Covestro represents that, for a period of 6 months (180 days) following the day of shipment as stated in the respective transport documents, the product will meet the specifications or values set forth in chapter "Specification" above, what ever is applicable, provided that the product is stored in full compliance with the storage conditions set forth in and referenced under chapter "storage" above and is otherwise handled appropriately. The lapse of the 6 months (180 days) period does not necessarily mean that the product no longer meets specifications or the set values. However, prior to using said product, Covestro recommends to test such a product if it still meets the specifications or the set values. Covestro does not make any representation regarding the product after the lapse of the 6 months (180 days) period and Covestro shall not be responsible or liable in any way for the product failing to meet specifications or the set values after the lapse of the 6 months (180 days) period.
Applications
Bayhydur® 302 water-dispersible polyisocyanate is a solvent-free, water-dispersible crosslinking agent for two-component waterborne polyurethane coatings. Suitable coreactants are the hydroxyl-functional waterborne resins such as Bayhydrol® A-145. Bayhydur® 302 is dispersed in the aqueous resin by direct addition and under agitation just prior to use. Reaction occurs under ambient conditions. The potlife varies depending on the coreactant and NCO:OH ratio. Coatings formulated with Bayhydur® 302 water-dispersible polyisocyanate have good gloss and chemical resistance. These coatings have good flexibility while maintaining film hardness. Bayhydur® 302 water-dispersible polyisocyanate is suitable for industrial finishing, special purpose substrates, and wood furniture. Bayhydur® 302 water-dispersible polyisocyanate can also be used as an additive with waterborne dispersions to improve film properties. As with any product, use of Bayhydur® 302 in a given application must be tested (including but not limited to field testing) in advance by the user to determine suitability.
Specification
| Property | Test Condition | Value | Unit | Standard |
|---|---|---|---|---|
| NCO content | 16.8 - 17.8 | % | M105 - ISO 11909 | |
| Monomer content | ≤ 0.20 | % | M106 - ISO 10283 | |
| Dynamic viscosity | 25 °C | 1,600 - 3,000 | mPa·s | M014 - ISO 3219/A.3 |
| Color | Hazen | ≤ 100 | M017 - EN 1557 |
Typical Values
| Property | Test Condition | Value | Unit | Standard |
|---|---|---|---|---|
| Flash point | 194 | °C | Pensky-Martens Closed Cup (ASTM D-93) | |
| Color | colourless to yellowish |
Storage
Bayhydur® 302 should be stored in tightly sealed original containers and protected from moisture, heat, and foreign materials. Processability of this product can be adversely affected by contamination. Recommended storage temperature is at room temperature (approximately 77°F/25°C).
Storage time
Labeling and statutory requirements
This product data sheet is only valid in conjunction with the latest edition of the corresponding Safety Data Sheet. Any updating of safety-relevant information – in accordance with statutory requirements – will only be reflected in the Safety Data Sheet, copies of which will be revised and distributed. Information relating to the current classification and labeling, applications and processing methods and further data relevant to safety can be found in the currently valid Safety Data Sheet.
