The present disclosure is related to the field of polymer materials, and, in particular, to a method for synthesizing a bio-based polyamide. More specifically, the disclosure provides a method for synthesizing a block copolymer consisting of a hard segment of a polyamide prepared via solid state polycondensation and a soft segment of a polyether polyol. Due to a reaction of itaconic acid, which contains a carbon-carbon double bond, with hexamethylenediamine, the bio-based polyamide is greatly different from conventional linear polyamides and exhibits a lower glass transition temperature and excellent mechanical properties. Unlike conventional processes for preparing modified polyamides, the bio-based polyamide is synthesized, according to the method, through chain extension of a polyamide with an excess amount of a diisocyanate based on amine value of the polyamide and then crosslinking of the resulting product with a polyether polyol by using glycerol as a crosslinking agent.

The present invention relates to a polyimide-based film exhibiting excellent visibility, a method for preparing same, and a display device including the prepared film. Particularly, the present invention relates to a polyimide-based film, a window cover film, and a display panel including same. The polyimide-based film maintains linear polarization with respect to incident polarization in the direction of an inclination as well as incident polarization in the direction of a normal line of the film.

Techniques regarding chemical compounds with antimicrobial functionality are provided. For example, one or more embodiments describe herein can comprise a monomer that can comprise a molecular backbone. The molecular backbone can comprise a bis(urea)guanidinium structure covalently bonded to a functional group, which can comprise a radical. Also, the monomer can have supramolecular assembly functionality.

Techniques regarding chemical compounds with antimicrobial functionality are provided. For example, one or more embodiments describe herein can comprise a monomer that can comprise a molecular backbone. The molecular backbone can comprise a bis(urea)guanidinium structure covalently bonded to a functional group, which can comprise a radical. Also, the monomer can have supramolecular assembly functionality.

A polyamide resin composition containing, per 100 parts by mass of a particular polyamide (A), 45 to 120 parts by mass of an inorganic filler (B), 25 to 40 parts of at least one kind of a phosphinate salt (C) represented by the particular formula, 2 to 15 parts by mass of a phosphite salt (D), and a colorant (E), having a sulfur element content of less than 220 ppm by mass and ΔE represented by the following expression (1) of more than 1, and a molded body thereof:

ΔE=[(L*.sub.col.Math.L*.sub.nat).sup.2+(a*.sub.col.Math.a*.sub.nat).sup.2+(b*.sub.col.Math.b*.sub.nat).sup.2].sup.1/2  (1)

wherein the symbols in the expression are defined in the description.

A polyamide resin composition containing, per 100 parts by mass of a particular polyamide (A), 45 to 120 parts by mass of an inorganic filler (B), 25 to 40 parts of at least one kind of a phosphinate salt (C) represented by the particular formula, 2 to 15 parts by mass of a phosphite salt (D), and a colorant (E), having a sulfur element content of less than 220 ppm by mass and ΔE represented by the following expression (1) of more than 1, and a molded body thereof:

ΔE=[(L*.sub.col.Math.L*.sub.nat).sup.2+(a*.sub.col.Math.a*.sub.nat).sup.2+(b*.sub.col.Math.b*.sub.nat).sup.2].sup.1/2  (1)

wherein the symbols in the expression are defined in the description.

The present disclosure relates to a method of selecting a polymer solution (also referred to as a “dope solution”) that is prepared by dissolving a polymer in a solvent in order to cast a film and may provide excellent optical and mechanical properties of the film, a polymer solution prepared using the selected solvent, and a film produced using the polymer solution. In addition, one embodiment is to provide a method of selecting a solvent for a polyamideimide-based or polyimide-based polymer for providing a polymer solution (dope solution) that may provide excellent optical properties of a film and may provide excellent physical properties of a film for an optical device or a display device by improving long-term storage stability of the polymer solution for producing a film.

In an example of a method for three-dimensional (3D) printing, a build material composition is applied to form a build material layer. The build material composition includes a polymeric or polymeric composite build material, and a precipitating agent. Based on a 3D object model, a fusing agent is selectively applied on at least a portion of the build material composition. The fusing agent includes a radiation absorber, which the precipitating agent precipitates. The build material composition is exposed to radiation to fuse the at least the portion to form a layer of a 3D part.

A method for preparing a high molecular weight furan polyamide includes the following steps: 1) charging dimethyl furan dicarboxylate and aliphatic diamine into a reaction container at equal molar weight, and increasing the temperature to 60-120° C. under inert gas; 2) adding a catalyst when the reaction system becomes transparent liquid, increasing the temperature to 140-150° C., and keeping at an atmospheric pressure or a pressure of 41-61 kPa for 0-1 h; and then increasing the temperature to 190-200° C. and reacting for 1-3 h; and 3) depressurizing the system to 3-16 kPa for 0-3 h; and finally, reducing the pressure to 0.003-0.100 KPa for 1-3 h to obtain the high molecular weight furan polyamide.

The present invention relates to a composite semipermeable membrane including a supporting membrane and a separation functional layer disposed on the supporting membrane, in which the separation functional layer comprises an aromatic polyamide, the aromatic polyamide has side chains and terminal groups, at least one of the side chains and terminal groups of the aromatic polyamide being an amino group, at least one of the side chains and terminal groups of the aromatic polyamide is a substituent having a structure represented by formula (1): —NXY or formula (2): —NXYZ, and in the aromatic polyamide, a content A of substituents having structures represented by formula (1) and formula (2) and a content B of amide groups satisfy 0.005≦A/B≦0.15.