Self-assembled natural rubber/silica nanocomposites: Its preparation and characterization

A novel natural rubber/silica (NR/SiO(2)) nanocomposite is developed by combining self-assembly and latex-compounding techniques. The results show that the SiO(2) nanoparticles are homogenously distributed throughout NR matrix as nano-clusters with an average size ranged from 60 to 150 nm when the SiO(2) loading is less than 6.5 wt%. At low SiO(2) contents (⩽4.0 wt%), the NR latex (NRL) and SiO(2) particles are assembled as a core-shell structure by employing poly (diallyldimethylammonium chloride) (PDDA) as an inter-medium, and only primary aggregations of SiO(2) are observed. When more SiO(2) is loaded, secondary aggregations of SiO(2) nanoparticles are gradually generated, and the size of SiO(2) cluster dramatically increases. The thermal/thermooxidative resistance and mechanical properties of NR/SiO(2) nanocomposites are compared to the NR host. The nanocomposites, particularly when the SiO(2) nanoparticles are uniformly dispersed, possess significantly enhanced thermal resistance and mechanical properties, which are strongly depended on the morphology of nanocomposites. The NR/SiO(2) has great potential to manufacture medical protective products with high performances.