Experimental and Prediction Study of Displacement-Rate Effects on Flexural Behaviour in Nano and Micro TiO2 Particles-Epoxy Resin Composites.

George Papanicolaou,Aikaterini Manara,Lykourgos Kontaxis

doi:10.3390/polym12010022

Abstract

Epoxy resin composites with different weight fractions of TiO2 microparticles (1%, 5%, 10%, 15%, 20%) and of TiO2 nanoparticles (0.5%, 1%, 2%, 3%) were prepared. The particle size of the nanoparticles was averaged around 21 nm while the particle size of the micro TiO2 particles was averaged around 0.2 μm. The morphology of the manufactured particulate composites was studied by means of scanning electron microscopy (SEM). The mechanical properties of both nanocomposites (21 nm) and microcomposites (0.2 μm) were investigated and compared through flexural testing. Furthermore, the effect of displacement-rate on the viscoelastic behavior of composite materials was investigated. The flexural tests were carried out at different filler weight fractions and different displacement-rates (0.5, 5, 10, 50 mm/min). The influence of TiO2 micro- and nanoparticles on the mechanical response of the manufactured composites was studied. For micro TiO2 composites, a maximum increase in flexural modulus on the order of 23% was achieved, while, in the nanocomposites, plastification of the epoxy matrix due to the presence of TiO2 nanoparticles was observed. Both behaviors were predicted by the Property Prediction Model (PPM), and a fair agreement between experimental results and theoretical predictions was observed.

Highlights

In the past few decades, epoxy resin has been used in several applications, such as surface coatings, adhesives, painting materials as well as electronic devices
Since epoxy resin is characterized by low mechanical properties in comparison to traditional structural materials, it is usually filled with several types of reinforcements
The main parameters affecting the mechanical properties of epoxy–matrix composites are the filler concentration, the adhesion of the filler to the epoxy matrix, the particles dispersion within the resin, as well as the shape and size of the reinforcing filler

Summary

Introduction

In the past few decades, epoxy resin has been used in several applications, such as surface coatings, adhesives, painting materials as well as electronic devices. Since epoxy resin is characterized by low mechanical properties in comparison to traditional structural materials, it is usually filled with several types of reinforcements. This modification affects amongst others, the deformation mechanism of the resulted composite. The main parameters affecting the mechanical properties of epoxy–matrix composites are the filler concentration, the adhesion of the filler to the epoxy matrix, the particles dispersion within the resin, as well as the shape and size of the reinforcing filler. Scientists attempted to use nanoparticles, as fillers, in an effort to increase the mechanical properties of the epoxy resin and . Nanoparticles, that are being used, are carbon nanotubes (CNTs), silica clay, SiO2 , Al2 O3 , and TiO2 [1,2,3,4,5]

Methods

Results

Conclusion