Study on Flame Retardancy and Mechanical Properties of PVC Composites for Wires and Cables.

In order to improve the flame retardancy of polyvinyl chloride (PVC) used for wires and cables, zinc borate (ZB) was added to PVC to prepare PVC composites, and its flame retardancy and mechanical properties were studied. The mechanical properties test showed that with the increase of ZB content, the tensile properties of PVC composites decrease dgradually. However, when the ZB content was less than 6%, the tensile properties of PVC composites decreased slightly, which still met the requirements of relevant standards. The flame retardant test showed that the flame retardant of PVC composites increased with the increase of ZB content. When the content of ZB was 6%, the comprehensive properties of PVC composite (4#) were excellent. Compared with the composite without ZB, the flame retardancy of the 4# sample was significantly improved, the oxygen index reached 40.1%, the vertical combustion grade reached FV-0, the smoke density decreased to 72, the HCl release decreased to 41 mg/g, the peak heat release rate (PHRR) was decrease by 19.9%, the total heat release (THR) was decreased by 36.5%, and the total smoke production (TSP600 s) was decreased by 69.7%. The tensile strength of the composite was decreased by 10.8%, and the elongation at break was decreased by 12.7%. [ABSTRACT FROM AUTHOR]