Binary mixtures of metal compounds as flame retardants for organic polymers

✍ Scribed by F.K. Antia; C.F. Cullis; M.M. Hirschler

• Publisher: Elsevier Science
• Year: 1982
• Tongue: English
• Weight: 591 KB
• Volume: 18
• Category: Article
• ISSN: 0014-3057
• DOI: 10.1016/0014-3057(82)90185-9

✦ Synopsis

Studies have been made of the effect on the flammability of thermoplastic polymers of the partial or total replacement of one metal compound by another in the presence also of a suitable halogen compound: particular attention has been paid to systems where the primary flame retardant is antimony(Ill) oxide. With each binary metal compound system investigated, ten different compositions have been chosen so as to provide a symmetrical arrangement of points within a triangular design: resulting calculated values of the limiting oxygen index for each polymer flame retardant system for a given polymer are shown as a graphical contour analysis. Comprehensive studies of several systems show that both iron(Ill) oxide and aluminium oxide monohydrate can significantly enhance the flameretardant action of antimony(Ill) oxide but that several other metal compounds, although not as effective as Sb203, may nevertheless be used as adequate partial replacements for it. The Fe203-SnO:. H20 system can also act as an effective flame retardant under certain conditions. The SnO-ZnO system perhaps best illustrates the importance of the polymer substrate and of the total additive loading as factors controlling the flame-retardant effectiveness. For all the systems studied, however, ABS is a much better substrate than HDPE, The results of a reasonably detailed study of the flame retardance conferred by several different compositions of a binary metal compound mixture give a much more reliable indication of the effects on polymer flammability of the constituent metal compounds than are obtained simply by replacement of a given concentration of one compound by another.