The present invention discloses a preparation method of an insulating dielectric for improving energy density, including dissolving 1,4-phenylene diisothiocyanate in a polar solvent, then adding an organic diamine, and reacting at room temperature for 3 h to 6 h under a nitrogen atmosphere; then adding 4,4′-oxydianiline and pyromellitic dianhydride, and reacting at room temperature for 12 h to 18 h under a nitrogen atmosphere to obtain a random copolymer solution of polythiourea and polyamic acid; and spreading the random copolymer solution of polythiourea and polyamic acid on a copper plate, and carrying out gradient temperature elevation to obtain a random copolymer of polythiourea and polyimide.

There are provided a carbodiimide compound excellent in storage stability, and performance as a crosslinking agent, and a method for producing the same, and a resin composition excellent in the film forming properties and solvent resistance of a coating made at low temperature. A polycarbodiimide compound derived from an aliphatic diisocyanate compound having at least one primary isocyanate group, the polycarbodiimide compound having a structure in which all ends are capped with an organic compound having a functional group that reacts with an isocyanate group, carbodiimide group concentration A (%) and weight average molecular weight Mw satisfying the following formula (1), and a resin composition comprising the carbodiimide compound and an aqueous resin having a predetermined acid value at a predetermined ratio.

(A/Mw)×1000≥0.55  (1)

A method for producing a porous material includes processing a urethane resin composition containing a urethane resin (A) and a solvent (B) by a wet film forming process, in which the solvent (B) satisfies the following conditions: a difference between a Hansen solubility parameter of the solvent (B) (B-HSP) and a Hansen solubility parameter of the urethane resin (A) (A-HSP) is in the range of 3 to 8 (J/cm.sup.3).sup.1/2 and a difference between the Hansen solubility parameter of the solvent (B) (B-HSP) and a Hansen solubility parameter of water (W-HSP) is in the range of 31.5 to 38 (J/cm.sup.3).sup.1/2. The Hansen solubility parameter of the solvent (B) preferably has a dispersion term (δD) in the range of 15.5 to 21.0 MPa.sup.0.5, a polar term (δP) in the range of 7.0 to 14.5 MPa.sup.0.5, and a hydrogen bond term (δH) in the range of 4.5 to 11.0 MPa.sup.0.5.

To provide: a solvent used for synthesizing a synthetic resin such as a polyimide resin and a polyurethane resin, the solvent capable of synthesizing a polymer having a high molecular weight in a short time, causing no clouding of a reaction solution during and after reaction, and having high transparency and storage stability; and a method for producing the synthetic resin using the solvent. A solvent (C) for resin synthesis, containing: 10 to 99.9999 mass % of an amide-based solvent (A); and 0.0001 to 5 mass % of a reaction accelerator (B), in which the reaction accelerator (B) is an aliphatic or aromatic tertiary amine compound having one or more tertiary amino groups in a molecule of the reaction accelerator (B).

A liquid composition comprising (a) a solvent or solvent mixture containing at least 50% by weight, based on the total amount of solvents, of a dioxabicycloalkane derivative, (b) an aromatic tricarboxylic acid anhydride, and (c) an aromatic diisocyanate,
can be used as coating composition for metal surfaces.

A method forming a surface modifying composition with reduced need for organic solvent and evaporation thereof for removal of insoluble reaction byproducts from the composition. The purified composition can be used in the formation of articles having improved biocompatibility, such as medical articles (e.g., spun hollow fiber).

The present invention discloses a preparation method of an insulating dielectric for improving energy density, including dissolving 1,4-phenylene diisothiocyanate in a polar solvent, then adding an organic diamine, and reacting at room temperature for 3 h to 6 h under a nitrogen atmosphere; then adding 4,4-oxydianiline and pyromellitic dianhydride, and reacting at room temperature for 12 h to 18 h under a nitrogen atmosphere to obtain a random copolymer solution of polythiourea and polyamic acid; and spreading the random copolymer solution of polythiourea and polyamic acid on a copper plate, and carrying out gradient temperature elevation to obtain a random copolymer of polythiourea and polyimide.

A cross-linkable composition can be provided in the present application. In one embodiment, the cross-linkable composition can allow a membrane formed of the cross-linkable composition to have an excellent interfacial adhesion with another membrane and prevent the occurrence of a detachment phenomenon or the like.

A conductive composition for conductive coatings, gap fillers, caulks and fairing compounds that are useful for EMI shielding, electrical grounding, lightning strike protection, and reduced radar cross-section for low observability (LO), with improved resistance to exposure to water, oil and other fluids contains at least one aspartic ester, at least one isocyanate and a conductive filler.

The disclosure relates to a thermoset omniphobic composition, which includes a thermoset polymer with first, second, and third backbone segments, first urethane groups linking the first and third backbone segments, and second urethane groups linking the first and second backbone segments. The first, second, and third backbone segments generally correspond to urethane reaction products of polyisocyanate(s), hydroxy-functional hydrophobic polymer(s), and polyol(s), respectively. The thermoset omniphobic composition has favorable omniphobic properties, for example as characterized by water and/or oil contact and/or sliding angles. The thermoset omniphobic composition can be used as a coating on any of a variety of substrates to provide omniphobic properties to a surface of the substrate. Such omniphobic coatings can be scratch-resistant, ink/paint resistant, dirt-repellent, and optically clear. The thermoset omniphobic composition can be applied by different coating methods including cast, spin, roll, spray and dip coating methods.