抄録
In this study, both silane coupling agent treated silica particles (STSP) and untreated silica particles (UTSP) were dispersed in polyethylene terephthalate (PET) and the properties of these composites were evaluated. The mechanical properties of these silica particle/PET composites were investigated by dynamic viscoelasticity and SEM observations. The storage modulus at 40°C (E′40) increased with concentration of silica particles. The E′40 of the UTSP/PET composites were larger than the corresponding values for the STSP/PET composites. These results were compared with theoretical values estimated from the Halpin-Tsai equations. These results showed that STSP/PET composites had few voids and aggregations of particles, which indicated that molecular interactions exist between STSP and PET. STSP dispersion in PET was random close packing. The glass transition temperature (Tg) of PET filled with STSP increased by about 5°C in comparison with neat PET independent of the concentration of STSP. On the other hand, for UTSP, which easily condenses in PET, Tg was not increased by the addition of UTSP.
