A comprehensive collection of news and information about composites.
Posted by: Ginger Gardiner19. November 2014
On January 30, 2014, the U.S. Patent & Trademark Office published a patent application from Apple titled "Transparent Fiber Composite."
I was intrigued when I ran across Patently Apple’s posting, “Apple Exploring new Transparent Fiber Composite Materials for Future Devices Including Wearable Computers”. The site relates that Apple Inc. (Cupertino, Calif., USA) has been experimenting with composites since 2007, and has now invented a method for manufacturing relatively transparent fiber reinforced plastic structures.
Interestingly, Mo-Sci Corp. (Rolla, Mo., USA) received a 2007 SBIR research funding award for “High-Strength and Optically Transparent Fiber-Reinforced Composites”, which describes “a need for mechanically strong composite materials of high optical quality and transparency equivalent to window glass” and achieving this “by layering a polymer matrix reinforced with glass ribbons (micron-size glass fibers with rectangular cross section) and a tough compliant polyurethane film.” Apparently Mo-Sci had already licensed technology from U.S. Patent 5,665,450 awarded to the University of Missouri and produced research quantities of glass ribbon-reinforced epoxy for high-strength window applications. The patent shows the technology’s foundation of prior art and accompanying issues, which include difficulty in matching the refractive index of materials due to variations with temperature. The Army Research Lab report, “Transparent Composite Utilizing Nonlinear Optical Polymers” specifically noted that “index-matched systems are transparent only over a narrow temperature range.”
In its application US 20140030522 A1, Apple describes matching the refractive index of the glass fiber, the sizing applied to the fiber and the resin matrix which the fiber reinforces so that the difference between them is less than .005. It also describes forming a transparent fiber-resin composite by injection molding chopped glass fibers ranging in length from 0.25 to 0.50 inch (6 to 13 mm), which can be mixed into the resin prior to injection. This method is said to enable high volume production and even distribution of the fibers in the resin. The patent does NOT disclose how Apple has overcome the RI matching challenges faced by previous developers.
A search on “transparent composites” reveals many different approaches, including bacterial nanofibers, plant nanofibers, chitin particles and polymer nanofibers, and fibers made from polymer ribbons. Transparent composites have also been made using hollow nanofibers electrospun from nylon and polyacrylonitrile (PAN), the common precursor for carbon fiber). The nylon is embedded into an epoxy matrix and the PAN into poly methyl methacrylate (PMMA). Applications claimed include protective armor and aircraft windows.
The high crystallinity of the BioMid fiber makes it more transparent than other natural fibers. SOURCE: June 2013 CT article, “Bio-composites update: Beyond eco-branding”
The RI issue may have been solved through research at Kyoto University (Kyoto, Japan). Led by professor Hiroyuki Yano, transparent nanocomposites were produced by mixing chitin particles (long-chain polymers that form insect, arachnid and crustacean exoskeletons) with acrylic resin and impregnating pulp fibers to form a composite sheet. The resulting composite showed optical transmittance over a wide temperature range.
Pulp fiber sheet before (left) and after impregnation with chitin-modified acrylic resin.
SOURCE: Hiroyuki Yano, Fumiaki Nakatsubo and Kentaro Abe, Kyoto University.
Where do we go from here? Patently Apple asserts that this technology could be applicable in both wearable computers (e.g., the iWatch) as well as integration into other products like sporting goods. In its patent, Apple says clear composites can enable lightweight, strong housings that integrate displays and even camera lenses. That almost implies a multifunctionality that would cut the number of materials and manufacturing steps used in idevice production.
Left: iWatch concept by Todd Hamilton
Right: Images from U.S. Patent US8787006 B2 awarded to Apple,
showing a sensor-packed strap as a dock for various snap in-place modules.
