Performances of PVC filled with different kinds of calcium carbonate

Abstract：In order to investigate the effects of different kinds of calcium carbonate on performance of PVC/CaCO3 composite, a twin-screw extruder was used for extrusion and granulation, while an injection molding machine was used for model injection. The mechanical properties were tested by a universal testing machine and a simply supported beam impact testing machine. The microscopic morphology of fractured surface was observed by a SEM. The results show that the filling effects of nano-CaCO3 and coated CaCO3 are the best. The tensile strengths of PVC were increased by 19% and 17%, respectively. The non-notched impact strengths of PVC were increased by four times, which are 54. 05 kJ/m^2 and 51.67 kJ/m^2 , respectively. The notched impact strengths of PVC were increased by about three times, which are 28.94 kJ/m^2 and 22.59 kJ/m^2 , respectively. The filling effect of composite calcium is mediocre, and those of GCC and PCC are the worst. After being filled with many varieties of calcium carbonate, the flat outline of original PVC changed, nano-CaCO3 and coated CaCO3 formed many uneven and rounded surfaces, and GCC and PCC form more flaws and holes.