Effect of Modifying Agent (ACR) on Cell Structure and Mechanical Properties of Extrusion-Foamed PVC Sheet

Rigid polyvinyl chloride (R-PVC) foam sheets were prepared in a continuous extrusion foaming system by using supercritical CO2 as the foaming agent. The effects of acrylic resin (ACR) on the rheological properties of PVC were investigated using a Brabender torque rheometer while other basic formula remained unchanged. The influences of ACR content on microstructure, and mechanical properties of PVC foamed sheet were investigated. The rheological test results showed that with the addition of ACR, the gelation time of the formula was gradually shortened while the equilibrium torque increased. With the increase of ACR content in the formula, the tensile strength, elongation at break, flexural strength and notched impact strength of PVC increased initially and then decreased, implying that there exists an optimum ACR content for improving the mechanical properties of foamed PVC sheet.