Multifunctionality makes me think of Airbus’ vision for the airliner of 2050, where a futuristic fuselage utilizes topology optimized advanced materials which also provide optical transparency. Though the Airbus images are clearly meant to push boundaries (I’m not convinced being able to see through the fuselage of a commercial airliner is a good idea), what if transparent composites with properties in the range of today’s carbon fiber laminates were possible? And offered selective electrical conductivity and integrated sensors? Solar cells have already been made using transparent graphene electrodes.
Airbus believes future aircraft could be built using a structure that mimics the bones of birds — light, strong and carrying load only where necessary, leaving space for oversized windows and doors, or alternatively, transparent composite laminates. SOURCE: Airbus
Concept cars are also anticipating what might be possible. For example, the GammaConcept claims to use advanced materials as a basis to develop a new visual language, featuring transparent areas to show underlying structure and engine parts. Though this concept uses polycarbonate, perhaps the next generation will opt for transparent composites.
The GammaConcept features large transparent areas, currently achieved with polycarbonate, glued to a glued onto a carbon and Kevlar fiber-reinforced aluminum chassis. SOURCE: Behance.net
Posted by: Ginger Gardiner18. November 2014
SpiderFab is one example of the new technology being driven by NASA’s Game Changing Development program. SOURCE: NASA.
The “Ultra-Lightweightcore Materials For Efficient Load-Bearing Composite Sandwich Structures” grant solicitation has been issued as part of NASA’s Game Changing Development (GCD) program. The GCD seeks to identify and rapidly mature innovative novel ideas and approaches that have the potential to revolutionize future space missions as well as provide solutions to significant national needs, like energy and manufacturing. CW has reported extensively on the composite cryotank, which is a GCD program.
Other NASA Game Changing Development programs include (from left to right):
3-D printed rocket engine parts,
Robonaut 2 with new climbing legs for zero-gravity mobility,
Made In Space’s first zero-gravity 3-D printer and
Firefly Space Systems’ low-cost small satellite launch vehicle which uses a methane-fueled aerospike engine and composite cryotanks.
SOURCE: All images sourced from NASA except Firefly sourced from aviationweek.com.
GCD issued the “Ultra-lightweight Core Materials for Efficient Load-Bearing Composite Sandwich Structures” solicitation on Oct. 24, 2014. It seeks proposals for the maturation and development of scalable methods to manufacture ultra-lightweight core materials as lower mass alternatives to honeycomb or foam cores in composite sandwich structures. Specifically:
“The development of advanced manufacturing techniques has led to the production of lightweight, hierarchical structures with the potential for use as lower mass alternatives to conventional core components in composite sandwich structures. NASA is interested in scaling up manufacturing processes to produce ultra-lightweight core materials that could be used to produce large-scale composite sandwich structures. The envisioned development effort would demonstrate that materials are a cost-effective and lighter weight alternative to conventional core materials. The overall goal of the Appendix is to develop and demonstrate scalable and cost-effective manufacturing approaches to produce ultra-lightweight core materials both as flat panels and curved structures. The resultant structures will have half or less the areal density of conventional honeycomb cores, while retaining equivalent, or better, mechanical properties.”
Materials with hierarchical structures include bone and spider silk, which achieve very high strength and/or stiffness with very lightweight. MIT’s recent 3-D printing of core materials — "Ultralight, Ultrastiff Mechanical Metamaterials” — is another example, noting that they have developed microarchitectures into the materials which are then fed into the additive manufacturing machines to create unique macroscale architectures.
The different arrangement of material structures at the various scales within hierarchical materials like bone and spider silk work in concert to perform the diverse mechanical, biological and chemical functions, which enable unique performance advantages.
SOURCE: Surface Engineering, Mawson Institute, University of South Australia (left) and Interface Journal of the Royal Society and Markus J. Buehler.
This ultralight core initiative is part of a greater Mars mission focus:
Composite sandwich structures are used extensively within the aerospace industry and in other applications where reducing weight while maintaining structural strength is important. A common use for these sorts of composites is the shrouds for launch vehicles and other key technology components that will enable our journey to Mars.
