Abstract
Small-angle X-ray scattering (SAXS) monitors tensile
and load-cycling tests of metallocene isotactic polypropylene (PP), a
blend of PP and montmorillonite (MMT), and two block copolymer
compatibilized PP/MMT nanocomposites. Mechanical properties of the
materials are similar, but the semicrystalline nanostructure of the PP
differs. This is explained by a nucleation effect of the MMT. Competitive
crystal growth diminishes crystallite sizes. The reinforcing effect of
the MMT filler appears consumed by weakening the PP matrix. Decays
of mechanical and nanostructure response in dynamic load cycling
indicate materials fatigue. Lifetimes describe the reinforcing and weakening effects. Addition of 3% MMT halves the fortifying
effect of the PP nanostructure. A net gain of reinforcement (11%) is observed with the highly compatibilized composite in which
the strength of the semicrystalline PP is reduced to 25%. Other results concern the evolution of Strobl’s block structure and void
formation during tensile loading.
and load-cycling tests of metallocene isotactic polypropylene (PP), a
blend of PP and montmorillonite (MMT), and two block copolymer
compatibilized PP/MMT nanocomposites. Mechanical properties of the
materials are similar, but the semicrystalline nanostructure of the PP
differs. This is explained by a nucleation effect of the MMT. Competitive
crystal growth diminishes crystallite sizes. The reinforcing effect of
the MMT filler appears consumed by weakening the PP matrix. Decays
of mechanical and nanostructure response in dynamic load cycling
indicate materials fatigue. Lifetimes describe the reinforcing and weakening effects. Addition of 3% MMT halves the fortifying
effect of the PP nanostructure. A net gain of reinforcement (11%) is observed with the highly compatibilized composite in which
the strength of the semicrystalline PP is reduced to 25%. Other results concern the evolution of Strobl’s block structure and void
formation during tensile loading.
| Original language | English |
|---|---|
| Journal | Macromolecules |
| Volume | 45 |
| Issue number | 2 |
| Pages (from-to) | 962-973 |
| ISSN | 0024-9297 |
| DOIs | |
| Publication status | Published - 2012 |