Role of Surface Active Agent on Dimensional Stability of HDPE/CaCO3 Nanocomposites

摘要

Dimensional stability is normally defined as the ability of a material to maintain its size and shape under various temperatures and stresses. The parameter, which is used to determine dimensional stability, is thermal -expansion coefficient. This work deals with the study of the dimensional stability and thermal stability of high-density polyethylene (HDPE) and its nanocomposites by the presence of different stearic acid (SA) content as a modifier of surface. To investigate the role of surfactant on dimensional stability of HDPE nanocomposite reinforced with nano-sized calcium carbonate (CaCO3), nano-sized calcium carbonates were coated with different SA content. Standard specimens of HDPE/10 vol % CaCO3 nanocomposite were performed using injection method. To study dimensional stability of HDPE/10vol% nanocomposites, dilatometry method was used. The results showed that addition of nano-sized CaCO3 caused the decrease of thermal expansion coefficient of HDPE. In addition, dimensional stability of HDPE/10 vol% CaCO3 improved due to increasing SA content. Also, addition of inorganic fillers and surfactant retarded the thermal oxidation of HDPE.