Thermal and Quasi-Static Mechanical Characterization of Polyamide 6-Graphene Nanoplatelets Composites.

Pietro Russo,Francesco Fabbrocino,Francesca Cimino,Antonio Tufano

doi:10.3390/nano11061454

Abstract

The growing demand for lightweight and multifunctional products in numerous industrial fields has recently fuelled a growing interest in the development of materials based on polymer matrices including graphene-like particles, intrinsically characterized by outstanding mechanical, thermal, and electrical properties. Specifically, with regard to one of the main mass sectors, which is the automotive, there has been a significant increase in the use of reinforced polyamides for underhood applications and fuel systems thanks to their thermal and chemical resistance. In this frame, polyamide 6 (PA6) composites filled with graphene nanoplatelets (GNPs) were obtained by melt-compounding and compared in terms of thermal and mechanical properties with the neat matrix processed under the same condition. The results of the experimental tests have shown that the formulations studied so far offer slight improvements in terms of thermal stability but much more appreciable benefits regarding both tensile and flexural parameters with respect to the reference material. Among these effects, the influence of the filler content on the strength parameter is noteworthy. However, the predictable worsening of the graphene sheet dispersion for GNPs contents greater than 3%, as witnessed by scanning electron images of the tensile fractured sections of specimens, affected the ultimate performance of the more concentrated formulation.

Highlights

In the last decades, the addition of nanoscale fillers to enhance specific properties of polymers has triggered intensive research activities in science and engineering
The research was focused on compounds constituted by a polyamide 6 (PA6) resin supplied by Ravago Group under the trade name Ravamid B NC as the matrix and graphene nanoplatelets (GNPs) purchased as G2Nan at Nanesa S.r.l. (Arezzo, Italy) as the reinforcing phase
This trend, reflecting a decrease in the degree of crystallinity of the matrix, which goes from 24.9% for the pure PA6 matrix to 21.1% for the compound containing 3% by weight of GNPs up to the mean value of 20.5%

Summary

Introduction

The addition of nanoscale fillers to enhance specific properties of polymers has triggered intensive research activities in science and engineering Nanoscale fillers such as nanoclays, carbon nanotubes, and graphene appear ideal to develop new multi-functional materials [1,2], but the more their potential is transmitted to the products, the better they are dispersed in the host polymeric matrix and the greater the interactions between the filler and the latter. These conditions, achievable by solution mixing and in situ polymerization methods, are usually difficult to obtain by melt compounding, which, on the other hand, is the simplest, cheapest, and most scalable technology on industrial levels [3]. It can be derived at high purity from graphite, an abundant natural resource, using relatively convenient approaches; other graphitic carbon nanofillers such as carbon nanotubes and carbon nanofibers, instead, usually require expensive and complicated equipment, as well as high energy consumption

Methods

Results

Conclusion