Graphene-Polymer Composites II

Dear Colleagues,

The mechanical, electrical, thermal, magnetic, optical and biological properties of graphene have attracted a significant amount of attention from the research community since the isolation of single-atom-thick graphene layers by Geim and co-workers in 2004. Presenting a very high surface-to-volume ratio, relatively simple processability and low cost, graphene and graphene-based materials (GBMs) were soon identified as promising nanofillers for polymer matrices. Reports have shown notorious property enhancements for graphene-polymer composites (GPC) at very low filler loadings. Uses of GPC in varied fields, such as energy, electronics, catalysis, separation and purification, biomedicine, aerospace, tribology, etc., have been demonstrated and, in some cases, put into industrial practice. However, challenges still exist. Platelet agglomeration within the polymer matrix is often seen to hinder performance improvements. Poor interfacial adhesion between filler and matrix is also a limiting factor in many systems, demanding the tuning of the surface chemistry to promote physical or chemical interactions with the polymer chains. The range of routes for the fabrication of GBMs, leading to different morphologies, oxidation states, and degrees of platelet exfoliation, have an impact on the final properties of the composites that has not yet been fully addressed. Some argue that the potential of graphene, and its advantages in relation to other nanofillers, has not yet been fully demonstrated for polymer composites. On the other hand, recent findings suggest that some graphene forms are potentially biodegradable and biocompatible, which constitutes a major advantage, compared for example with carbon black or some forms of carbon-nanotubes, which have been demonstrated to be carcinogenic. Further studies are required, concerning not only the biological properties of GBMs, but also their potential applications in multiple fields.

This Special Issue invites original papers and reviews reporting on recent progress in the following areas:

• Chemical and physical surface modifications of graphene and GBMs for improving dispersibility and compatibility with polymer matrices.
• Fabrication methods of GPC in coating, film, bulk or particulate forms.
• Properties of GPC (chemical, mechanical, thermal, electrical, magnetic, etc.).
• Applications of GPC.
• Biological properties of GBMs and GPC (biocompatibility, biointeractions, environmental toxicity, etc.).

It must be noted that the term “composite” should be understood here in its broader sense, describing a material, of any geometry and size, made of two or more constituent materials that do not lose their individual identities when combined.

Dr. Artur Pinto
Prof. Dr. Fernão D. Magalhães
Guest Editors