Metal hydroxystannates as flame retardants and smoke suppressants for semirigid poly(vinyl chloride)

Abstract

Metal hydroxystannates were studied as flame retardants and smoke suppressants for semirigid poly(vinyl chloride) (PVC). The flame-retardant and smoke-suppression mechanisms were investigated by using limiting oxygen index (LOI), smoke density rating (SDR), the solid yield test (SY), scanning electron microscopy (SEM), thermogravimetry, differential thermogravimetry, and differential thermal analysis. Results showed that semirigid PVC treated with the flame retardants had a higher LOI, and solid yield, but a lower SDR and maximum smoke density, thereby indicating that the flameretardance and smoke-suppression properties of the treated PVC were improved and that the hydroxystannate compounds could be used as highly effective flame retardants. The tin compounds may exert their action in both the condensed and vapor phases, but mainly in the condensed phase as Lewis acids. a LOI ¼ limiting oxygen index, SDR ¼ smoke density rating, MSD ¼ maximum smoke density, SY ¼ solid yield, EFF ¼ flame retardant efficiency. heated at temperatures ranging from 200 to 3008C, thereby producing water and ZnSnO 3 in an endothermic process. The weight loss (water) of ZHS is 18.9%, and this result is in accordance with the calculated one (the water content is 19.3%). The data indicate that the original product was ZHS.Samples were prepared by mixing PVC with DOP, heat stabilizer, lubricant, and various flame retardants, FIG. 3. TG, DTG, and DTA curves of the PVC samples (at a heating rate of 208C min 21 ). a TM 1 ¼ temperature at the maximum velocity of the first stage, MV 1 ¼ maximum velocity of the weight loss in the first stage, TM 2 ¼ temperature at the maximum velocity of the second stage, MV 2 ¼ maximum velocity of the weight loss in the second stage.

A novel intumescent flame retardant and smoke suppression system for flexible PVC

“…Figure 3c shows that the decomposition temperature of MAZSN is lower than that of MA, which is because the decomposition temperature of the ZHS contained in MAZSN is 220°C 19. Between 227 and 350°C, the dehydration reaction of ZHS overlaps with the sublimation reaction of MA, so a distinct endothermic peak appears at 265°C in the DTA curve.…”

Synthesis of a Solid Superacid and Its Application in Flame-Retardant Poly(vinyl chloride) Material

“…The HCl released is an effective gas phase flame inhibitor, and PVC molecules are highly crossl-inked to form carbon films, which play the role of heat insulation and oxygen insulation. 32 The process is demonstrated with TiO 2 in Figure 10.…”

“…The TiCl 4 alkylates with another PVC molecule, and it gives off HCl so as to cause an autocatalytic reaction. The HCl released is an effective gas phase flame inhibitor, and PVC molecules are highly crossl-inked to form carbon films, which play the role of heat insulation and oxygen insulation . The process is demonstrated with TiO 2 in Figure .…”

An Overview of the Flame Retardants for Poly(vinyl chloride): Recent States and Perspective†

“…Then a series of metal hydroxystannates including Mg, Sr, Cu, Co, Ni, Mn, Fe and Zn were added into PVC to compare the flame retardant efficiency by Xu et al . [ 52 ] Among these flame retardants, 2 phr Fe 2 Sn 3 (OH) 18 ‐treated PVC composite showed the highest LOI value as 37.5%, while LOI value of PVC containing 2 phr SrSn(OH) 6 was the lowest as 33.0%. The same research group also combined ZHS with other metal hydroxystannates (metal = Mg, Sr, Mn, Fe, Co, Ni and Cu) and found that ZHS+Fe 2 Sn 3 (OH) 18 showed the best performance.…”