Over the next year, NASA’s Space Technology Mission Directorate (STMD) will continue to seek industry and university partnerships to assure the agency has the capabilities it needs, while helping America maintain its leadership in the technology-driven global economy. These investments will focus on in-space propulsion and advanced high-power solar arrays; robotics and avionics for outer planetary exploration, especially high-reliability and low-mass, deep ice penetration systems; advanced materials, including large composite structures; and space observatory systems, with a focus on advanced optical coating materials.
This page says NASA expects to make two awards of up to $550,000 each for this first development phase. The Game Changing Development program for STMD is managed by NASA's Langley Research Center in Hampton, Virginia. For the full original posting, click here.
Posted by: Sara Black17. November 2014
Test results for composites made with carbon nanotube carboxylic acid (CNT-COOH) and few layered graphene carboxylic acid (FLG-COOH) show that adding nanomaterials increases compression strength 13 percent vs. normalized properties and boosts CAI by 50 percent. SOURCE: Cardiff University.
The School of Engineering at Cardiff University and graphene specialist company Haydale Ltd. (Carmarthenshire,U.K.) recently announced new research demonstrating significant improvements in mechanical performance of composites, including impact resistance, using plasma-treated graphene nanoplatelets (GNP).The research was undertaken by the Cardiff School of Engineering with additional funding from the European Community’s Seventh Framework program under the Clean Sky Joint Technology Initiative, aimed at greener aircraft design. The project included the Centro Italiano Richerche Aerospaziale (CIRA), and was managed by an integrated team from CIRA, Cardiff School of Engineering and Haydale.
The research investigated graphene nanoplatelet (GNP) and carbon nanotube (CNT) reinforcement technology. The results observed in this research show a 13 percent increase in compression strength and a 50 percent increase in compression after impact (CAI) performance (see graph above), indicating that fracture mode has been positively influenced, say researchers.
A resin infusion technique was employed to produce composites containing a small percentage of nanomaterials. Significantly, the nanomaterials were surface treated using Haydale’s trademarked low temperature, low energy HDPlas plasma process, which promotes homogenous dispersion and chemical bonding, without waste. The low pressure plasma process can treat both organic mined fine powder and other synthetically-produced nanomaterial powders, producing high quality few-layered graphenes and graphene nanoplatelets. Haydale says the process can functionalize with a range of chemical groups, where the amount of chemicals can be tailored to customer needs. Good dispersion improves the properties and performance of the host resin. The plasma process does not use wet chemistry, neither does it damage the material being processed. Energy requirements are low and the process is reportedly environmentally friendly.
Ray Gibbs, CEO of Haydale, says “These exceptional results underline the potential of Haydale’s tailored, plasma functionalization process in delivering a scalable technology for the production of superior composites. We believe that by working closely with the Cardiff School of Engineering, our combined resources and expertise can significantly accelerate graphene optimization.” Professor Sam Evans from the School of Engineering, Cardiff University, agrees, saying “This research represented a fantastic opportunity for the team at Cardiff to work with graphene materials and technology. Graphene technology has enormous potential for improving the performance of aircraft materials. These initial results suggest that there may be the potential for big weight reductions in aircraft and many other applications, which is very promising.”
Let’s hope that the research comes to fruition. There are many commercialization challenges in moving beyond the lab, and costs of these GNPs has traditionally been very high, as noted by Lux Research senior analyst Ross Kozarsky in the 2013 HPC article, "Graphene: Ready for prime time?". For nanotechnology to benefit composite fabricators, the costs must come down.
One promising nanotechnology product is offered by OCSiAl (U.S. offices in Palo Alto, Calif. and Columbus, Ohio), an exhibitor at the recent CAMX conference and exhibition (Oct. 13-16, Orlando, Fla.). The company can produce single-wall carbon nanotubes (SWCNTs), trademarked Tuball, promoted as a “universal nanomodifier” additive for many types of materials, at a mass industrial scale in a reportedly continuous process. The company offers the Tuball product at the incredibly low price of $2 per gram, according to its Web site. Others are also bringing less expensive products to the market as reported in the September issue of Nanotech Magazine. Perhaps greater adoption of nanotechnology forms for better-performing composites will soon be a reality.
