Ultra white N,N'-bis(tetrabromophthalimide) and its production in aqueous acetic acid
AssigneeGreat Lakes Chemical Corporation
InventorsBrian Tarbit, Brian Adger, Paul Willett
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Abstract
Disclosed is a process for producing an ultra-white N,N'-ethylene-bis(tetrabromophthalimide) product useful as a flame retardant. Also disclosed is a flame retardant composition predominantly comprised of N,N'-ethylene-bis(tetrabromophthalimide) and having unprecedented color and high purity.
Claims14
A flame retardant composition at least about 95% by weight comprised of N,N'-ethylene-bis(tetrabromophthalimide) having a yellowness index of 5 or less and 1% or less weight loss in thermogravimetric analysis to 400.degree. C.
A flame retardant composition which is produced by a process which comprises:
- (a) slurrying tetrabromophthalic anhydride into aqueous acetic acid;
- (b) adding ethylene diamine to the slurry thus obtained to achieve essentially a 1:2 molar ratio of ethylene diamine to tetrabromophthalic anhydride, said adding occurring with the slurry at a temperature of at least about 80.degree. C.;
- (c) reacting the product of step (b) at a temperature of at least about 120.degree. C.;
- and
- (d) drying the product of step (c);
- so as to form a white product at least 95% comprised of N,N'-ethylene-bis(tetrabromophthalimide), said product further being characterized by having a yellowness index less than 5 and a weight loss of 1% or less in thermogravimetric analysis to 400.degree. C.
Dependencies are inferred from the claim text.