摘要:
Methods of making low density modified polyimide! polyimide-amide foams and the resulting compositions. An N-substituted aliphatic imide is prepared by reacting a suitable aromatic dianhydride with a suitable oxime. A polyimide forming material is prepared by dissolving the N-substituted aliphatic imide in an esterifying solvent, then adding a suitable aromatic diamine. This material is dried to a powder. A suitable hydrated compound which is stable up to at least about 100°C. is mixed with the powder. A foam is then produced by heating the material to reaction temperature for a period sufficient to produce a stable foam. The material melts, then spontaneously expands into a foam which becomes self supporting and cures to a resilient flexible foam. The addition of the hydrated compound is found to result in an exceptionally low density foam. Depending upon heating conditions, a polyimide, polyimide- amide or mixture thereof may be produced, resulting in foams having selectively variable physical properties.
摘要:
A method of making a bisimide coating composition comprises: (a) mixing at least one lactam and/or amino acid (component A) with at least one dianhydride (component B) in a mole ratio of A:B of from 0.01:1 to 10:1 to form an N,N'-disubstituted bisimide dicarboxylic acid, (b) dissolving the product from step (a) in a water-miscible solvent, (c) mixing water with the solution from step (b) to form a solution comprising from 10% to 80% by weight of water, (d) mixing at least one aromatic diamine (component C) with the solution from step (c), and (e) mixing at least one tertiary amine (component D), in an amount of from 2% to 20% by weight based on the water added in step (c), with the solution from step (d) to give the coating composition.
摘要:
A method of making a bisimide coating composition comprises:
(a) mixing at least one lactam and/or amino acid (component A) with at least one dianhydride (component B) in a mole ratio of A:B of from 0.01:1 to 10:1 to form an N,N'-disubstituted bisimide dicarboxylic acid, (b) dissolving the product from step (a) in a water-miscible solvent, (c) mixing water with the solution from step (b) to form a solution comprising from 10% to 80% by weight of water, (d) mixing at least one aromatic diamine (component C) with the solution from step (c), and (e) mixing at least one tertiary amine (component D), in an amount of from 2% to 20% by weight based on the water added in step (c), with the solution from step (d) to give the coating composition.
摘要:
A method of making a resilient, flame resistant, non-friable polyimide foam comprises:
(a) mixing at least one aromatic dianhydride with an alcohol and heating the resulting mixture to form a half-ester, (b) mixing a diamine component comprising at least one aliphatic diamine and at least one aromatic diamine with the product from step (a), (c) drying the resulting mixture, and (d) heating the resulting solid to give a polyimide foam.
摘要:
Modified polyimide coatings and adhesives useful for high efficiency bonding at moderate temperatures. Basically, the coatings and adhesives are prepared by reacting suitable quantities of an oxime, and one or more aromatic tetracarboxylic acid dianhydrides, dissolving or esterifying the resulting bisimide with a reactive solvent esterifying agent and mixing therewith a suitable diamine. This polyimide may be dried to a selected viscosity before or after coating onto one or both surfaces to be bonded together. When the surfaces are heated for a suitable period at a temperature in the range or about 230 to 320 °C an excellent, flexible coating is obtained, or when coated surfaces are pressed together under moderate pressure a high peel strength bond with excellent resistance to high temperatures results.
摘要:
Terpolyimides are prepared from tetracarboxylic acid esters and combinations of heterocyclic, aromatic, and aliphatic diamines. Precursors, and methods of converting them to the corresponding terpolymers are described. The terpolyimides are useful as foams.