SHORT-FIBER-REINFORCED THERMOPLASTIC POLYURETHANE ELASTOMER COMPOSITES

Mechanical properties of thermoplastic polyurethane elastomer (TPE) re inforced with short fibers were studied. Two types of fibers were used as the discontinuous phase: an aromatic polyamide (Twaron, diameter: 12 mu m) and carbon fiber (FCI 140/90-R33-diameter: 8-10 mu m). Becaus e of processing limitations, the maximum length of both fibers, after incorporation in the composites, was reduced to 3 mm. The TPE (continu ous phase) was a polyol-polyester type [Elastollan-glass transition of short fiber segments: -42 degrees C (1)]. Both types of composites ha d fiber concentration of 10, 20, and 30 phr. Component interaction is discussed, as well as the application of a third power polynomial to e stablish a relationship between the amount of fiber added and stress a t break data. Stress-strength, tear resistance, shore A and B hardness , abrasion resistance, and compression set tests were performed. Compo sites reinforced with aromatic polyamides showed higher values in most of the tests, except in the abrasion resistance test, in which a smal ler material loss was observed.