Abstract: A complex crystal is composed of anion of triiodine and cation of a fused compound consisting essentially of at least one nitrogen atom and at least 3 aromatic fused rings. Since the complex crystal has such a stable structure, it shows excellent heat resistance and excellent moisture resisting property. Furthermore, the complex crystal has light-polarizing performance because of an arrangement of the molecular chain of iodine. Moreover, the complex crystal exhibits excellent polarization because of an interaction between the fused compound and iodine. Therefore, the complex crystal is suitable for use as light-adjusting particles of a light valve or a light-adjusting glass.

Abstract: A complex crystal is composed of anion of triiodine and cation of a fused compound consisting essentially of at least one nitrogen atom and at least 3 aromatic fused rings. Since the complex crystal has such a stable structure, it shows excellent heat resistance and excellent moisture resisting property. Furthermore, the complex crystal has light-polarizing performance because of an arrangement of the molecular chain of iodine. Moreover, the complex crystal exhibits excellent polarization because of an interaction between the fused compound and iodine. Therefore, the complex crystal is suitable for use as light-adjusting particles of a light valve or a light-adjusting glass.

Abstract: A method for detecting stresses includes the steps of dispersing a fluorescent substance in a solid portion where stresses are to be detected, measuring fluorescence decay time of the fluorescent substance dispersed in the solid portion, and detecting stresses in the solid portion based on the measured fluorescence decay time. The method enables to non-destructively detect stresses in resin-molded products without impairing their mechanical properties.

Abstract: A variable-modulus material is composed of a polymer whose constituent unit is a thiophene or pyrrole molecule having from one to three C.sub.4-12 alkyl side chains, or a copolymer whose constituent unit is the thiophene or pyrrole molecule and which includes in a main chain thereof a conjugated compound with a K-electron bond directly bonded to the above molecule, and at least one additive (in an amount of 0.5-20 wt % of said polymer) selected from halogens, protonic acids, and transition metal halides. It greatly decreases in modulus upon application of an electric field as low as 5-150 V/mm and restores its original modulus upon removal of the electric field. It is suitable for use as vibration dampers and shock absorbers.

Abstract: A material with variable viscoelasticity is composed of an electrically insulating polymeric material, and fine particles dispersed therein and capable of electric polarization under an applied electric field. The particles may, for example, be of a conjugated and unsaturated organic compound, a polyelectrolyte, or an organometallic complex salt. The material is capable of a reversible change of viscoelasticity depending on the intensity of the applied electric field.

Abstract: Star-shaped nylons with low melt viscosities and excellent mechanical properties, methods for their preparation, a novel tetrasubstituted carboxylic acid for use as a polymerization core therefor and methods for its preparation are provided.A star-shaped nylon has polymer chains emanating from 3 or more polymerization initiation groups which are substituents bonded to every other or more separated carbon atoms on an aromatic ring of an aromatic compound. The star-shaped nylon is produced by homogeneously mixing the aromatic compound with molten nylon monomer and polymerizing the nylon monomer with the respective polymerization initiation groups as the starting points. A novel tetrasubstituted carboxylic acid having a structure of 3,5,3',5'-biphenyltetracarboxylic acid is useful as a polymerization core for star-shaped nylons.

Abstract: Disclosed herein is a polyimide composite material which comprises a polyimide-containing resin and a layered clay mineral which is intercalated with organic onium ions and dispersed in the polyimide. Owing to the intercalated clay mineral, the composite material has improved gas and water vapor barrier properties and a small thermal expansion coefficient. Disclosed also herein is a process for producing a polyimide composite material which comprises the steps of intercalating a layered clay mineral with organic onium ions, adding by mixing the intercalated clay mineral to a solution of a monomer or prepolymer for polyimide, removing the solvent, and forming a polyimide. This process makes the layered clay mineral miscible with and dispersible in polyimide.

Abstract: A fiber reinforced plastics comprises a resin and chopped strands dispersed in the resin, wherein the chopped strands comprise glass fiber chopped strands composed of cut assemblies of glass filaments and high elastic chopped strands composed of cut assemblies of high modulus inorgtanic filaments having higher elastic modulus than the filaments and having 3000 or less number of assembled filaments. By this arrangement, the both chopped strands are closely and uniformly dispersed in the resin and the force interaction between the both chopped stands are enhanced. The resultant plastics has remarkably improved strength and fatigue durability, and higher rigidity than conventional ones.

Abstract: Provided herein is a composite material which comprises a polyamide-containing resin, a layered silicate dispersed therein, and a substance such as polyamine which controls the crystalline structure or molecular structure of the resin. The composite material has improved mechanical strength and toughness and high clarity or transparency.

Abstract: A composite material comprising a resin other than polyamide resin and a layered silicate dispersed therein, said layered silicate having a layer thickness of 7 to 12 .ANG. and an interlayer distance of 30 .ANG. or above. Owing to the layered silicate uniformly dispersed in the resin matrix, the composite material is superior in mechanical characteristics and heat resistance. It also has good water resistance and chemical resistance.

Abstract: Composite material with high mechanical strength and excellent high-temperature characteristics comprising a polymer matrix containing polyamide and layers of a silicate uniformly dispersed in the order of molecules in the polymer matrix, each of said silicate layers being 7 to 12 .ANG. thick and the interlayer distance being at least 20 .ANG.; and a process for manufacturing such composite material.

Abstract: A reinforced thermoplastic resin composition comprising a thermoplastic resin, a fibrous, flaky or powdery inorganic reinforcing material, and an uncured, thermally curable resin, such as a thermosetting resin, applied to the surfaces of the inorganic reinforcing material. Molding of this composition by injection molding or the like yields a molded product in which the thermally curable resin has been cured by the heat during the molding to provide a strong chemical bond between the inorganic reinforcing material and the thermoplastic resin. The molded product thus obtained possesses more strength and/or elongation than the conventional thermoplastic resin product.

Abstract: Composite material with high mechanical strength and excellent high-temperature characteristics comprising a polymer matrix containing polyamide and layers of a silicate uniformly dispersed in the order of molecules in the polymer matrix, each of said silicate layers being 7 to 12 Å thick and the interlayer distance being at least 20 Å; and a process for manufacturing such composite material.