Momentive Introduces Silver-Based Antimicrobial Elastomer for Healthcare Applications

Momentive Performance Materials Inc., one of the leading global providers of silicones and advanced materials, has announced that its StatSil* antimicrobial elastomer platform technology is being customized for a growing number of applications in the healthcare industry, as customers seek built-in antimicrobial protection for various products.

The innovative portfolio of addition curable, high consistency rubber (HCR) and liquid silicone rubber (LSR) custom compounds is based on direct incorporation of a silver-based antimicrobial additive into the base silicone elastomer. Silver's effectiveness against a variety of microorganisms, including bacteria and mold, has been demonstrated in several published studies.

"StatSil technology is an excellent candidate for manufacturers to consider for greater design flexibility and performance in applications where controlling the growth of microbes in or on the body is of concern," said Dr. Burkhard Ledig, Marketing Manager for Consumer Goods and Healthcare in Europe, the Middle East, Africa and India at Momentive Performance Materials. "Customers are impressed with the antimicrobial aspects of our StatSil materials, as well as their inherent processability."

Typically, StatSil silver-based technology does not influence processability, and the elastomers have been custom formulated to meet specific performance and processing requirements of various devices and components. Manufacture of silicone applications based on StatSil technology is possible in a hardness range between 20 and 80 Shore A.

"These new products are part of our continuing effort to support the growing global demand in healthcare applications based on silicone elastomers, room temperature vulcanizates and gels," Dr. Ledig added. In addition to proven antimicrobial efficacy, StatStil products have been shown to provide excellent resistance to a wide range of temperatures and chemicals.

Teijin Launches High-Strength & Metal-replacing All Black Aromatic Polyamide Fiber

Teijin Aramid started the production of the first all black aramid fiber, Twaron Black, in Emmen. Twaron, normally golden yellow in color due to the chemical process, now is completely black for the first time. With its three production sites in the Netherlands, Teijin Aramid is responsible for more than half of the world's production of aramid.

Aramid is difficult to dye by nature, but it is now possible to produce black threads of the same quality. Twaron is five times stronger than steel at the same weight and is often used in bullet-proof vests, ropes and cables, sails and firefighter suits. At the request of customers in the sailing and sports industries, Teijin Aramid started to investigate other colors for Twaron. Twaron Black will soon be seen for the first time in the sails of the world's largest ocean sailing race, the Volvo Ocean Race.

For the threads to become completely black, they are not dyed afterwards, like cotton fibers. The production process has been adjusted to inject the fiber with the black dye during the process. This makes it the first black aramid fiber with characteristics that are equivalent to the standard golden yellow fiber. Gert Frederiks, CEO of Teijin Aramid, explains: "With Twaron Black, it is possible to combine the special characteristics of the aramid fiber with a beautiful look. Black aramid fibers have already been produced in the world, but they do not have the same characteristics (modulus) as the standard Twaron aramid fiber."

Aramid fibers are frequently used in water sports and sportswear, but combined with carbon. "For example, you often see the golden yellow of aramid in sails on a professional yacht or the underside of a canoe. With Twaron Black, it becomes part of the whole and maintains the same characteristics."

Innovative epoxy prepreg using a bio-based resin

The formulation features CTS’s new novolac-based bio-hardener, Novocard™ XFN, which introduces a high level of renewable content to prepregs and increases impact strength by 163 percent, when compared to composite prepregs made with a conventional amine-cured resin and carbon fiber.  The aerospace, wind energy, transportation and sporting industries can use the bio-based prepreg in a range of applications due to its versatility and strength.
Novocard resin is produced with oil extracted from discarded cashew nutshells. Thermally, chemically, and water-resistant, the bio-resin delivers superior fiber wetting and improved surface appearance.  In addition to higher impact strength, Novocard-cured prepregs show improved material flow properties and processability in hot melt prepreg processes due to longer gel time when compared to traditional amine-cured epoxy systems.
Mechanical tests of a composite laminate made with a Novocard prepreg demonstrated higher shear strength and toughness of the cardanol-based matrix. The prepreg is especially compatible with carbon fibers. These results prove Novocard’s potential for other manufacturing methods such as Resin Transfer Molding, pultrusion and filament winding.

