Graphene composites: introduction and market status - Page 39

Researchers at the US Department of Energy's Lawrence Berkeley National Laboratory have found that polycrystalline graphene has quite low toughness, or resistance to fracture, despite having very high strength. 

The researchers say that while the extremely high strength is impressive, it can't necessarily be utilized unless it has resistance to fracture. The senior scientist in the Materials Sciences Division of Berkeley Lab developed a statistical model for the toughness of polycrystalline graphene to better understand and predict failure in the material. This mathematical model found that the strength varies with the grain size up to a certain extent, but most importantly it defined graphene's fracture resistance. 

Haydale's HCS has announced the commissioning of a composite pipe testing facility, that will be used to assess new graphene enhanced composites. The new facility for long term testing consists of 8 independently controlled tanks which can carry out short and long term pressure testing of composite pipes up to 500bar and at temperatures up to 80°C. The facility is versatile and can conduct short term burst pressure (STBP) tests, determine long term hydrostatic pressure (LTHP) rating as well as performing dynamic, fatigue and cyclic testing of composite pipes to a wide range of international standards including API 15S, ISO 14692 and ASTM D2992.

HCS is active in the design, development, testing and certification of reinforced thermoplastic and thermosetting composite pipes for the oil and gas industry. The new facility should enable HCS to accelerate the development and approval of new materials and designs that can be used in the construction of oil and gas pipelines. HCS is currently developing new graphene-enhanced polymer materials for use in pipeline construction and this facility will assist greatly in the testing, approval and certification of these novel materials.

The Spanish Navy will conduct a research on the use of graphene in ballistic protection systems, along with Marine Corps Eastern Tercio and the Algameca Naval Station, and the Cartagena Polytechnic University (UPCT) in Spain.

Composed of a multidisciplinary team of UPCT researchers and the Ministry of Defense’s Weapons and Material Directorate, the 18-month project will be held at the Algameca Naval Station. It includes the design and manufacturing of an Experimental Integrated Ballistic System with live ammunition, based on NATO standards, also producing a series of nanocomposites (composite materials based on nanotechnology) against ballistic impacts with live fire.

The University of Manchester and The Masdar Institute of Science and Technology declared a collaborative research program covering three innovative projects in graphene and 2D materials: composites, sensors and membranes.

The projects will be led by faculty members from both research institutions, and will respectively explore the development of novel low-density graphene-based foams for various engineering applications, inkjet-printed graphene micro-sensors for energy and defense applications, and graphene-enabled ion exchange membranes for desalination. 

Researchers at the Korean Institute of Science and Technology (KIST) have developed a highly heat-resistant and high-strength resin based on chemical graphene oxide processing and mixing with universal epoxy. The new material is expected to contribute to the production of lightweight aircraft and rockets.

An epoxy resin is a material that stabilizes the structures of carbon composite materials.The institute found that multiple amine groups present around graphene oxides bond with epoxy resins to result in a number of cross-linked bonds and a 240% improvement in cross-linking density.

Sunvault Energy and Edison Power Company announced that it recently conducted a number of tests on its graphene reinforced plastic technology. Sunvault has created a Graphene Reinforced Plastic that is cost effective and with potential uses that could change the landscape of plastics utilization. This revolutionary material can give products increased endurance but with the weight and simplicity of plastic. In addition to the material's many consumer advantages, it also has some protective attributes that are truly impressive.

Two video presentations were made, the first demonstrated the ability of the graphene reinforced plastic to stop a collection of 22 caliber and 45 caliber bullets, before demonstrating in the second video presentation the ability to stop the most commonly faced weapon of aggression in the military: the AK47.

Researchers have reported a graphene-based material with special electric properties, which might enable the production of better energy storage devices. The material follows the predictions of physicists from the University of Luxembourg that three years ago had theoretically predicted the unusual characteristics of a particular composite material. These calculations could now finally be confirmed by experiment in cooperation with the Centre de Recherche Paul Pascal in Bordeaux, France, and resulted in the discovery of a so-called high-k-material, which might enable the production of better energy storage devices the basis for smaller, faster and more efficient electronics.

Earlier calculations indicated disappointing results - certain compound materials made of polymers and flaky graphene, as opposed to those made of polymers and carbon nanotubes, did not increase the conductivity of the material to the degree that was generally expected until then. These were bad news that clouded graphene's perceived future in creating composites with increased conductivity. 

CPI spin-out Primary Dispersions has formed a group that aims to commercialize specialist graphene based epoxy resins for the aerospace industry. Companies in the group include Bombardier, B/E Aerospace, NetComposites, The Institute of Occupational Medicine, and Nanoforce Technology.

The project will develop a top-down technique and synthesis platform which can efficiently and cost effectively produce graphene-reinforced epoxy resins on a scale that allows for market adoption, since as of now, there are no such techniques suitable for large-scale production of graphene based epoxy resins.

Graphene 3D Lab has announced Graphene Flex Foam, a new commercial product that will be available through Graphene Laboratories’ e-commerce site, Graphene Supermarket. The new product is described as a Multilayer Freestanding Flexible Graphene Foam, that brings together a conductive elastomer composite with ultra-light graphene foam.

The foam, a highly conductive 3D chemical vapor deposition (CVD), together with the composite, brings together the best of several worlds of graphene usage. As a flexible foam, the material is both lightweight and reconfigurable, adding to ease of use and handling, with a porous structure. The Graphene Flex Foam could be used in conjunction with other graphene-related materialssuch as Graphene 3D Lab’s filament offeringsin the creation of electronics and other conductive products.

A team of Chinese researchers, led by the Central China Normal University in Wuhan, has come up with a graphene-based extraction method for aldehydes from breath, which could aid in diagnosing lung cancer. This method can effectively extract hydrophobic small molecules such as aldehydes from breath while ignoring large biomolecules such as proteins, and it can also direct the extracted aldehydes straight to an HPLC system to determine its concentration.

The extraction method is based on in-tube solid-phase microextraction (IT-SPME), in which the inside of a thin tube is coated with an adsorbent material, usually some form of polymer. When a liquid sample is injected into this tube, the analytes of interest are adsorbed by the coating as the sample flows through, after which the analytes are released by a desorber for subsequent analysis. Critical to the whole process is finding a material that will effectively adsorb the analyte of interest while ignoring everything else.