Pittsburgh, June 23, 2008 -- Based on their proven performance, use of sprayable thick film coatings (TFC) based on polyurea and polyurethane chemistries has grown since their introduction in the late 1980s. One drawback to the established technology is that the TFCs are typically based on non-light- stable "aromatic" polyisocyanates, which leads to poor color retention and weathering resistance.
In addition, these systems usually contain monomeric di-isocyanates, which lead to increased industrial hygiene concerns during application. More recently, light-stable "aliphatic" polyisocyanate-based TFCs have been developed that address the color and weathering resistance needs, but may still contain monomeric di-isocyanates.
The latest aliphatic polyisocyanates and TFC formulations using them that have reduced levels of monomeric di-isocyanate - yet are still fast curing and VOC free - was the topic of a presentation by a Bayer MaterialScience (BMS) scientist at the recent American Coatings Show and Conference (ACS) in Charlotte, N.C.
The Latest Developments in Light-Stable Sprayable Thick Film Coatings was presented by David Zielinski, Principal Scientist-Industrial Coatings BMS, during the event's Polyurethanes session.
During the presentation, Zielinski offered an overview of the polymer theory behind polyurethane-based elastomeric coatings, then delved deeper into the property enhancements that are possible by using the latest aliphatic polyisocyanates to formulate TFCs.
"The traditional non-light-stable offerings have shown their limitations, not only for exterior durability but also application ease and safety," said Zielinski. "New formulating tools and approaches pioneered by BMS demonstrate that it is possible to achieve excellent physical properties including light stability, without sacrificing processability and worker safety. With the help of new polyisocyanates and co-reactants, combinations can be developed that provide a new level of weathering resistance and physical toughness."
Coating end-users are finding more utility for thick film coatings where increased barrier protection is required, like the marine and construction markets, according to Zielinski. "Now, we're seeing pick-up truck manufacturers using this technology in a continuous production, OEM environment to coat the beds," he explained. "Because of all of the advantages it offers, in the future we expect this technology will be utilized in such applications as off-road construction vehicles, the military - for blast and ballistic resistance, sporting goods, and anti-corrosion for metal structures."
Bayer MaterialScience LLC is one of the leading producers of polymers and high-performance plastics in North America and is part of the global Bayer MaterialScience business with nearly 15,400 employees at 30 sites around the world and 2007 sales of 10.4 billion euros. Business activities are focused on the manufacture of high-tech polymer materials and the development of innovative solutions for products used in many areas of daily life. The main segments served are the automotive, electrical and electronics, construction, medical, and sports and leisure industries. Our inorganic basic chemicals unit produces chlorine and related essential products for the chemicals industry. Let us give life to your vision. Bayer MaterialScience - Where VisionWorks.
Bayer Corporation, headquartered in Pittsburgh, is a subsidiary of Bayer AG, an international health care, nutrition and innovative materials group based in Leverkusen, Germany. In North America, Bayer had 2007 net sales of 8.1 billion euros and employed 16,800 at year end. Bayer's three subgroups, Bayer HealthCare, Bayer CropScience and Bayer MaterialScience, improve people's lives through a broad range of essential products that help diagnose, prevent and treat diseases; protect crops and enhance yields; and advance automobile safety and durability.
Thomas Erdner, Phone: 412-777-5200
For more information about Bayer MaterialScience's polyurethane coating technology, call 1-800-662-2927, e-mail email@example.com or visit www.bayermaterialsciencenafta.com.