Composite Technical Services LLC is a leading manufacturer of innovative, cost effective, environmentally sustainable materials and technologies for a broad range of industries that include automotive, aerospace, construction, marine, coatings and packaging. Along with its Italian partner Cimteclab SRL, CTS has pioneered ExaPhen™, a family of bio-resins that include Novocard™ XFN and Polycard™ XFN, by taking the non-edible agricultural by-products of cashew nuts and extracting the inherent phenolic resins engineered by nature.  This highly stable phenolic structure improves thermal stability, heat resistance, fire retardancy and compressive strength.  Novocard XFN liquid novolac resins is an epoxy hardener designed to deliver improved physical and processing properties suited to composite manufacturing.  ExaPhen’s latest product line, Polycard XFN, is a new class of aromatic bio-based polyols with the ability to significantly improve the mechanical properties of bio-based rigid spray foams, sandwich panels and pour-in-place insulation systems.  CTS is dedicated to providing customers with a total solution from design concept and development of manufacturing processes to testing and production. CTS also works with customers to tailor products to unique requirements.

BASF Launches Transparent PESU Reflector for Automotive Interior Lighting Application

For the reflector used in an automotive interior lighting application, the international automotive supplier Delphi has recently started to employ a high-performance plastic from BASF. After being injection molded, the complex and highly detailed part is metalized by means of physical vapor deposition (PVD), a process with demanding requirements for the plastic. The relatively new Ultrason E 2010 MR is a polyether sulfone (PESU) characterized by its good mold release properties. The reflector is manufactured by Goletz GmbH, located in Kierspe (Germany, North Rhine-Westphalia).

For this small and complicated part, ease of demolding is especially important, since it could otherwise be removed from the injection mold only with difficulty or possibly even not at all. BASF has succeeded in combining a variety of properties in this material: it offers not only excellent mold release characteristics, but as a high-temperature material it also easily withstands a continuous service temperature of 180 °C, and briefly even 220 °C. Moreover, it exhibits very good adhesion to aluminum, the material with which it is metalized in this case. In addition, the plastic is also very transparent, allowing it to be used unrealized as well. This makes it a candidate for fryer cover applications or other design-oriented household products where this combination of properties and good appearance are a requirement. Therefore, Ultrason E 2010 MR also has the necessary approvals for food contact applications.

LANXESS & Gevo Collaborate to Develop Butyl Rubber from Renewable Biomass Feedstocks

One of the most intriguing working relationships in the search for renewable biomass feedstocks is the partnership of Gevo, a renewable chemicals company in Colorado, USA, and LANXESS, who intends to open up alternative resources for the production of butyl rubber.

Together, scientists from LANXESS and Gevo are now making good progress in producing isobutene a key raw material for butyl rubber from renewable resources. Traditionally, isobutene has been produced in steam crackers, which require various petrochemical-based materials for feedstock. But the LANXESS-Gevo partnership is now pioneering a unique method that may hold the key to the sustainable production of isobutene.

Researchers at LANXESS have now created a breakthrough dehydration process that converts isobutanol into isobutene. In this process, water is removed from the isobutanol. The result is biologically obtained isobutene. The dehydration process has not only proven to be successful in the laboratory, but has also undergone several months of practical testing in a small-scale reactor at LANXESS' site in Leverkusen, Germany. These tests have shown that the process can deliver bio-based butyl rubber that meets the rigorous standards of the tire industry, which represents 25 percent of LANXESS' sales. In the long term, bio-renewable isobutene will account for half of LANXESS synthetic rubber production at its plant in Sarnia, Canada. Heitmann stated: "As the world's largest purchaser of isobutene, it is only prudent that we seek alternate supply options from renewable sources as a counterweight to fossil fuels. It underpins our commitment to Green Chemistry."

Bayer Launches Polymer-based Blast-resistant Transparent Structural Shield for Buildings

Bayer MaterialScience LLC's Hygard® BL80 Shock-Wave Sentinel is certified with a Developmental Testing and Evaluation Designation by the U.S. Department of Homeland Security (DHS) under the Support Anti-Terrorism by Fostering Effective Technologies (SAFETY) Act.

The DHS certification recognizes Hygard® BL80 a blast-resistant transparent structural shield for buildings as a promising anti-terrorism technology. Additionally, the certification limits a building owner's legal liability for installing and utilizing the technology. 

DHS performed a thorough review of Bayer's Hygard® BL80 innovative design, product development, performance testing, and quality management systems. "The DHS sets a high threshold to qualify for this certification, both for the new solution's potential contribution to U.S. security, and confidence in Bayer's ability to effectively deliver the new technology," said Mike Gallagher, Leader, Public Sector Business, Bayer MaterialScience LLC. "Receiving the DHS Developmental Testing and Evaluation Designation for the Hygard® BL80 is tremendously gratifying."

"Hygard® BL80 is inherently transparent, lending itself to an 'open architectural appearance,' but can also be decorated as desired. We think this aesthetic flexibility in a new standard of protection will be especially pleasing for building owners who are looking for a cost-effective alternative to relocation or new construction," said Roger Rumer, Marketing Leader, Public Sector Business, Bayer MaterialScience LLC.

"Hygard® BL80's potential ability to absorb the force of an external blast to protect a structure, its occupants, and provide operational continuity for critical infrastructure makes it an appealing solution for government agencies," said Bob Pyles, Co-Inventor and Pursuit Team Leader, Hygard® Structural Integrity Systems. "We look forward to being able to contribute to our nation's safety."

Hygard® BL80 is comprised of laminated, transparent polymer panels attached to a structural steel frame that is supported on a concrete foundation. Shock-range and open-tube testing demonstrated Hygard® BL80 can withstand 80 psi peak pressure and 380 psi-msec impulse, well above the most challenging known standards. The blast-resistant structural shield is the first product launch from Bayer's Public Sector Business, which offers integrated products, manufactured according to ISO-9001 compliant processes and procedures, and services that will help government entities meet challenges through materials innovation in the areas of construction and infrastructure, health, security, sustainability and transportation.

"This Public Sector Business builds on the success of Bayer's Government Services Group, which has completed federally funded research and development projects totaling $2 million, and has commitments for another $3 million," Rumer said. "The Public Sector Business will continue to provide research and development services to fulfill government grants, but will also work directly to provide the benefits of our innovative materials to the needs of government entities."

Case Western Researchers Develop CNT Reinforced Polyurethane Blades for Wind Turbines

Efforts to build larger wind turbines able to capture more energy from the air are stymied by the weight of blades. A Case Western Reserve University researcher has built a prototype blade that is substantially lighter and eight times tougher and more durable than currently used blade materials.

Marcio Loos, a Post-doctoral Researcher in the Department of Macromolecular Science and Engineering, works with colleagues at Case Western Reserve, and investigators from Bayer MaterialScience in Pittsburgh, and Molded Fiber Glass Co. in Ashtabula, Ohio, comparing the properties of new materials with the current standards used in blade manufacturing.

On his own, Loos went to the lab on weekends and built the world's first polyurethane blade reinforced with carbon nanotubes. He wanted to be sure the composite that was scoring best on preliminary tests could be molded into the right shape and maintains properties. Using a small commercial blade as a template, he manufactured a 29-inch blade that is substantially lighter, more rigid and tougher.

"The idea behind all this is the need to develop stronger and lighter materials which will enable manufacturing of blades for larger rotors," Loos said.

In order to achieve the expansion expected in the market for wind energy, turbines need a bigger share of the wind. But, simply building larger blades isn't a smart answer. The heavier the blades, the more wind is needed to turn the rotor. That means less energy is captured. And the more the blades flex in the wind, the more they lose the optimal shape for catching moving air, so, even less energy is captured. Lighter, stiffer blades enable maximum energy and production.

"Results of mechanical testing for the carbon nanotube reinforced polyurethane show that this material outperforms the currently used resins for wind blades applications," said Ica Manas-Zloczower, Professor of Macromolecular Science and Engineering and Associate Dean in the Case School of Engineering.

In a comparison of reinforcing materials, the researchers found carbon nanotubes are lighter per unit of volume than carbon fiber and aluminum and had more than 5 times the tensile strength of carbon fiber and more than 60 times that of aluminum.

Fatigue testing showed the reinforced polyurethane composite lasts about eight times longer than epoxy reinforced with fiberglass. The new material was also about eight times tougher in delamination fracture tests. The performance in each test was even better when compared to vinyl ester reinforced with fiberglass, another material used to make blades.

The new composite also has shown fracture growth rates at a fraction of the rates found for traditional epoxy and vinyl ester composites. Loos and the rest of the team are continuing to test for the optimal conditions for the stable dispersion of nanotubes, the best distribution within the polyurethane and methods to make that happen.

The functional prototype blades built by Loos, which were used to turn a 400-watt turbine, will be stored in our laboratory, Manas-Zloczower said. "They will be used to emphasize the significant potential of carbon nanotube reinforced polyurethane systems for use in the next generation of wind turbine blades."
The research is funded by a U.S. Department of Energy stimulus grant and Bayer MaterialScience.