Hierarchy classification:

1. top of the aat hierarchies
2. Materials Facet
3. Materials (hierarchy name)
4. materials (substances)
5. [materials by composition]
6. organic material
7. elastomer
8. [elastomer by composition or origin]

Anotations

Scope note:

Copolymers of diisocyanate with polyester or polyether. Urethane is the strongest available elastomer, and has good abrasion resistance. Applications include parts requiring high wear resistance, such as wheels, heels, and bumpers.