Nonisothermal crystallization kinetics of polypropylene-layered double hydroxide composites: Correlation with morphology

✍ Scribed by Maurizio Penco; Gloria Spagnoli; Md. Arifur Rahman; Elisa Passaglia; Serena Coiai; Francesco Ciardelli

• Book ID: 104510764
• Publisher: Society for Plastic Engineers
• Year: 2011
• Tongue: English
• Weight: 496 KB
• Volume: 32
• Category: Article
• ISSN: 0272-8397
• DOI: 10.1002/pc.21097

✦ Synopsis

Abstract

In this work the effect of nanofiller on nonisothermal crystallization behavior of composites based on polypropylene (PP) was investigated by differential scanning calorimetry. The materials were prepared by melt mixing. Both an alkyl sulfonate salt modified layered double hydroxide (LDH) and an unmodified LDH were used as nanofillers and both PP and PP/polypropylene grafted with maleic anhydride (PP‐g‐MA) blend were used as matrices. The morphology of composites was investigated by X‐ray diffraction and transmission electron microscopy. No exfoliation was noticed in all prepared composites, but the hybrid materials showed an intercalated structure. The thermal properties and crystallization behavior were studied by conventional differential scanning calorimetry. In particular, the kinetic crystallization parameters were obtained using the modified Avrami equation for a nonisothermal process, whereas the activation energy of the global crystallization process was estimated using the Kissinger equation. The Avrami parameters suggest a significant effect on the crystallization of PP for the composites containing both the organically modified LDH and PP‐g‐MA. The results indicate a complex crystallization process of PP and evidence that the crystallization process can not be only explained by intercalation phenomenon, but the constrain effect ofpolymer chains on the filler surface and/or betweenthe filler clusters should play a significant role. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers