Structural wood panels with improved fire resistance
AssigneeThe United States of America as represented by the Administrator of the National Aeronautics and Space Administration
InventorPaul M. Sawko
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Abstract
Structural wood paneling or other molded wood compositions consisting of finely divided wood chips, flour, or strands are bound together and hot pressed with a modified novolac resin which is the cured product of a prepolymer made from an aralkyl ether or halide with a phenol and a hardening agent such as hexamethylene tetramine. The fire resistance of these articles is further improved by incorporating in the binder certain inorganic fillers, especially a mixture of ammonium oxalate and ammonium phosphate.
Claims7
Flame-resistant cellulosic composite which comprises finely divided wood particles bound together by about 10 to 33% on a weight basis, of a cured thermosetting resin made from a prepolymer prepared by the reaction of (1) an aralkylether of the general formula R'[--(CH.sub.2 OR)].sub.a, wherein R' is selected from the group consisting of divalent aromatic hydrocarbon radicals, trivalent aromatic hydrocarbonoxy radicals, R is an alkyl radical containing less than 6 carbon atoms, and a is equal to 2 or 3;
- with a molar excess of (2) a phenolic compound containing from 1 to 3 hydroxyl groups.
Dependencies are inferred from the claim text.