High compressive strength of home waste and polyvinyl acetate composites containing silica nanoparticle filler

Simple mixing and hot pressing methods were used to make composites from home waste—in particular, paper and dry leaves—using polyvinyl acetate (PVAc) as an adhesive and silica nanoparticles as filler. The optimum composition for the strongest composites, in terms of compressive strength, had a mass ratio of silica nanoparticles/PVAc/(paper + dry leaves) of 3:80:280. With this mass ratio, a compressive strength of 68.50 MPa was obtained for samples prepared at a pressing temperature of 150°C, pressing pressure of 100 MPa, and pressing time of 20 min. The addition of silica nanoparticles increased the compressive strength by about 50%, compared with composites made without the addition of nanosilica (45.60 MPa). Higher compressive strength was obtained at a higher pressing pressure. At a pressing pressure of 120 MPa, pressing temperature of 150°C, and pressing time of 20 min, a compressive strength of 69.10 MPa was obtained. When the pressing time was increased to 45 min at a pressing pressure of 120 MPa, a compressive strength of 84.37 MPa was measured. A model was also proposed to explain the effects of pressing pressure and pressing time on compressive strength. The model predictions were in good agreement with the experimental data.