Study On Flame Retardation Of Tin Compounds And Preparation Of Nanometer Zinc Sulfide

The technology of flame-retardant for polymers developed quickly. With more attention were paid to the biologic environment, smoke-less and halogen-free flame-retardant become the main area of flame-retardant study. Inorganic fire-retardant has no halogen, excellent heat-resistance property. It is physiological innocuity material, amity to environment, and the most importance is no second pollution when burning that means no emission of noxious and causticity gas. So inorganic fire-retardant become the hot research subject in fire-retardant field. New technology such as miniaturization and surface modification were adopted to improve flame retardation effect of inorganic fire-retardant. So the main work of us is to look for effective new flame-retardant system and indicate their mechanisms. This article was divided into three parts: The first chapter is introduction. It recommend the present condition and development of flame-retardant, and put forward the significance and aim of the study. In the second chapter flame-retardant and smoke-suppressant properties of inorganic tin compounds such as zinc hydroxystannate(ZHS) and zinc stannate(ZS) were studied compare with Al(OH)3, Mg(OH)2 and Sb2O3 through the limiting oxygen index (LOI) test and smoke density test. Their mechanisms were studied through the char yield test, SEM, quantitative analysis, TG-DTA analysis. The results showed that tin compounds such as ZHS and ZS could be used as a highly effective flame retardant for flexible PVC, and it appears that tin may exert its action in both the condensed and vapor phases, but mainly in condensed phases as a Lewis acid. In the third chapter, nanometer ZnS was prepared by two different method homogeneous precipitation method and in-situ polymerization method. The products'size, disperse and surface are different. The ZnS nano-powder were characterized by XRD, TEM and TG-DTA analysis. The results show that the proportion of organic and inorganic component( i.e. coated efficiency) in PMM coated ZnS is relatively larger, and it has smaller particle size, better dispersion and stability characters.