Graphene thermal conductivity - introduction and latest news - Page 12

The graphene-enhanced composites market is on the rise with many applications popping up around the world. While graphene-enhanced composites are exciting and yield properties like a substantial mechanical strength and conductivity boost, other advanced materials are being developed worldwide to compete or complete graphene's attributes.

One such fascinating material is an artificial dragline spidersilk, developed by an Israel-based startup called Seevix Material Sciences. We contacted Dr. Shmulik Ittah, Co-Founder and CTO at Seevix Material Sciences, to give us a short review of the Company's promising material. Dragline spidersilk is known as an extremely strong fiber, that also manages to be highly elastic and stretchable. In fact, it can stretch up to 30% of its initial length. Spider silk is thus a unique phenomenon in the materials world, toting two such seemingly contradictory properties which usually do not co-reside in one material, whether natural or synthetic.

Directa Plus, producer and supplier of graphene-based products for use in consumer and industrial markets, has announced it has entered into an exclusive collaboration agreement with Arvind Limited, India’s leading textile-to-retail-and-brands conglomerate, to infuse Directa Plus’ G+ graphene-based products into their denim fabrics.

Directa Plus’ graphene-based products can be used in a variety of ways to alter or enhance the properties of conventional Denim fabrics, and to produce ‘smart’ clothing for different purposes and environments. End-users benefit from the thermal and electrical conductivity and bacteriostatic properties of G+, such as thermal regulation, heat dissipation, energy harvesting, data transmission and no-odor effect.

Advanced materials company First Graphene has announced that it has entered into a binding Memorandum of Understanding with SupremeSAT for the development of graphene-enhanced components for SupremeSAT's Miniature Satellite Assembly Project. The collaboration with FGR will aim to develop graphene-enhanced components, for both strength and weight reduction, and also heat and radiation shielding.

SupremeSAT is working on the Project with EnduroSAT of Bulgaria. Two leading universities in the USA will be joining this project shortly. The Project will test satellite interconnectivity and data exchange between satellites and a data relay within a constellation. Initially a duo of 1.5U Cube Satellites will be assembled at SupremeSAT's Satellite Assembling facility - Pallekele - Kandy, with hardware for the satellites, training and other variants of engineering support coming from EnduroSAT.

Archer Exploration Limited recently announced a Collaboration Agreement with Flex-G (FlexeGRAPH) to jointly develop graphite and graphene based advanced materials for the thermal management of electric vehicle batteries, internal combustion engines, and high-performance computing systems.

The agreement includes advanced materials development, processing, evaluation and characterization, and in particular focuses on the development of thermal management applications using materials from AXE’s Campoona project.

Sweden-based Graphematech, a startup company that develops and sells novel graphene-based nanocomposite materials and services, has announced the development of a scalable method for coating polymer powder and granular with a layer of its Aros Graphene. The Company sees this is a major boost to the polymer composites industry.

This newly developed method is said to be very efficient for obtaining high quality dispersion of Aros Graphene additive inside a polymer matrix without the use of high shear forces in melt mixing. It enormously reduces production costs and minimizes property degradation for both the polymer matrix and the additive while maintaining high quality and homogeneous composite. The invented method can be also applied for coating polymer powder with different materials such as metals, ceramics, fibers, cellulose and more.

Mr. Xu Jiang, president and general manager of China’s XFNano, was kind enough to answer a few questions we had for him regarding XFNano’s graphene materials, technology and business. Mr. Jiang founded XFNano in 2009, and he holds a master’s degree from Nanjing University of Posts and Telecommunications.

Q: Hello Mr. Jiang, thank you for your time. Can you update us on your graphene production process and facilities?

In 2016, XFNANO put its new production line into operation, which yields an annual production capacity of 50 tons of high-quality graphene powder and 1,000 tons of graphene dispersion. We believe this can meet our customers’ demands for large quantities.

Researchers from Northwestern University have developed a hair dye based on graphene oxide that "does not include toxic compounds commonly used in hair dyes". As an added bonus, graphene-colored hair enjoys much less electrostatic frizz. Due to graphene’s thermal conductivity, the dye may even help dissipate heat on hot days. The team has filed a provisional patent for the color.

The researchers "used the biopolymer chitosan and ascorbic acid (vitamin C) to disperse flakes of graphene oxide (GO)—and the darker derivative, reduced GO—in water," which reportedly formed a smooth coating on the hair surface.

A U.S-based startup called Promethient Inc. has developed a new graphene-enhanced seat warmer technology that it says is more efficient and durable than similar available systems. The company has developed the Thermavance conductive heat transfer system, which uses conduction of heat as opposed to most of the other technologies that rely on transfer of heat through convection for the purpose of warming seats.

In the common case of convective seats, seats have to be perforated so that the air can be moved through the seating surface. This makes the surface of the seats more prone to damage from wear-and-tear and from water. In the Thermavance heat transfer system, however, Promethient uses a solid-state thermoelectric module and graphene in order to transfer heat directly to the occupant of the seat instead of first either heating or cooling the surrounding air.

Graphene 3D Lab patents a graphene-based technology to harvest thermal energy produced in Bitcoin mining. The supercomputers used to mine Bitcoin and other digital currencies give off a lot of thermal energy, which is currently mostly wasted, and so G3L's technology will be used to capture this energy and redirect it to power fridges and A/C units.

Graphene 3D Lab’s technology uses graphene-based modules to harvest the thermal energy given off by these powerful machines and redirects it into heating and/ or refrigeration solutions. Not only will G3L’s technology boost return on investment for data center operations, it is also expected to help reduce the environmental footprint of data processing.

Several companies in China are now commercializing graphene-based heating elements, embedded in wearable and other devices. Many such devices are now available, shipping globally via retailers such as Amazon and others.

Graphene is an excellent thermal conductor, and using it for heating devices is somewhat surprising. The producers of these devices explain that graphene is strong, thin and flexible, and it provides "pure far infrared radiation" and is also safer and more environmentally friendly compared to other alternatives. Whether this is actually so is an open question.