Water resistance and flexural properties of three nano-fillers reinforced corn straw/polyvinyl chloride composites

This paper reports an investigation into the effects of nano-silicon dioxide, nano-titanium dioxide and nano-aluminum oxide (nano-SiO2, nano-TiO2, and nano-Al2O3) on the water resistance and flexural properties of corn straw/polyvinyl chloride (PVC) composites under simulated soil accelerated aging conditions, and the reinforcing effect of three nano-fillers was compared. The results indicated that the addition of nano-fillers exhibited a positive effect on the water resistance and flexural resistance properties of corn straw/PVC composites, especially nano-SiO2. After 21 d of the simulated soil accelerated aging, the nano-SiO2 reinforced composites had relatively low water absorption and moisture absorption rates, and the similar enhancement effect was also found with flexural strength, flexural modulus and flexural creep resistance. The microstructure of nano-SiO2 reinforced composites showed no significant breakage or pullout of the fiber, and the voids and the micro-cracks cannot be found in SEM observation indicating stronger interfacial bonding strength, thus improving the water-resistance and flexural resistance properties.