tank containing the aromatic alcohol as shown above is allowed to cool to 70 u00b0 c and fourteen 14 pounds of diethanolamine 99 are slowly added while the temperature is kept under 90 u00b0 c after all the diethanolamine has been added forty three 43 pounds of tetrabromophtalic anhydride are added and the temperature is maintained at approximately 140 u00b0 c until the reaction is complete thirty minutes has been found to provide sufficient time for the reaction to complete itself at 140 u00b0 c as shown in the following equation str2 the brominated flame retardant produced is a clear viscous liquid with only slight water solubility other polyhydroxy compounds can be used in place of ethylene glycol to form suitable derivatives for reaction with the tetrabromophthalic anhydride to form flame retardants as shown in the equation below str3 examples of other reactive compounds which may be used in place of ethylene glycol are as follows propylene glycol polyethylene glycol ethylene oxide propylene oxide compounds of general formula roh where r is any alkyl or substituted alkyl group the group may be primary secondary or tertiary it may be an open chain or cyclic and it may contain a double bond a halogenated or aromatic ring the brominated flame retardants produced as shown above are only slightly soluble or insoluble in water but can be made more soluble by adding for example ammonium hydroxide nh 4 oh in the amount of 3 7 of the flame retardant 39 s weight directly to the flame retardant also the ammonium hydroxide can be added instead to the finishing bath during fabric processing if desired other water soluble basic compounds may be used to raise the ph of the flame retardant solution such.