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Lee, Raymond

Publications and source records attributed to Lee, Raymond.

23 records · Page 2

Polyimide foams

Copolymide foams derived from a diester of 3,3',4,4'-benzophenonetetracarboxylic acid, an aromatic diamine, and a heterocyclic diamine. A molar concentration of the heterocyclic diamine approaching but not exceeding 0.42 is employed. This results in a flexible foam with a homogeneous cellular structure and a reduced compression set loss.

Gagliani, John↗

Polyimides

Terpolyimides prepared from tetracarboxylic acid esters and combinations of heterocyclic, aromatic, and aliphatic diamines and artifacts composed of those terpolymers. Precursors, and methods of converting them to the corresponding terpolymers.

Gagliani, John↗

Polyimides

Terpolyimides prepared from tetracarboxylic acid esters and combinations of heterocyclic, aromatic, and aliphatic diamines and artifacts composed of those terpolymers. Precursors, and methods of converting them to the corresponding terpolymers.

Gagliani, John↗

Polyimides

Terpolyimides prepared from tetracarboxylic acid esters and combinations of heterocyclic, aromatic, and aliphatic diamines and artifacts composed of those terpolymers. Precursors, and methods of converting them to the corresponding terpolymers.

Gagliani, John↗

Methods of preparing polyimides and artifacts composed thereof

Methods of converting essentially unpolymerized precursors into polyimides in which the precursors are exposed to microwave radiation. Preheating, thermal post-curing, and other techniques may be employed to promote the development of optimum properties; and reinforcements can be employed to impart strength and rigidity to the final product. Also disclosed are processes for making various composite artifacts in which non-polymeric precursors are converted to polyimides by using the techniques described above.

Gagliani, John↗