The effect of calcium carbonate on the performance of PVC waterproofing membrane
PVC waterproofing membrane was prepared using calcium carbonate filled and modified with dioctyl phthalate (DOP), and the effects of DOP, light calcium carbonate (PCC) and heavy calcium carbonate (GCC) on the mechanical properties, processing properties and microstructure of PVC waterproofing membrane were studied. The results show that: with the increase in DOP content, PVC waterproofing membrane tensile strength and tear strength decreased, elongation at break increased, processing performance was greatly improved. In the case of a certain amount of calcium carbonate, the mechanical properties of the GCC-filled system is better than the PCC-filled system, but the processing properties are slightly worse. When the DOP content was 50 parts and the GCC content was 2030 parts, the processing process was easy and the tensile strength was the largest at 14.58 MPa and the tear strength was the largest at 69.15 N/mm, which ensured that the system had excellent mechanical properties with better processing performance. It was found by scanning electron microscopy that with the increase of DOP content, the interface became more flat and smooth, and the compatibility between them was better; in the case of 20 parts of calcium carbonate, the interface of heavy calcium system was blurred and flat and smooth, and the compatibility was better, while the interface of light calcium system was relatively clear and rough, and the compatibility was poor.
