High-Temperature Resistant Adhesives and Coatings
- PDF / 1,731,741 Bytes
- 6 Pages / 595.276 x 790.866 pts Page_size
- 43 Downloads / 223 Views
High-Temperature Resistant Adhesives and Coatings Heares, a Nolax start-up company, offers newly developed water-based adhesives and coatings that are resistant to extreme temperatures up to 900 °C. The products show good adhesion to fiberglass fabrics, metal or aluminum foil and are easy to apply.
Markus Läpple, Dominik Fuhrer
For bonding in the high-temperature range special adhesives are required, since the organic substances of conventional formulations are broken down and escape when the temperature is increased. In the process, the adhesive strength continues to decrease until the bonded joint finally fails completely. The newly developed adhesives and coatings from Nolax/ Heares are suitable for highly heat-resistant and flexible composites, as well as for rigid heat protection components. In addition to the high heat resistance of the composites, the heat barrier and heat shield function of the substrates were also significantly improved. Thus, the heat insulation function of a substrate is increased by 200 °C (IR method) by the coatings. The new adhesives and coatings are easy
Adhesive
to apply (blade, roller, nozzle or spray systems) and are resistant to all vehicle fluids. There are already tested and certified products on the market that are finding their first applications in the automotive industry, especially in the exhaust tract.
Heat protection in the engine and battery High temperatures in the engine are desirable from an ecological point of view but lead to enormous problems for components such as cables and hoses. Heat protection sleeves are available to protect these components. These are already presently exposed to increased heat stress, but will continue to do so in the future, and age faster than desired. Typically, heat
protection sleeves consist out of a composite of fiberglass fabric and aluminium foil bonded with silicone or one-component (1C) polyurethane (PU) systems. These conventional adhesives reach their limits at temperatures above 180 °C, while the adhesive developed by Nolax and Heares withstands temperatures of 400 °C over the long term (Table 1).
Silicone resin emulsion Chemistry and principle Based on the silicone technology, a silicone resin emulsion was developed that was previously unknown in the field of adhesives. The patent application for Heares is already filed (WO2018158407A1 water-based adhesive). ●●
Long-term temperature resistance
Application
Nolax/Heares silicone resins
400 °C
Aqueous system via blade, roller, nozzle, spray systems
Standard 2C silicone
280 °C
Solvent based system via blade, roller systems (complex solvent recovery/combustion)
Standard PU dispersion (not cross-linked)
180 °C
Aqueous system via blade, roller, nozzle, spray systems © Nolax
Table 1 > Comparison of high heat-resistant adhesives 24
adhesion 3 I 20
© Wacker Chemie AG
Silicone resins are highly branched polysiloxanes in a 3D network with remaining functional groups as shown in Figure 1. After application of the aqueous formulation, the coated substrate or laminat
Data Loading...
