WACKER, the Munich-based chemical company, will again be showcasing a large number of product innovations and technologies in the silicone chemistry sector at the 18th International Trade Fair for Plastics and Rubber K 2010. Under the motto “Dedicated to Performance,” WACKER will present highly elastic silicone elastomers for engine mounts, high-performance adhesives for engine oil pans, solid silicones with low sliding friction, high-impact modifiers for epoxy resins, and a novel modular system for silicone encapsulants, to name but a few examples. Also spotlighted will be new, UV-activated silicones developed for the health care, electrical engineering and electronics sectors, which, by virtue of an innovative crosslinking technology, cure at room temperature without any emissions. Live demonstrations with an ENGEL (Austria) injection-molding machine and an interactive stand presenting information about innovative materials for regenerative energy sources (“Powered by WACKER”) will round off WACKER's presence.
WACKER will showcase its comprehensive silicone expertise on 333 square meters at the K. The third-largest silicone manufacturer in the world will be presenting around 1,000 products and 20 fields of application. Also, 60 WACKER experts will be on hand to talk to and answer questions from customers and other visitors. The number of new products going on show is equally impressive: no less than a dozen innovations will be presented at the K for the very first time. “The range of products and services we are showcasing at K 2010 is remarkable and attests to the innovative strength of Wacker Chemie,” says Dr. Bernd Pachaly, head of the Engineering Silicones Business Unit at WACKER SILICONES.
WACKER's presence this year will concentrate on three areas of competence: Silicone Elastomers & Plastics, Health Care, and Power Generation & Electrical Insulation. “WACKER has grown strongly in these areas in recent years, and has further boosted its position in its target markets,” Pachaly points out. The best example is that of the new UV technology. Two years ago the revolutionary curing technology was first presented to the public. Since then, the technique – where brief irradiation with UV light is sufficient to activate curing – has become a bestseller. “WACKER is now offering UV-activated silicones for a large range of applications,” explains the silicones specialist. “The K is an ideal platform for us to present such innovative technologies and demonstrate our extensive silicones competence.”
Few other plastics are as versatile and have such a great depth of value-added as silicones. The all-rounder does not just offer significant processing advantages over other plastics; an exceptional range of product characteristics means that – due to the increasing demands on end products – silicones are gaining ever more of a foothold in many sectors. For Axel Schmidt, responsible for the Rubber Solutions business team, silicones are therefore the material of tomorrow: “Megatrends such as energy efficiency, mobility, urbanization and growing affluence call for increasing performance in materials. Thanks to their versatility and their huge development potential, WACKER silicones can be found in many future-oriented and trend-setting applications. Thus, they offer our customers genuine added value.”
SILPURAN® 2149: UV-activated Silicone Adhesive for Wound Dressings
At K 2010, WACKER will unveil several new UV-activated silicone rubbers. One of them, SILPURAN® 2149 UV, is a pourable, two-component, addition-curing silicone adhesive which can be used for wound dressings and health care applications.
The adhesive contains a UV-sensitive curing agent. Irradiation with ultraviolet (UV) light converts the agent into its active form, whereupon the crosslinking reaction starts. In contrast to conventional addition-curing silicone products which utilize heat-activated catalysts, the new silicone adhesive cures at room temperature and on its own after the curing mechanism has been triggered with UV light. The curing time can be individually set via the UV radiation dose and the process temperature.
Processors benefit from the new curing technology in a number of ways. As the crosslinking reaction only starts when the uncrosslinked material is irradiated with UV light, SILPURAN® 2149 UV has a large processing window despite its high reactivity. At the same time, processors can cure their products faster and shorten their process times. Since the silicone does not have to be oven cured, even thermally sensitive substrates can be coated with the new adhesive coating. Considerable energy cost savings can also be made.
In particular, the UV-activated silicone adhesive is ideally suited for the manufacture of wound dressings. It forms a thin layer between the multi-layer composite and the skin. The silicone helps to create a moist environment that is beneficial for the wound-healing process. The adhesion is so soft that removing or changing the dressing is possible without impairing the skin. The dressing can be removed and changed painlessly, i.e. a-traumatically, without re-opening the healing wound. SILPURAN® silicones do not contain organic plasticizers. They also withstand radiation and are easy to sterilize. All products in this range are certified according to selected tests of ISO 10993-1 and USP (United States Pharmacopoeia) Class VI standards for biocompatibility.
New UV-activated Silicone Gel for the Electronics Industry
The ever-growing number of electronic automotive components,
such as microchip-based control systems, require protection against high-frequency vibrations, moisture, corrosion and thermomechanical stress.
Based on the company’s tried and tested silicone gel SilGel® 612, WACKER developed a new grade: SilGel® 613. It was designed to give customers a silicone gel with processing properties that are as versatile as possible. For instance, SilGel® 613 has a viscosity of 200 mPa s compared to SilGel® 612’s 1,000 mPa s, thus exhibiting greatly enhanced flow behavior. A further advantage is the improved mixing ratio of this silicone gel type (comprising two components: A and B). Compared to SilGel® 612’s 1:1 mixing ratio, SilGel® 613 offers 10:1. Modifying the ratio in this way makes mixing simpler and more thorough.
