FIBER PULL OUT EXPERIMENTS WITH THERMOPLASTICS

Single glass and Kevlar fibers were embedded in a ductile low density polyethylene and the forces required to pull them out were measured. The plot of debonding force vs. embedded length was not a straight line, and involved a maximum shear stress of up to 15 MPa, which was greater than the estimated shear strength of the polyethylene. Debonding appeared to be a brittle fracture process, with a work of fracture of 110 Jm-2 or less.