On the dynamic mechanical behavior of poly(methyl methacrylate) reinforced with Kevlar fibers

Abstract The dynamic mechanical relaxation behavior of poly(methyl methacrylate) reinforced by continuous parallel Kevlar‐49 fibers is investigated here on samples with several fiber volume fractions. The shifts in the temperature of the main relaxation of the matrix are interpreted according to free volume considerations and with the help of a thermomechanical block model. The dependence of the storage and loss moduli both on temperature and fiber content found experimentally can be reproduced by the model. It is not necessary to rely on the existence of an interphase to account for the modifications evidenced by the spectrum of the matrix, which can be explained on the basis of the two phase model.