Abstract: Zine stannate (Zn2SnO4) was synthesized through twostep calcining from SnCl4 and Zn(NO3)2, and was used as a flameretardant/smoke suppressant for flexible poly (vinyl chloride). The flame retardacy was characterized by the limited oxygen index test, smoke density test (SDR), and the char yield test. The mechanical properties were also studied. When 15 phr Zn2SnO4 was used, PVC showed excellent flame retardacy and smoke suppression, limited oxygen index was 36.0 %, SDR was 86.2 %, char yield was 29.7 %, tensile strength was 25.47 MPa, and elongation at break was 168 %. Differential thermal analysis, thermogravimetry, and scanning electron microscope showed that Zn2SnO4 decreased the degradation temperature and increased char yield.

Key words: flame retardant, poly (vinyl chloride), Zn2SnO4, smoke suppression, thermal analysis