Posted by: Ginger Gardiner13. November 2014
Connora Technologies' Recyclamine hardener enables composites to be separated back into resin and fibers for reuse with the epoxy resin converted into a recyclable thermoplastic.
I first saw Recyclamine over a year ago in an Italian composites magazine and put it on my Blogs To-Do list. Then I saw Adesso and their Cleavamine product. Two producers of hardeners enabling epoxies to be recycled like thermoplastics? Well, yes and no. I interviewed Connora Technologies’ CEO, Rey Banatao. Here is the story.
Rey has a degree in Biochemistry from the University of California, Berkeley and a PhD in Computational Biology. He was also a postdoctoral fellow at the California Nanosystems Institute at UCLA. He co-founded Entropy Resins (Hayward, Calif.) with his brother Desi, who is also a Berkeley grad, with a Masters in Material Science and Engineering. Their goal was to develop renewable materials for performance composites. This is exactly what they have achieved over the past 6 to 7 years through Entropy’s Super Sap epoxy resins, which reduce greenhouse gas emissions by 50 percent vs. petroleum based epoxies and are made from plant-based co-products or waste from established industrial processes, so they don’t displace food crops.
Expanding on Entropy’s bio-based resins, Desi also co-founded Lingrove (San Francisco, Calif.) with Joe Luttwak of Blackbird Guitars (San Francisco, Calif.) which offers the unique expertise they have developed in prepregging and molding with biobased fabrics. Lingrove supplies natural flax fiber reinforcements and prepregs, as well as hybrids with glass and carbon fibers to achieve exceptional performance. A bicycle frame on display at CAMX 2014 (Oct. 13-16, Orlando, Fla.) has a certified 75 percent biobased content thanks to use of Lingrove's ‘Ekoa’ prepregs. As Luttwak played Blackbird’s Clara concert ukulele for me, he noted that sales of these instruments into Hawaii have picked up because they offer moisture stability for open-air performers vs. traditional tropical hardwoods, which are becoming increasingly rare and expensive. Ekoa is not just a sustainable alternative, it’s achieving a marketable advantage. Let me say that again, Lingrove can tailor a composite to look like wood and sound like wood but offer advantages in dynamic range of sound — i.e. vibration — and environmental durability not to mention lightweight. (Link to article on new El Capitan guitar.)
Back to Rey and Desi, their work with Lingrove and Entropy to certify biocontent and the carbon footprint of the composite materials and processes, including complete life cycle assessments, is now part of a growing trend in consumer goods worldwide.
It’s at this point where Connora’s founder and chief technical officer, Stefan Pastine, enters. While doing post-doctoral research at UC Berkeley under a professor who pioneered photoresist chemistry (now fundamental to micro chip patterning processes), Pastine thought to apply the concept of “designed in cleavage points” to epoxies. He then developed the chemistry to work in polyamine curing agents. Rey Banatao explains, “If you engineer it right, you can break apart the crosslinks and can get back thermoplastic molecules which allows the resin to be reclaimed…or anything bound by the resin as well.” In discussing the benefits vs. other recycling methods, such as pyrolysis (which burns away the plastic matrix), their chemical approach can maintain the reclaimed fiber’s virgin properties and length, and returns the matrix as an epoxy thermoplastic.
Pastine then traveled to China to work on nanotechnology for Adesso Advanced Materials (Wu Xi, Jiangsu Province, China). When the nanotechnology did not develop as planned, Pastine shared his recyclable epoxy technology and formed an agreement with CEO Bo Liang that Adesso would help with manufacturing and marketing of the new materials, but no exclusivity was established.
