Dispersion Behavior of TiO2 Nanoparticles in LLDPE/LDPE/TiO2 Nanocomposites

Abstract Summary: TiO 2 nanoparticles were introduced into linear low‐density polyethylene (LLDPE)/low‐density polyethylene (LDPE) composite films in the form of master batch where TiO 2 was pre‐dispersed in LDPE by melt compounding. The dispersion behavior of TiO 2 nanoparticles was investigated by field‐emission scanning electron microscopy (FE‐SEM). The rheology results show that the viscosity of LDPE/TiO 2 master batch is lower than that of LLDPE/LDPE composites. Energy dispersive X‐ray spectrometer (EDS) composition distribution map indicates that TiO 2 nanoparticles were dispersed randomly in the master batch. Scanning electron microscopy (SEM) images show that LDPE/TiO 2 master batch is crushed into micron scale dispersed phases due to the shear stress during the blow‐forming process. Subsequently, TiO 2 nanoparticles in the dispersed phases are released into the ambient matrix and form a wide ring composed of monodispersed particles. The sizes of spherical crystals decrease due to the presence of TiO 2 nanoparticles in LLDPE/LDPE/TiO 2 nanocomposites. The transparency of LLDPE/LDPE/TiO 2 composite films decreases little compared to that of LLDPE/LDPE composite films. SEM image of TiO 2 nanoparticles dispersed randomly in LLDPE/LDPE/TiO 2 composite films. magnified image SEM image of TiO 2 nanoparticles dispersed randomly in LLDPE/LDPE/TiO 2 composite films.