Structure property and deformation analysis of polypropylene montmorillonite nanocomposites.

Nanocomposites with expandable smectites such as montmorillonite layered silicates (MLS) in polymer matrices have attracted extensive application interest. Numerous MLS concentrations have been used with no particular justification. Here, we investigate the effects of MLS dispersion within the matrix and on mechanical performance. The latter is resolved through a three-prong investigation on rate dependent tensile results, time dependent creep results and the influence of a sharp notch in polypropylene (PP) nanocomposites. A fixed concentration of maleated polypropylene (mPP) was utilized as a compatibilizer between the MLS and non-polar PP. Analysis of transmission electron micrographs and X-ray diffraction patterns on the surface and below the surface of our samples revealed a unique skin-core effect induced by the presence of clay. Differential scanning calorimetric and polarized optical microscopic examination of spherulites sizes showed changes in nucleation and growth resulting from both the maleated PP compatibilizer and the MLS. These structural changes resulted in a tough nanocomposite, a concept not reported before in the PP literature. Nonlinear creep analysis of the materials showed two concentrations 3 and 5 % wt of PP, which reduced the compliance in the base PP. The use of thermal wave imaging allowed the identification of ductile failure among materials, but more important, aided the mapping of the elastic and plastic contributions. These are essential concepts in fracture analysis.

Grantor dc:publisher

University of North Texas

Year dc:date

2003

Author dc:creator

• Hernandez-Luna, Alejandro

Contributors dc:contributor

• D'Souza, Nandika A.
• Drewniak, Marta
• Gnade, Bruce
• Hu, Zhibing
• Reidy, Richard

• Nanostructured materials.
• Polymeric composites.
• Montmorillonite.
• Polypropylene.
• nanocomposites
• skin-core effects
• thermal wave
• imaging
• mechanical property

Statement dc:rights

• Public
• Copyright
• Hernandez-Luna, Alejandro
• Copyright is held by the author, unless otherwise noted. All rights reserved.

Language dc:language

English

Identifier

oclc: 53185467
https://digital.library.unt.edu/ark:/67531/metadc4213/
ark: ark:/67531/metadc4213

OAI identifier oai:identifier

info:ark/67531/metadc4213