Figure 2.

Flame retardancy analysis of epoxy resins containing phosphorus flame retardants in terms of the FRI values as a function of UL-94 test results. Symbols are indicative of different types of phosphorus flame retardant used. Hollow symbols are indicative of fiber-incorporated composites with details earlier given in the bottom of Table 1 as a to l notes. The vertical variation in each category, i.e., V-0, V-1, V-2, and NR, is schematically representative of the amount of additive used. For example, among two data distinguished by different symbols having the same or very close FRI values (horizontal quantity) in a given category (e.g., V-1), which have different vertical quantity both revealed V-1 behavior in UL-94 test, but the upper was an FR used in more quantity in preparation of epoxy composites.