In this paper, we investigate ultra-high-molecular-weight-polyethylene (UHMWPE) doped with conductive carbon black (CCB) nanoparticles. This nanocomposite is considered a candidate for biomedical applications such as orthopedics. Micro-computed tomography (μCT) and scanning electron microscopy studies show that the composite has a complex microstructure consisting of larger particles of UHMWPE surrounded by a thin layer containing a high concentration of CCB nano inclusions. The overall mechanical properties of these composites depend on the volume fraction of CCB and the manufacturing procedures e.g., compression molding or equal channel angular extrusion. To predict the effective elastic properties of the CCB/UHMWPE nanocomposite, we propose a multiscale modeling framework based on a combined analytical-numerical approach. μCT images are processed to extract the size, shape, and orientation distributions of UHMWPE particles as well as the volume fractions and spatial distribution of CCB containing layer. These distributions are used to develop multiscale numerical models of the composite including finite element analysis of representative volume elements on the mesoscale, and micromechanical predictions of CCB containing layer on the microscale. The predictive ability of the models is confirmed by comparison with the experimental measurements obtained by dynamic mechanical analysis.
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Investigation of Carbon Black/Ultra-High-Molecular-Weight-Polyethylene Nanocomposites Manufactured by Compression Molding and Equal Channel Angular Extrusion
Conductive carbon black (CCB) reinforced ultra-high molecular weight polyethylene (UHMWPE) polymers are investigated by micro-computed tomography, scanning electron microscope, and mechanical testing. The composites are manufactured by two techniques: compression molding (CM) and equal channel angular extrusion (ECAE). It is observed that electrical conductivity increases for the composites with the higher concentration of CCB inclusions without significant loss of tensile toughness. At the same time, ECAE procedure decreases the observed thickness of the CCB-rich layer and decreases electrical conductivity of the UHMWPE composites as compared to CM. Concentration of carbon inclusions in CCB-rich layer was evaluated for different weight fractions of CCB in the overall composite. Preliminary studies indicate that ECAE doesn’t change the orientation and elongation of UHMWPE particles in the CM consolidated composites.
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- Award ID(s):
- 1757371
- PAR ID:
- 10501169
- Publisher / Repository:
- Destech Publications, Inc.
- Date Published:
- ISBN:
- 9781605956916
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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