Pastine then returned to the U.S. and founded Connora Technologies. Although the original technology patents are shared by Connora and Adesso, they represent just the beggining of the journey to making the technology a commercial reality. Since 2012, Pastine has developed and patented a second generation Recyclamine technology, exclusive to Connora. Adesso is licensed to sell this and the two issued a joint press release in May, explaining their relationship and cooperation. “They are a good partner in a large market,” says Banatao, “and share our excitement about recyclable thermosets. As Connora’s technology becomes commercialized, we see Adesso as a good distribution partner to help provide access to Chinese markets, as well to provide an epicenter for recycling." Banatao adds that Connora is also working with globally positioned chemical companies, with the goal of increasing both industrial-scale supply and applications for truly recyclable epoxy resins and composites.
When asked about applications, Banatao notes that his background via Entropy has been mostly in consumer facing products, especially sporting goods (e.g. surf, skate, and standup paddle boards, etc.). This year Burton (Burlington, Vt.) is introducing a line of snowboards using Super Sap resins. “But we’ve always had an eye out for industrial applications,” he observes. Connora’s focus is really targeting these large markets, where composites are made in high volumes and generate a lot of waste. “We definitely saw Recyclamine’s potential and served as both investor and incubator for Connora,” Banatao explains. “As the effort grew, it made sense for me to take on the role of CEO. While we are working on setting up manufacturing partnerships with large chemical companies, we are also expanding our own pilot manufacturing and R&D facilities here in Hayward.”
But can Connora really produce Recyclamine on an industrial scale? “All of the chemistry we developed was unprecedented, so at first, we had to determine what was even possible…what Recyclamines could be made from, and what properties they had. Then, we had to go through several process iterations,” Banatao concedes. “But now we have made it more affordable and have also developed renewable feedstocks. We’ve also tried to get away from harmful or explosive chemistries, so our manufacturing process is safer and does not require highly specialized infrastructure. We’ve developed a whole new platform for how to make amines. This alone should be of value to the chemical industry as a whole.”
Banatao is very passionate about Connora’s ability to revolutionize composites, “Why don’t we start reengineering tomorrow’s composites so that it takes less energy to reuse them? It’s great to use recycled fibers, but what can we do to make that easier and design composites to be recyclable from the start? We (the industry) did this for thermoplastics. Why not thermosets? ” He also points out that a new process for handling composite waste, recycling, and then reusing the reclaimed materials will need development. While he and the Connora team know that reclaiming carbon fiber is currently the main economic driver of composite recycling, they are also looking for good applications of the recycled epoxy thermoplastic.
Okay, but are the original epoxies easy to work with? “Anything that uses an epoxy can use the technology," says Banatao. "We have a room temperature system that is easy to infuse with and we’ve also used it in compression molding. We also have a latent cure system for prepreg, filament winding, or pultrusion and are developing a version for high pressure resin transfer molding (HP-RTM) for the automotive industry.”
The future for this technology seems almost too large to grasp, really, if you think about Connora’s headway toward a two-minute cure cycle for the HP-RTM system and higher Tg systems which could be used in circuit boards. The Banataos have dedicated most of their careers to making composites more sustainable and environmentally friendly. With inventor Stefan Pastine and Connora Technologies, the potential now exists to change the industry on a massive scale. The question is, will the industry exploit this potential and increase composites’ competitive position vs. plastics, metal and wood?
Posted by: Ginger Gardiner11. November 2014
Material ConneXion (New York, N.Y.) is a global materials consultancy that delivers information about the latest advanced and innovative materials to designers worldwide. If you’re a designer for Addidas, Motorola or Toyota, where do you get information about cutting edge material developments? Multiple technical journals, newsletters and conferences? Perhaps, but Material ConneXion has become a favored option by many because it eliminates weeding through university- and marketing-speak, concisely highlighting a material’s innovation — e.g. new viscose fiber with 10X increase in dye absorption for reduced processing costs. It also does this with the originality, elegance and efficiency of an Apple design. Case in point, subscribers can walk through the rows of visually stunning materials in brick-and-mortar libraries around the world — which are also available online — but can also receive a box of curated wonder materials every few months via the ActiveMATTER service.
