Relationship between microstructure and tensile properties of PET/silica nanocomposite fibers

The influence of silica nanoparticles on the tensile properties of poly(ethylene terephthalate)(PET) fibers was investigated. The results showed that mechanical properties of PET fibers were improved through nano-silica incorporation. Two maxima of the modulus-strain curves of PET/silica nanocomposites (PETS) fibers are always higher than those of pure PET (PET0) fibers. The results of microstructure investigations suggested that the amorphous orientation factor of PETS fibers is higher than that of PET0 fibers. It is suggested that the increase of amorphous orientation factor contributed to the improvement of tensile properties of PET fibers. Considering the difference in modulus-strain curves of PET0 and PETS fibers, it is believed that the addition of nanoparticles not only improved the amorphous orientation factor but also changed the load units of PET fibers when strained, which also resulted in the improvement of tensile properties.