Exfoliated Graphite Reinforced PMMA Composite: A Study on Nanoindentation and Scratch Behavior

Abstract

The present work aims to compare the scratch hardness (H s ) with the indentation hardness (H IT ) obtained from nanoindentation measurements of exfoliated graphite/poly (methyl methacrylate) (EG/PMMA) composites. EG/PMMA composites with thickness 50 μm each were produced by in situ melt mixing method. Scratch hardness was measured from the scratch width formed at low applied load during the course of the scratch measurements. The measured scratch hardness values were compared with the indentation hardness. There is a good correlation between the scratch hardness and the indentation hardness at low indentation depths, with a linear relationship between hardness and the reinforcement content of exfoliated graphite.

Advanced multifunctional graphene aerogel – Poly (methyl methacrylate) composites: Experiments and modeling

“…In this work, a 2.50 vol.% graphene yields a maximum hardness of 462.5 MPa, which is significantly higher than the first benchmark result (153.1 MPa at 0.6 wt.% graphene) reported by Das et al [65]. However, at the same graphene loading, the microhardness of the GA-PMMA composites is still lower than that of the graphene-PMMA composites prepared from high-quality exfoliated graphite [57] (as compared in Fig. 3).…”

“…When the graphene content ranges from 0.67 to 2.50 vol.%, the electrical conductivity of the composites increases dramatically from 0.160 to 0.859 S/m, which exhibits an improvement of more than 13 orders of magnitude compared to that of pure PMMA (10 À14 S/m [50,54,55]). Besides, even at only 0.67 vol.% graphene, the electrical conductivity of 0.160 S/m can be a sufficient level for electromagnetic interference materials [56][57][58][59].…”

Transparent cyclic olefin copolymer/silica nanocomposites

“…Wei et al ., in their study on ultrahigh molecular weight polyethylene (UHMWPE)/MWCNT composites, have reported that the COF decreases with increasing weight fraction of carbon nanotubes in the composites. Chakraborty et al . noticed the same phenomenon, i.e.…”

The effects of functionalization on the thermal and tribo-mechanical behaviors of neat and grafted polyethylene nanocomposites

“…Because of their high scratch hardness values, these grafted materials exhibit greater resistance to plastic deformation and showed a reduction in friction coefficient in the range of 0.4–0.6, 0.3–0.4, and 0.2–0.3, respectively. Nanomechanical and nanotribological results also show that there is strong correlation between indentation and scratch hardness of neat polymers and nanocomposites .…”