Abstract

The present study explores the potential use of graphene nanoplatelets (GL‐GNPs), synthesized from glucose through a new chemical approach that is facile, economical, and eco‐friendly alternative to the conventional Hummer's method, as a nanoreinforcement in polymers for the production of light‐weight structural polymer nanocomposites. Understanding the interface character of GL‐GNPs/Polyamide 12 (PA12) nanocomposites with various nanofiller loadings and how this affects their tensile behavior, are focal points of interest. Results reveal that enhancements in polymer stiffness and strength are superior at low GL‐GNPs content than higher contents. This is attributed to higher degree of GL‐GNPs exfoliation and increased polymer phase crystallinity. Interestingly, abundant small/imperfect PA12 crystallites have grown on the GL‐GNPs surface, strongly interlinking thus the polymer and graphene phases within nanocomposites. The intensity of such crystallites in interface region is the determinant of the nanocomposites' Young's modulus, assessed at small applied tensile stress. While the GL‐GNPs‐PA12 interfacial bonding is the determinant of yield and ultimate strengths, estimated at medium and high stress levels. Overall, the 1 wt% GL‐GNPs/PA12 nanocomposite is considered the optimum. Its low density and good mechanical performance among the previously developed graphene/Polyamide nanocomposites, propose promising future for GL‐GNPs‐based nanocomposites as ecofriendly and cost‐effective lightweight structural material. POLYM. ENG. SCI., 58:1201–1212, 2018. © 2017 Society of Plastics Engineers

Owing to the unique properties of 2D graphene derivatives (2D GDs), their composites with other materials possess superior characteristics over other existing materials in the universe. Accordingly, 2D GDs-based composites have emerged as leading materials for substantial advancements of various technological industries such as energy, electronics, sensors, catalysis, environmental remediation, biomedical and structural sectors. Recently, numerous research innovations, have been developed for reliable production of 2D GDs-based composites with high quality, plentiful availability and competitive costs. The overall performance of 2D GDs-based composites is controlled by three main issues. First, the synthesis strategy of GD sheets, which determines the characteristic properties, quantity and cost of the 2D GD product. Second, the surface functionalization of GD sheets, which enhances the compatibility and chemical affinity between GD sheets and other materials within the composites. Finally, the processing method of the composite that strongly affects its microstructure, properties, productivity and cost. This makes such three processes, matters of great concern when designing 2D GDs-based composites for specific application. In this article, the structure, properties, synthesis and surface functionalization of 2D GDs are reviewed. Then, the review article discusses the research developments of 2D GDs-based composites with inorganic materials and polymers, in terms of preparation, properties and applications. Particular focus is placed on Green and/or clean production technologies. The recent research interest in the 2D GDs/multicomponent hybrid composites, with their distinctive multifunctional properties, is highlighted. Also, the new implemented applications of 2D GDs-based composites from 2021, are pointed out, as well as the currently running practical projects, which are proposing innovative futural applications prospects.

Background: Cognitive Muscular TherapyTM (CMT) is an integrated behavioural intervention developed for knee osteoarthritis. CMT teaches patients to reconceptualise the condition, integrates muscle biofeedback and aims to reduce muscle overactivity, both in response to pain and during daily activities. This nested qualitative study explored patient and physiotherapist perspectives and experiences of CMT.Methods: Five physiotherapists were trained to follow a well-defined protocol and then delivered CMT to at least two patients with knee osteoarthritis. Each patient received seven individual clinical sessions and was provided with access to online learning materials incorporating animated videos. Semi-structured interviews took place after delivery/completion of the intervention and data were analysed at the patient and physiotherapist level.Results: Five physiotherapists and five patients were interviewed. All described a process of changing beliefs throughout their engagement with CMT. A framework with three phases was developed to organise the data according to how osteoarthritis was conceptualised and how this changed throughout their interactions with CMT. Firstly, was an identification of pain beliefs to be challenged and recognition of how current beliefs can misalign with daily experiences. Secondly was a process of challenging and changing beliefs, validated through new experiences. Finally, there was an embedding of changed beliefs into self-management to continue with activities. Conclusion:This study identified a range of psychological changes which occur during exposure to CMT. These changes enabled patients to reconceptualise their condition, develop a new understanding of their body, understand psychological processes, and make sense of their knee pain.

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