Phosphorus-containing imide resins
AssigneeThe United States of America as represented by the Administrator of the National Aeronautics and Space Administration
InventorsIndra K. Varma, George M. Fohlen, John A. Parker
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Abstract
Bis- and tris-imides derived from tris(m-aminophenyl) phosphine oxides by reaction with maleic anhydride or its derivatives, and addition polymers of such imides, including a variant in which a mono-imide is condensed with a dianhydride and the product is treated with a further quantity of maleic anhydride. Such monomers or their oligomers may be used to impregnate fibers and fabrics which when cured, are flame resistant. Also an improved method of producing tris(m-aminophenyl) phosphine oxides from the nitro analogues by reduction with hydrazine hydrate using palladized charcoal or Raney nickel as the catalyst.
Claims8
Imides having the structure ##STR6## wherein R.sub.1 and R.sub.2 are selected from the class consisting of chloro, lower alkyls and hydrogen and R.sub.3 is the amino group or an imide group ##STR7##
Monomers having the structure ##STR8## wherein R.sub.1 and R.sub.2 are selected from the class consisting of hydrogen chloro, and lower alkyls, R.sub.3 is --NH.sub.2 or the imide group ##STR9## and wherein X is a linking entity selected from the class consisting of a valence bond, --O--, --S--, --C.sub.n H.sub.2n -- wherein n is 1, 2 or 3, ##STR10## and --SO.sub.2 --.
Dependencies are inferred from the claim text.