Glass fiber/polypropylene composite laminates with negative coefficients of thermal expansion

In this study, the possibility of making axially low-expansive beams or tubes using polypropylene laminate composite with conventional glass fibers is demonstrated. A calculation by the lamination theory shows that the use of low-modulus polypropylene as a substitute of epoxy does not significantly reduce the axial stiffness in the ply-angle range of interest.