Microstructure, thermal stability, and mechanical properties of modified polycarbonate with polyolefin and silica nanoparticles

Abstract

In this manuscript, the supramolecular structure and dynamic mechanical thermal behavior of the polycarbonate (PC)/ethylene propylene copolymer (EPC)/silica (SiO2) nanocomposites (NCs) have been studied. The morphological analysis of the fractured Izod impact surfaces revealed the mechanism of energy absorption for the elastomeric particle in front of the crack growth. The cracks growth and deformation of voids around the EPC phase are the main factors for energy absorption during the notched‐Izod impact test. The presence of the SiO2 nanoparticles (NPs) in the PC phase causes the increase in the values of the impact strength for the NCs specimens. No new peaks and bonds were observed in the Fourier transform infrared (FTIR) spectra, and consequently, the phase behavior of the PC/EPC blends did not change significantly upon SiO2 addition. The dynamic mechanical thermal analysis result confirms the existence of two glass transitions temperatures and independence of all components in the system. Examination of the interfacial studies revealed that the SiO2 NPs do not exist at the interface of PC and EPC. In addition, applying SiO2 NPs into the blends improved the storage modulus (E′) and thermal stability of the PC/EPC/SiO2 NCs. Copyright © 2017 John Wiley & Sons, Ltd.