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Due to its high strength and low weight properties, structural components made from carbon fiber reinforced composites (CFRCs) are increasingly being utilized in the automotive, aerospace, and wind power industries. A common matrix material for these composites is epoxy resin, which it is very brittle in nature and limits applications of these CFRCs. Introducing rubber fillers is known to increase the toughness of epoxy resin, but is at the expanse of strength and modulus. However, nanosilica particles have been known to increase mechanical properties when added to epoxy resin. Therefore, this research focuses on the effects of introducing both core-shell rubber elastomer nanoparticles and nanosilica particles into the matrix to form a hybrid carbon fiber reinforced epoxy nanocomposite. The nanoparticles were dispersed into the epoxy resin through high shear mixing and the composites were manufacturing using the Vacuum Assisted Resin Transfer Molding (VARTM) process. Analyzing the dispersion and structure of the resulting nanocomposites was done using a scanning electron microscope (SEM). Furthermore, the static mechanical and fatigue properties were characterized. In characterizing the fatigue, a S-N curve and stiffness degradation model was developed. The hybrid showed increases in tension, flexural, and inter-laminar shear strength compared to the control composite. The hybrid also showed significant enhancements in fatigue life and stiffness degradation when compared to the control composite, as well as composites containing only the core-shell or silica nanoparticles. This research could further support future work related to the expansion of carbon fiber reinforced nanocomposites structural application in the automotive, aerospace, and wind power industries. [ABSTRACT FROM AUTHOR]

Nanocomposite materials are multiphase solid materials in which one of the phases has one, two or three dimensions of less than 100 nanometers (nm). "Nanocomposites" can also be used to describe a polymer matrix into which nanoparticles have been added to improve a property of the material. Nanocomposite materials play a vital role in a wide range of applications in aerospace, automotive, sports, and biomedical industry. Their adaptability to different situations and desirable properties has made them attractive to many industries. While thermoplastic nanocomposites exhibit excellent mechanical, electrical, and thermal properties of the material in Additive Manufacturing, they occasionally fail to maintain their mechanical properties. The prime objective of this study is to produce and characterize polyamide 6/Nanographene platelets nanocomposites. These materials have improved electrical conductivity for electrostatic charge dissipation applications with minimal reduction in mechanical properties. Polyamide 6 and Nanographene platelets were first melt blended using an industry size, co-rotating twin-screw extruder. Tension and electrical resistivity test samples for neat PA6, PA6/NGP with different loading such as 3wt.%, 5wt.% and 7wt.% were prepared using fused deposition modeling on a Lulzbot TAZ 6 3D printer. Electrical resistivity was measured using a Hioki Megohmmeter instrument. Mechanical characterization includes tensile test of the samples. The recommended range of electrical resistivity of a nanocomposite material system for ESD applications is in the range of 1010 - 1011 Ω-cm. [ABSTRACT FROM AUTHOR]

This paper explores the changes in mechanical properties when thermoplastic polyurethane (TPU) is mixed with nanosilica (NS) made from rice husk. Twin-screw extrusion and a ram injection molding system were used to produce tensile specimens per ASTM D412. A control, as well as 1 weight percent (wt%) and 3 wt% formulations were produced. Tensile testing, dynamic mechanical analysis (DMA), thermomechanical analysis (TMA), and thermogravimetric analysis (TGA) were performed on the specimens. A detailed analysis of the data was then made to establish relationships found between increasing NS content and tensile strength, tensile modulus, percentage elongation, thermal stability, and viscoelastic properties. It is observed that material residence time in the twin screw extruder has a major effect on dispersion quality and in turn mechanical and thermal properties. [ABSTRACT FROM AUTHOR]

The specific objective of this research is to produce and characterize polyamide 11/ nanographene platelets nanocomposites that have improved electrical conductivity for electrostatic charge dissipation applications. Polyamide 11 and nanographene platelets were blended using industry size co-rotating twin-screw extrusion. Tension and electrical resistivity test samples for neat PA11, 3 wt.% PA11/NGP and four different types of metal filled PLA were prepared using fused deposition modeling on Lulzbot Taz 4 3D printer. Electrical resistivity was measured using the Hioki Megaohmmeter Instrument. Mechanical characterization includes tensile test of the samples. The only material system that was qualified for electrostatic charge dissipation (ESD) applications was conductive graphite PLA. The recommended range of electrical resistivity for ESD applications is in the range of 1010 - 1011 Ω-cm. [ABSTRACT FROM AUTHOR]