Selecting a polyurethane

There are many ways to formulate polyurethane, and as the formulator develops different systems using the different properties of the different raw materials, a wide range of resins to suit different applications have evolved.

The following table demonstrates the influence that different raw materials have on the end products.

TABLE OF PROPERTIES vs. RAW MATERIALS (GENERAL GUIDE ONLY)

*Polyester is made by reacting alcohol and acid together.  Water is a by-product.  Therefore, if a polyester product is exposed to a lot of water, there is a tendency for a reverse reaction to take place.  This is why the hydrolysis resistance is poor.

It is important to select the correct resin system for each application.  Your NUI representative will assist with this.

Information required when selecting a system:

• Environment:  hydrolysis, oil, solvent resistance.
• Heat resistance.
• Performance required from the end product.
• Physical properties:  tensile strength, elongation, tear and abrasion resistance.
• UV resistance.
• Anti-fungal or anti-bacterial properties.
• Potlife.
• Shore hardness.
• Processing equipment available.
• Cost considerations.
• Equipment and resources available.

Discuss your choice of material with your NUI representative, who is kept up to date with new information and products.

NUI Key for coding of products:

BACK BONE POLYOLS

TERMINATING ISOCYANATES

HOT CURES:

For example:   Ultracast 10T90

COLD CURES: 

OTHER CODES: