Mechanical Characterization of Extended-Chain Polyethylene (ECPE) Fiber-Reinforced Composites

Abstract

Composite materials reinforced with extended-chain polyethylene (ECPE) fibers are unlike typical stiff and brittle composite materials such as graphite/epoxy or fiberglass. The high ductility and energy absorption capacity of the ECPE reinforcing fibers gives these composites a unique mechanical response which makes them ideally suited for a variety of applications. However, this dissimilarity with more common materials requires special consideration of mechanical properties testing. In this paper, the mechanical behavior of ECPE-fiber-reinforced composites is investigated using standard composite test methods. Results of these tests are presented and discussed based on the properties of the ECPE reinforcing fibers and on the assumptions inherent in the test methods. ECPE/epoxy composites are characterized by high ultimate tensile strength, high tensile modulus, low shear modulus and strength, and viscoelastic response to loading. The highest available combination of fiber strength and strain-to-failure gives this material ductility and energy absorption capacity significantly higher than other common composite materials. Applications of ECPE composites are discussed.