Choosing a Millathane® Grade?

by | Jun 25, 2021 | Educational, Informative | 0 comments

Struggling to choose the right Millathane® millable polyurethane grade

but unsure where to start? Let’s begin by discussing what Millathane is and how manufacturers produce it. Millathane emerges as a reaction product of a diisocyanate, a polyol, and a chain extender. Then, workers process it using standard rubber equipment. Moreover, they can crosslink it with sulfur or peroxide cure systems.

From there, Millathane is broken down further into TWO main categories or Grades, polyether-based or polyester-based. These millable polyurethane grades are determined by the type of polyol used. While both Polyether and Polyester Grades offer excellent abrasion resistance and strength properties, there are very distinct differences between the two. Polyether grades offer better resistance to water and humidity. Polyester grades offer better resistance to oil, fuel, and solvents.    

To choose the best Millathane grade, focus on your application’s key properties. For instance, is water or humidity resistance vital? Then, a polyether grade suits you. Alternatively, prioritize oil, solvent, or fuel resistance? In that case, go with polyester. Additionally, different grades within these categories have unique traits. Thousands of Millathane formulas exist, but the list below guides you to the right grade.

Polyester: Best Choice for Heat, Oil, and Compression Set Resistance

Millathane 66R
Properties: Oil, fuel, and chemical resistance, great low and high temp performance, strong mechanically.
Uses: Seals, gaskets, O-rings, membranes, CV-boots, dust covers, bearings for automotive, hydraulic or pneumatic parts, drive belts, rollers.

Millathane 76
Properties: Excellent dampening, vibration control, oil and fuel resistance, abrasion resistance.
Uses: Automotive parts, O-rings, seals, gaskets, diaphragms, bushings, test pads, suction cups, rubber-covered rollers, solid tires.

Millathane 5004
Properties: Low-temp flexibility, excellent oil, fuel and solvent resistance, high strength and abrasion resistance, resistance to gas permeability
Uses: Seals, gaskets, O-rings, suction cups, rollers, diaphragms, molded electrical parts, dust covers

Polyether: Best Choice for Water and Hydrolysis Resistance

Millathane 26
Properties: Meets FDA regulations for wet and dry food contact (21CFR 177.2600), hydrolysis resistance, good strength
Uses: Belting, rollers, seals, gaskets, lining, curtains, hoses

Millathane E40
Properties: Excellent abrasion resistance, low-temp performance, hydrolytic stability
Uses: Rollers, belts, seals, gaskets, military, aeronautical

Millathane 55
Properties: Low viscosity, high hardness, excellent water, abrasion, ozone resistance, hydrolytic stability
Uses: Rollers, belting, industrial wheels, seals, footwear

Millathane 97
Properties: Excellent wear properties, excellent transparency, high coefficient of friction, very good UV stability
Uses: Shoe soles, roll covers, or where transparent, brightly colored, or decorative products are desired

Millathane CM
Properties: Abrasion and water resistance, excellent low-temperature properties
Uses: Rollers, military, aircraft, belts, bushings, seals, rollers

Millathane E34
Properties: Outstanding hydrolytic stability, water and abrasion resistance, low-temp flexibility
Uses: Rollers, seals, footwear, belting, gaskets, industrial wheels

Finally, download our Millathane Polymer Selector Guide for even more details, like density and Mooney viscosity.  You can find even more information including specific Millathane formulas and safety data on our website.