The product’s modular design offers customers two curing options. The first is “conventional” oven-curing. The second is to use a UV-catalyzed product, which is flash-cured by UV light in a matter of seconds at room temperature, drastically reducing production-process cycle times. Such flexible process control underscores the high quality offered by WACKER’s SilGel® 613 silicone gel, since customers can define their own gel time. For customers, the main advantage of switching from the oven process to the UV option is extremely fast curing. The end product’s properties remain constant, despite the change in curing process.
Highly Elastic Silicone Elastomers for Engine Mounts
How can materials cope with the growing challenges of automotive engineering? A possible answer is ELASTOSIL® R 101, which WACKER will be showing at K 2010.
Easily processed by injection molding, ELASTOSIL® R 101 offers a number of advantages over organic polymers. These include excellent low-temperature properties that guarantee flexibility down to –50°C, and heat stability up to 180 °C, which can be improved further with heat stabilizers. A special plus is that its mechanical and dynamic properties remain constant over a wide temperature range.
ELASTOSIL® R 101 has been specifically developed for the automotive industry. With a Shore A hardness of 25-65, this new product series has a high rebound resilience that comes close to that of a metallic spring. This elasticity remains constant over the lifetime of the engine. ELASTOSIL® R 101 possesses optimized damping behavior and excellent long term fatigue resistance. Such grades are particularly ideal for applications in engine mounts, where the silicone damps engine vibrations and thus makes for a smooth and stable drive.
New Silicone Adhesive for Automotive Plastic Oil Pans
Thanks to their great versatility, WACKER silicone elastomers find use in almost all industries, from mechanical engineering through electronics and textiles, to the construction sector and, especially, in automotive applications. With ELASTOSIL® 76540 A/B, WACKER now offers the automotive industry an innovative silicone adhesive with high resistance to oil, heat and blow-by gases.
The room-temperature-vulcanizing (RTV), two-part silicone, developed jointly with the INPRO, a joint venture of BASF, Daimler, Siemens, ThyssenKrupp, Volkswagen, and the Federal State of Berlin in Berlin, is extremely robust. Even when immersed in organic liquids such as engine oil at over 100 °C, the silicone sealant shows hardly any swelling and retains its mechanical strength. Consequently, it bonds extremely reliably and durably to a variety of polymers and metals.
These properties can be exploited to provide new automotive solutions, e.g. in engine construction. Instead of mounting oil pans mechanically by screwing them to the engine body, sealing them permanently with silicone adhesives is an option. WACKER’s new silicone adhesive ELASTOSIL® 76540 A/B provides both the seal and the adhesion. According to INPRO, this adhesive offers optimum bond strength and leak-tightness when used for the ideal material combination of aluminum and Ultramid® – a polyamide supplied by the BASF chemical group.
As a sealant and adhesive, ELASTOSIL® 76540 A/B can be used wherever there’s a need for high heat durability and resistance to organic chemicals. Alongside the bonding of Ultramid® oil pans, other applications are available where metals or metal parts must be flexibly and durably bonded to polymers – for example in transmissions, clutches and cooling circuits.
Silicone elastomers with low surface friction
At K 2010, WACKER will also introduce novel solid silicone rubber grades that cure to elastomers of very low surface friction. The grades presented are the ELASTOSIL® R plus 4366 series for extrusion, the ELASTOSIL® R plus 4066 grades for molding and SILPURAN® 8630/60, a high-purity silicone product developed specifically for medical applications.
The low friction effect of these solid silicones is based on a special formulation concept that circumvents the drawbacks of traditional oil-exuding silicones. The new silicone products are ideal for applications in food and medical technology. The new solid silicone rubber grades are conducive to the production of molded parts and semi-finished products that have an intrinsically lubricious surface. Unlike with traditional oil-exuding silicones, no oily silicone film forms at the surface. At the same time, the elastomers are characterized by very high tear strength and good, well balanced mechanical properties overall.
GENIOPERL®: highly efficient impact modifier for epoxy resins
Additionally, WACKER will unveil a powder additive that significantly improves the impact strength of epoxy resins without compromising their mechanical strength or heat resistance. This dispersible product, sold under the name GENIOPERL® P52, is efficient even in small amounts. Epoxy adhesives containing GENIOPERL® P52 can withstand heavy stresses caused by shock and vibration.
Impact-strength modification reduces this brittleness of epoxy resins. With GENIOPERL® P52, for example, the layers of adhesive can be rendered much more durable and reliable.
Additional Product Highlights at K 2010:
• ELASTOSIL® LR 3092/65 and ELASTOSIL® R plus 4060: Silicon elastomers with low compression set for intercoolers, turbochargers and spark plug boots
• ELASTOSIL® R 770: novel silicone rubbers for applications with high fire-safety requirements
• ELASTOSIL® R plus 4370 & ELASTOSIL® R plus 4070/60:
new self-adhesive HCR silicone rubbers for hard-soft combinations
• ELASTOSIL® LR 3040: fast-curing liquid silicone rubber with high tear strength
• POWERSIL® UV: UV curing technology for high-voltage applications
• POWERSIL® Fluid TR20: silicone fluid heat transfer media for high-performance transformers
• GENIOPLAST® Pellet S: high performance additive for compounding thermoplastics
• Customized Colors: new color mixing service for silicones
Visit WACKER at K 2010 in Düsseldorf. You’ll find us in Hall 06, Booth A10.