materials selection
The most important consideration when choosing polyurethanes for a particular application is the physical properties. There are a wide variety of prepolymer and curative systems available each with their own set of physical properties. Choosing a casting system can be a difficult job. Typically, that is why most processors will choose more than one material type to test for a new application.
types of polyurethanes:
Cast Polyurethanes based on TDI, MDI,PPDI, polyethers, polyesters and polycaprolactones as building blocks, offer a wide variety of applications and advantages.
Polyethers perform well in dynamic applications and in hydrolytic environments. They are extensively used in applications such as die-forming pads, press brake dies, die springs, fork lift tires, roller coaster wheels, rolls for steel and paper mills.
Polyesters have superior cut, tear and abrasion resistance as well as better resistance to oil and solvents. Typical applications include hydraulic seals, scraper blades, rolls for graphic arts, pipeline pigs, chute liners, etc.