Desmodur E 28 is a polyisocyanate prepolymer based on diphenylmethane diisocyanate (MDI).
Product description
Applications
As corrosion-resistant primers, coatings based on Desmodur E 28 polyisocyanate can be formulated to contain zinc as zinc-rich primers that give galvanic protection. To ensure satisfactory intercoat adhesion, recoating intervals must be determined. The high NCO content of Desmodur E 28 also makes it an important curing agent for two-component systems. Desmodur E 28 polyisocyanate is an outstanding material for moisture-curing one-component formulations and is highly recommended to prime and seal porous substrates. Clear formulations of this type are effective dust-binding impregnants as well as sealers for cement and other substrates because they can protect the substrate from chemicals, deicing salt, and mineral oils.Coatings based on Desmodur E 28 polyisocyanate are also used for mold releasing in the building and construction industries. Because of their good resistance to alkalis, they are suitable adhesion primers for solvent-free coating compositions based on Desmodur polyisocyanates, Desmophen polyesters, and Desmophen polyethers. Appropriate catalysts may be added to coatings formulated with Desmodur E 28 to influence the curing reaction rate. As with any product, use of Desmodur E 28 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 | 15,5 - 17,5 | % | ||
| Viscosity | at 25°C | 5,200 - 7,600 | mPa∙s |
Typical Values
| Property | Test Condition | Value | Unit | Standard |
|---|---|---|---|---|
| Flash point | (PMCC) | 460 | °F | |
| Equivalent weight | avg. (as supplied) | 255 | ||
| Appearance | Brown liquid | |||
| Specific gravity | at 20°C | 1,14 | ||
| Solids | 100 | Wt. % | ||
| Weight per Gallon | at 25°C | 9,5 | lb. |
Solubility / thinnability
Desmodur E 28 polyisocyanate is readily soluble in esters, ketones and aromatic solvents. Alcohols react with polyisocyanates and should not be used. Only dry solvents and pigments should be used with Desmodur E 28 polyisocyanate resin.
Storage
Desmodur E 28 polyisocyanate should be stored in cool areas in tightly closed containers protected from moisture.
Storage time
The shelf life is six months after receipt of material by customer.
Health and Safety Information
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.
Disclaimer
General
The manner in which you use our products, technical assistance and information (whether verbal, written or by way of production evaluations), including any suggested formulations and recommendations, are beyond our control. Therefore, it is imperative that you test our products to determine suitability for your processing and intended uses. Your analysis must at least include testing to determine suitability from a technical, health, safety, and environmental and regulatory standpoint. Such testing has not necessarily been done by Covestro, and Covestro has not obtained any approvals or licenses for a particular use or application of the product.
Unless we otherwise agree in writing, all products are sold strictly pursuant to the terms of our standard conditions of sale which are available upon request.
All information and including technical assistance is given without warranty or guarantee and is subject to change without notice. It is expressly understood and agreed by you that you assume and hereby expressly release indemnify us and hold us harmless from all liability, in tort, contract or otherwise, incurred in connection with the use of our products, technical assistance, and information. Any statement or recommendation not contained herein is unauthorized and shall not bind us. Nothing herein shall be construed as a recommendation to use any product in conflict with any claim of any patent relative to any material or its use. No license is implied or in fact granted under the claims of any patent.
Non Medical and non Food Contact
This product is not designated for the manufacture of a medical device or of intermediate products for medical devices (1). This product is also not designated for other specifically regulated applications (e.g. including cosmetics, plant protection, fertilisers, plant strengtheners, food processing, food contact and others). If the intended use of the product is for the manufacture of a medical device or of intermediate products for medical devices or for other specifically regulated applications Covestro must be contacted in advance to provide its agreement to sell such product for such purpose. Nonetheless, any determination as to whether a product is appropriate for use in a medical device or intermediate products for medical devices, for Food Contact products or cosmetic applications must be made solely by the purchaser of the product without relying upon any representations by Covestro.
1) Please see the Guidance on Use of Covestro Products in a Medical Application document.
Sample
Any samples provided by Covestro are for testing purposes only and not for commercial use.
Typical value
These values are typical values only. Unless explicitly agreed in written form, they do not constitute a binding material specification or warranted values
Contact
Please use our contact form or contact us directly by sending an e-mail to technical-datasheets@cx.covestro.com .
