Study on Morphology, Rheology, and Mechanical Properties of Poly(trimethylene terephthalate)/CaCO3 Nanocomposites

Abstract

For preparing good performance polymer materials, poly(trimethylene terephthalate)/CaCO3 nanocomposites were prepared and their morphology, rheological behavior, mechanical properties, heat distortion, and crystallization behaviors were investigated by transmission electron microscopy, capillary rheometer, universal testing machine, impact tester, heat distortion temperature tester, and differential scanning calorimetry (DSC), respectively. The results suggest that the nano-CaCO3 particles are dispersed uniformly in the polymer matrix. PTT/CaCO3 nanocomposites are pseudoplastic fluids, and the CaCO3 nanoparticles serve as a lubricant by decreasing the apparent viscosity of the nanocomposites; however, both the apparent viscosity and the pseudoplasticity of the nanocomposites increase with increasing CaCO3 contents. The nanoparticles also have nucleation effects on PTT’s crystallization by increasing the crystallization rate and temperature; however, excessive nanoparticles will depress this effect because of the agglomeration of the particles. The mechanical properties suggest that the CaCO3 nanoparticles have good effects on improving the impact strength and tensile strength with proper content of fillers. The nanofillers can greatly increase the heat distortion property of the nanocomposites.