Before working with this product, you must read and become familiar with the available information on its risks, proper use, and handling. Information is available in several forms, e.g., in particular in the currently valid safety data sheets and product labels. For further information contact your Covestro representative.
Product description
Applications
Bayflex® 5253 is a moldable microcellular polyurethane foam, designed for high production molded gasket applications such as radial seal filters.
The formulated system is supplied with two liquid components. Mondur® 7000 is the component A which is a prepolymer of diphenylmethane diisocyanate (MDI), and component B Bayflex® 5253 is a polyether polyol system.Note: The phase of component B (polyol) is separated when left at rest and must be thoroughly mixed by mechanical means before use. As with other product, the user must pre-test the Bayflex® 5253 system for the application in question (including field test, etc).
Specification
| Property | Test Condition | Value | Unit | Standard |
|---|---|---|---|---|
| Material Temperature | 30 - 40 | °C | ||
| POLYOL | ||||
| Appearance | Black liquid | |||
| Mix Ratio by Weigh | Polyol/Isocyanate | 100/48 | ||
| Mold temperature | 53 ± 5 | °C | ||
| No. OH | 138 | mg KOH/g | ||
| Cream time | 26 ± 3 | seg | ||
| Dynamic Viscosity | 25 °C | 1200 | mPa.S | |
| Rise time | 78 ± 4 | seg | ||
| Specific gravity | approx. 1,05 | |||
| Free rise density | 255 | kg/m3 | ||
| Water content | max. 0,3 | Wt. % |
Storage
Avoid moisture contamination during storage, handling, and processing. For both components, pad containers with either nitrogen or dry air (desiccant cartridge or air dryer at -40°F dew point). Store poly component B from 18 °C to 30 °C (65°F to 85°F). Mix poly component to a homogenous state before use and before removing any material from container. For optimum shelf life, the recommended storage temperature for the isocyanate component is 20 °C to 35 °C (68°F to 95°F). Do not expose isocyanate component to lower temperatures – freezing may occur.
Processing
Mix Bayflex® 5253 poly before use and before removing any material from container. Nucleating the poly component will typically improve the quality of the foam. Cycle time depends on mold and curing oven temperature. Tooling with good heat transfer characteristics, such as milled aluminum, can reduce the cycle time. Use a high-quality, properly applied, wax or silicone release agent to prevent cured foam from sticking to mold surfaces. If a water-based release agent is used, sufficient time must be allowed for the mold surface to be completely dry prior to foam dispense.
Health and Safety Information
Disclaimer
Contact
Please use our contact form or contact us directly by sending an e-mail to technical-datasheets@cx.covestro.com .
