The Effect of Hybridized Carbon Nanotubes, Silica Nanoparticles, and Core-Shell Rubber on Tensile, Fracture Mechanics and Electrical Properties of Epoxy Nanocomposites.

Ankur Bajpai,Stéphane Carlotti

doi:10.3390/nano9071057

Abstract

The paper investigates the effect of adding a combination of rigid nanoparticles and core-shell rubber nanoparticles on the tensile, fracture mechanics, electrical and thermo-mechanical properties of epoxy resins. SiO2 nanoparticles, multi-walled carbon nanotubes (MWCNT’s), as rigid nanofillers, and core-shell rubber (CSR) nanoparticles, as soft nanofillers were used with bisphenol-A-based epoxy resin. Further, the rigid fillers were added systematically with core-shell rubber nanoparticles to investigate the commingled effect of rigid nanofillers and soft CSR nanoparticles. The resulting matrix will be broadly evaluated by standard methods to quantify tensile, fracture mechanics, electrical, and thermal properties. The results show that the electrical conductivity threshold is obtained at 0.075 wt. % for MWCNT-modified systems. For hybrid systems, the maximum increase of fracture toughness (218%) and fracture energy (900%) was obtained for a system containing 5 wt. % of CSR and 10 wt. % of SiO2. The analysis of the fracture surfaces revealed the information about existing toughening micro-mechanisms in the nanocomposites.

Highlights

Epoxy resins belong to a class of highly cross-linked thermoset polymers used most often with reinforcing fibers in a wide range of composite applications, e.g., automotive, aerospace, and pressure vessels [1]
The fracture energy can be increased by adding different modifiers to the epoxy resin, e.g., carboxyl-terminated butadiene acrylonitrile (CTBN) [2,3]
The objective of this study is to show the effect of SiO2, multi-walled carbon nanotubes (MWCNT’s) and core shell rubber (CSR) nanoparticles loading on the mechanical, electrical, and thermal properties of epoxy nanocomposites

Summary

Introduction

Epoxy resins belong to a class of highly cross-linked thermoset polymers used most often with reinforcing fibers in a wide range of composite applications, e.g., automotive, aerospace, and pressure vessels [1]. They show a high specific strength, high modulus, dimensional stability, and low creep. The fracture energy can be increased by adding different modifiers to the epoxy resin, e.g., carboxyl-terminated butadiene acrylonitrile (CTBN) [2,3] These modifiers are unfavourable to strength and the glass transition temperature (Tg) [4] of modified systems. Some toughening mechanisms reported by several researchers are mainly pull-out, crack bridging, plastic void growth around bonded CNT’s and interfacial bonding [18,19,20,21]

Objectives

Methods

Results