Study On Extrusion Moulding Of Mocro-Foaming PVC/Wood Flour Composite

This paper studied prescriptions for PVC/wood flour micro-foaming composites. A single-screw extruder was used to make PVC/wood flour micro-foaming composites. By changing ingredients and quantity, we analyzed main factors that affected microstructure and mechanical property of wood plastic composites. We wanted to get PVC/wood flour micro-foaming composites with high mechanical property, low density and cost. The paper reviewed development of wood plastic composite and several theories of mixing and dispersion, adsorption, interface connecting and foaming. And we made a summary of research hotspots and challenges at home and abroad. By thinking over existing equipment situations and testing conditions, we focused on effects of multiple foaming agents and other process agents on microstructure and mechanical property of composites, such as compatibilizer, multiple stabilizer, impact modifier, and namo-CaCO₃. PVC, dried wood flour, multiple foaming agents and other process agent were mixed well at first. Then the single-screw extruder extruded mixture. Finally, sample extruded were tested for mechanics performance and analyzed by scanning electron microscopy (SEM). Tensile test, shear test and impact test were employed to evaluate the adhesion between wood flour and PVC matrix. We studied the test data and distributing of wood flour and cell in SEM, analyzed the relationship between prescriptions, microstructure and mechanical property. We got the main effects on PVC/wood flour composite, and made propose on prescriptions, equipments and process. And we gave some advices of prescriptions and process of PVC/wood flour micro-foaming composites.