Phosphorus Flame Retardants for Polymeric Materials from Gallic Acid and Other Naturally Occurring Multihydroxybenzoic Acids

Table 2

Thermal degradation of blends of phosphorous esters of gallic acid anilide with DGEBA epoxy.

Blend	Level of additive in blend (%)	Level of phosphorous in blend (%)	Decomposition onset temperature (°C)^a		Temperature of maximum decomposition rate (°C)		Decomposition residue (%)^b
			Nitrogen	Air	Nitrogen	Air	Nitrogen	Air
DGEBA epoxy	0	0	390	374	423	408	8	8
GA-DEP-E	7.5	1	342	349	370	371	22	4
GA-DEP-E	15.0	2	327	334	352	354	25	6
GA-DOPO-E	9.6	1	360	372	394	392	16	3
GA-DOPO-E	19.1	2	348	353	381	375	16	3

^aExtrapolated onset temperature from the derivative plot of mass/loss versus temperature. ^bPercentage of the initial sample mass.