Abstract: This invention provides methods for producing a high-molecular weight polycarbodiimide solution from an organic diisocyanate in the presence of a carbodiimidation catalyst, wherein 1) a chlorinated aliphatic hydrocarbon or 2) an alicyclic ether is used as a solvent. This invention also provides a polycarbodiimide solution with excellent stability in preservation.

Abstract: The present invention provides a melamine resin foam comprising a foam body obtained by foaming a resin composition composed mainly of a melamine-formaldehyde condensate and a blowing agent, and hydrophobic component coated on said foam body.This melamine resin foam is improved in fragility and water absorbability and in which the drawbacks of the prior art have been alleviated.

Abstract: The present invention provides a process for producing a polycarbodiimide resin from an aliphatic diisocyanate and a terminal-blocking agent in the presence of a carbodiimidization catalyst, wherein the aliphatic diisocyanate is tetramethylxylylene diisocyanate represented by the following formula ##STR1## and polymerization is conducted using no solvent. The polycarbodiimide resin obtained by the above process has good storage stability and excellent miscibility with organic solvents.

Abstract: The present invention provides a tetramethylxylylene carbodiimide represented by the following formula ##STR1## wherein R is a monoisocyanate residue and n represents an integer of 1 or more. Said carbodiimide has good storage stability owing to reduced reactivity and gives good handleability in a reaction with an active hydrogen compound.

Abstract: A process for producing a high-molecular weight polycarbodiimide solution by subjecting isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, tetramethylxylylene diisocyanate or a mixture thereof to decarboxylation and condensation reaction in the presence of a carbodiimidization catalyst, in which process tetrachloroethylene, trichloroethylene, tetrachloroethane, trichloroethane or a mixture thereof is used as the polymerization solvent, the monomer concentration is 18% by weight or less, and the reaction temperature is 80.degree. C. or above.

Abstract: The present invention relates to a thermosetting resin having high thermal resistance, high strength, flame resistance, and good processability which can be obtained by reacting polycarbodiimide substantially produced from one or more kinds of organic polyisocyanate with crosslinking agents having two or more active hydrogen groups in their molecules, one or more kinds of compounds having epoxy groups in their molecules or compounds capable of accelerating the trimerization reaction of carbodiimide, and production methods thereof.

Abstract: A stampable sheet shaped-product has a skin layer consisting essentially of a foamable thermosetting resin and formed on and in one or both of surfaces of a sheet-like open cell plastic foam. Optionally, a facing material layer of a proper material may be formed on one or both of surfaces of the skin layer. Such stampable sheet shaped-product is produced by applying a composition consisting essentially of a foamable thermosetting resin onto one or both of surfaces of a sheet-like open cell plastic foam, so that the one or both surfaces is or are impregnated with the composition. Optionally, a proper facing material is placed on one or both of the surfaces, and the resulting material is subjected to a hot pressing. Alternatively, the stampable sheet shaped-product may be produced by a process including a thermal treatment step interposed between the above-described applying and hot-pressing steps.

Abstract: A thin carbon plate obtained by forming a polycarbodiimide resin or a mixture of a polycarbodiimide resin and polycarbodiimide fibers into a thin plate and carbonizing the thin plate. This thin carbon plate is suitable for use as a fuel cell separator.

Abstract: The present invention relates to a thermosetting resin having high thermal resistance, high strength, flame resistance, and good processability which can be obtained by reacting polycarbodiimide substantially produced form one or more kinds of organic polyisocyanate with crosslinking agents having two or more active hydrogen groups in their molecules, one or more kinds of compounds having epoxy groups in their molecules or compounds capable of accelerating the trimerization reaction of carbodiimide, and production methods thereof.

Abstract: A process for producing a parabanic acid ring-containing polymer, which comprises reacting a polycarbodiimide polymer with oxalyl chloride and then treating the reaction product with water.