhydride. Such result is actually in agreement with experimental data.