Material ConneXion was started in 1997 by George M. Beylerian, founder of the contemporary design store Scarabaeus in New York City and the Beylerian Limited brand of furniture which was acquired by Steelcase (Grand Rapids, Mich.). The other members of Material ConneXion’s executive team bring global expertise in publishing, consumer product design, architecture and industrial design. But then comes the science. Vice president of library and materials research Andrew Dent has a Ph.D. in materials science from the University of Cambridge in England and previously held research positions at Rolls Royce (London, England) — specializing in turbine blades for the present generation of jet engines — and at the Center for Thermal Spray Research, State University of New York (SUNY, Stony Brook, N.Y.), as well as performing research for the U.S. Navy, DARPA, NASA, and the British Ministry of Defense. In fact, over half of Material ConneXion’s staff are material scientists, specialists in a particular material technology (polymers, ceramics, etc.) or sustainability experts. The company seeks to bridge the gap between science and design.
Material ConneXion has over 70,000 members worldwide and advises companies, designers and engineers from offices in the U.S., Italy, Japan, Korea, Sweden and Thailand. Though many of its customers request confidentiality, it also serves many on the Fortune 500 list. Its clients include IKEA, General Motors, Fisher Price, Nike, Samsung, Samsonite and Target, as well as thousands of architects and industrial design firms.
Besides all of the innovative materials, which I love, and Material ConneXion’s modern approach, I believe its reach into the industrial design community offers value to companies in our industry. Suppliers of unique composite materials and processes should apply to have these added to the MCX library. No fee is required and submissions are reviewed by an independent jury, which adds 30 to 40 new materials to the library each month. Out of 7,500 plus materials, currently 400 are composites or materials used in composites.
“We want to receive materials submissions from composite material suppliers,” says VP of library and academic programs Michael LaGreca. “We talk to thousands of designers on a continuing basis, and want to make sure they have the latest in materials developments and potential solutions.” Companies interested in submitting materials for library selection should contact Access@materialconnexion.com .
The other opportunities I see are for composites materials to be included in Material ConneXion’s publications and technical reports and in the presentations it gives at global trade shows and conferences. For example, it exhibited at the 2014 International Boatbuilders’ Exhibition and Conference (IBEX, Sep. 30 - Oct. 2, Tampa, Fla.), displaying an on-site library of materials in the Composites Pavilion. Samples included a textile woven to be auxetic — having a negative Poisson’s ratio so that it becomes thicker when stretched, not thinner — and fabric-like material made from thin schisms of Italian stone combined with layers of adhesive, textile and resin to form a flexible veneer, less than 0.5 mm/0.02 inch in thickness and 0.4 kg/m² (.08 lb/ft²) in areal weight (which is less than a carbon fiber/epoxy twill 2/2 prepreg with 44 percent resin content). Composites could gain that type of exposure in events for other industries.
Auxetic textile woven to thicken with tensile loading (left). Applications include safety belts, straps and ballistic/blast protection, for example, this single layer of Zetix fabric after 8 grenade blasts from 1 meter distance shows a shrapnel strike point with zero penetration despite heat damage. SOURCE: Material ConneXion (left), Auxetix (Exeter, U.K.) and Advanced Fabric Technologies (Houston, Tex.).
“What we brought to IBEX is just a small sample of the materials that we think could be translated to the marine industry which are currently being used in other industries like apparel and automotive,” said MCX material scientist Sara Hoit. “This cross-pollination often provides a direct solution or sparks an idea for a new innovation.”
Flexible stone material made from real Italian stone, adhesive, fabric and resin, less than 0.5mm thick. SOURCE: Sommers Plastics Products (Clifton, N.J.)
And that is another benefit I see for companies in the composites industry — to learn about new materials that might improve or add value to their current systems and technologies or be inspired to take their materials into totally new industries and applications.