A method of making polyetherimide comprising reacting a first diamine having four bonds between the amine groups, a second diamine having greater than or equal to five bonds between the amine groups, 4-halophthalic anhydride and 3-halophthalic in the presence of a solvent and a polymer additive to produce a mixture comprising 3,3′-bis(halophthalimide)s, 3,4′-bis(halophthalimide)s, 4,4′-bis(halophthalimide)s, solvent and the polymer additive wherein the molar ratio of 3-halophthalic anhydride to 4-halophthalic anhydride is 98:02 to 50:50 and the molar ratio of the first diamine to the second diamine is 98:02 to 02:98; and reacting the mixture with an alkali metal salt of a dihydroxy aromatic compound to produce a polyetherimide having a cyclics content less than or equal to 5 weight percent, based on the total weight of the polyetherimide, wherein the polymer additive dissolves in the solvent at the imidization reaction temperature and pressure.

A polymer composition of cross-linked fluoropolymers is provided, that is generated using a fluoropolymer compatibilizer. The cross-linked fluoropolymers have excellent mechanical and dielectric characteristics at high temperatures, making them useful for such applications as insulation for automotive communications cables and PCB laminates.

A polymer composition of cross-linked fluoropolymers is provided, that is generated using a fluoropolymer compatibilizer. The cross-linked fluoropolymers have excellent mechanical and dielectric characteristics at high temperatures, making them useful for such applications as insulation for automotive communications cables and PCB laminates.

A polymer composition of cross-linked fluoropolymers is provided, that is generated using a fluoropolymer compatibilizer. The cross-linked fluoropolymers have excellent mechanical and dielectric characteristics at high temperatures, making them useful for such applications as insulation for automotive communications cables and PCB laminates.

The present disclosure includes thin, high-stiffness laminates, portable electronic device housings including the same, and methods for making such laminates and portable electronic device housings. Some laminates include an inner section having one or more first laminae and one or more second laminae, and first and second outer sections disposed on opposing sides of the inner section, each having one or more third laminae The laminate has a width and a length that is perpendicular to the width. Each of the first lamina(e) can have fibers aligned in a direction parallel to the length, each of the second lamina(e) can have fibers aligned in a direction parallel to the width, and each of the third lamina(e) can have fibers aligned in a direction angnlarly disposed at an angle of at least 10 degrees to each of the length and the width.

The present disclosure includes thin, high-stiffness laminates, portable electronic device housings including the same, and methods for making such laminates and portable electronic device housings. Some laminates include an inner section having one or more first laminae and one or more second laminae, and first and second outer sections disposed on opposing sides of the inner section, each having one or more third laminae The laminate has a width and a length that is perpendicular to the width. Each of the first lamina(e) can have fibers aligned in a direction parallel to the length, each of the second lamina(e) can have fibers aligned in a direction parallel to the width, and each of the third lamina(e) can have fibers aligned in a direction angnlarly disposed at an angle of at least 10 degrees to each of the length and the width.

The present disclosure relates to a method for manufacturing a polyimide film and a polyimide film manufactured thereby. In one embodiment, the method for preparing a polyimide film includes: preparing a polyamic acid by polymerizing a mixture containing an aromatic diamine and an aromatic acid dianhydride; preparing a first composition containing the polyamic acid, an amine-based catalyst, an acid anhydride-based dehydrating agent, and a solvent; and forming a polyimide film at 150° C. or less using the first composition, wherein the first composition contains the amine-based catalyst and the acid anhydride-based dehydrating agent in a molar ratio of 1:2 to 1:5.

The present invention relates to a transparent polyimide film containing a polyimide and a phosphate ester. The content of the phosphate ester based on 100 parts by mass of the polyimide is 3 parts by mass or more, preferably 5 to 100 parts by mass. It is preferable to use a phosphate ester that has a high birefringence reduction effect and with which a decrease in the tensile modulus of the film is small. In production of the polyimide film, it is preferable to employ a method in which: a solvent-soluble polyimide resin and a phosphate ester are dissolved in an organic solvent exhibiting solubility with respect to the polyimide resin to prepare a polyimide solution; the polyimide solution is applied onto a substrate; and the organic solvent is removed.

The present invention relates to a transparent polyimide film containing a polyimide and a phosphate ester. The content of the phosphate ester based on 100 parts by mass of the polyimide is 3 parts by mass or more, preferably 5 to 100 parts by mass. It is preferable to use a phosphate ester that has a high birefringence reduction effect and with which a decrease in the tensile modulus of the film is small. In production of the polyimide film, it is preferable to employ a method in which: a solvent-soluble polyimide resin and a phosphate ester are dissolved in an organic solvent exhibiting solubility with respect to the polyimide resin to prepare a polyimide solution; the polyimide solution is applied onto a substrate; and the organic solvent is removed.

Provided are a window cover film, a method of manufacturing the same, and a flexible display panel including the same. A window cover film has an excellent interlayer binding force between each layer to have significantly improved wear resistance, scratch resistance, fingerprint wipeability, and the like, while also having excellent surface properties such as a sense of touch and slip properties, a method of manufacturing the same, and a flexible display panel including the same are provided.