Nanoindentation and dynamic mechanical properties of PP/clay nanocomposites

Abstract

Polypropylene/clay nanocomposites were prepared by melt blending technique. A PP homopolymer was melt blended with commercial nanoclay masterbatch at different concentration (5, 10 and 15 wt% of nanoclay) using Laboratory Mixing Extruder (LME). The morphology of the nanocomposites was characterized using Scanning Electron Microscope (SEM). The viscoelastic and thermomechanical properties were analyzed via Dynamic Mechanical Analysis (DMA). The morphological analysis showed that the nanoclay was well distributed in the PP matrix. The DMA analysis showed an increase in storage modulus of nanocomposites which indicates an enhancement of stiffness and thermal stability of the prepared nanocomposite samples. In addition, a nanoindentation test was performed to determine the dynamic nanomechanical properties of two nanocomposites samples (NS-5 and NS-15). Load sweep test results showed that NS-15 has a slightly higher storage and loss modulus than that of NS-5. Both the samples also showed a decreasing modulus as a function of depth, indicating the presence of a stiffer surface layer in the samples. Frequency sweep tests were also performed on each sample, and display a moderate viscoelasticity with modulus values that increased slightly as a function of frequency. Loadcontrolled ramping force scratch test was also carried out and the results showed that NS-15 had a greater elastic recovery than sample NS-5 as well as a greater overall scratch resistance.

Mechanical properties of electrochemically synthesised metal–organic framework thin films

“…So, even though the scratch depth in the ploughing mode for Cu(CHDA) is more than 1300 nm (elastic deformation), the residual prole is only 400 nm deep (plastic deformation). The elastic recovery of Cu(CHDA) is comparable with that of organic polymers and nanocomposites (60-80%), 44,45 while Cu(INA) 2 has a similar value as a scratched zeolite MFI lm (37%). 46 In order to further analyse the possible loss of mechanical integrity of the MOF lms, scratches were evaluated by SEM.…”

Enhanced dispersion of carbon nanotubes in high density polyethylene matrix using secondary nanofiller and compatibilizer

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Crystallization, melting, and mechanical behavior of calcium carbonate‐based nanocomposites of crosslinked high density polyethylene

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