Linear, comb, and star shaped non-ionic polyesters and copolyesters, polyesteramides, polyamides, and copolyamides may be synthesized from the condensation polymerization of polyacids containing alpha-hydroxy polyacids and diols and/or polyols, and amino-diols and/or amines using boric acid, boric anhydride, and boronic acids as catalysts. Depending on the polyol, polyamine, and amino alcohol component, the resulting compound may be hydrophilic or hydrophobic, but not water soluble or dispersible, enabling use in packaging films, fibers, and other molded articles. The compounds may be completely water soluble, water dispersible, and/or amphipathic, thus being useful in cosmetics, agricultural compositions, biomedical and pharmaceutical applications.

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 viscosity modifier is thermally stable and can provide an excellent viscosity-increasing effect and/or an anti-sagging effect, and is used by the addition to a paint, a coating agent, a painting agent, a flux, an adhesive material, and a sealing material that are produced/used under high temperature conditions. A film-forming agent contains the viscosity modifier including a polyamide component that contains a polyamide compound from a C2-10 aliphatic and/or C6-10 aromatic primary diamine and a C12-36 polybasic acid and/or a C12-30 unsubstituted or hydroxy-substituted aliphatic monocarboxylic acid. The film-forming agent contains the viscosity modifier and a film-forming component and is at least any one selected from a paint, a coating material, a painting material, a flux, an adhesive material, and a sealing material.

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.

A laser-weldable composition and method using the same, said composition comprising at least one amorphous polyamide made from the polycondensation of at least an acyclic aliphatic diamine comprising at least 10 carbon atoms and/or at least an acyclic aliphatic diacid comprising at least 10 carbon atoms, and at least a phthalic acid selected from the group consisting of terephthalic acid and isophthalic acid, at least one flat glass fiber; and at least one organic dye which absorbs radiation at a wavelength from 800 to 1400 nm.

There is provided a multilayered tube for transporting liquid chemicals containing an outermost layer and an innermost layer, the innermost layer containing a polyamide (A), an impact modifier (B), and a carbon nanotube (C), wherein the number of projections each having a height of 5 μm or more and a longitudinal width of 20 μm or more, which are present on the surface of the innermost layer, is 2 or less per 1 mm.sup.2 of surface area; and the number of agglomerates each having a longitudinal width of 5 μm or more, which are present in the cross section of the innermost layer, is 15 or less per 1 mm.sup.2 of cross-sectional area. There is also provided a polyamide resin composition constituting the innermost layer of the multilayered tube for transporting liquid chemicals.

Powder compositions for laser sintering. Nylon copolymer compositions are described which provide enhanced performance in processing and finished products when used in 3D laser sintering processes.

Described herein are polymer compositions (PC) including a polyamide (PA) and a reactive impact modifier. As explained in detail below, the polyamide (PA) is a semi-aromatic polyamide derived from the polycondensation of an aliphatic diamine, a bis(aminoalkyl)cyclohexane, terephthalic acid, and, optionally, a cyclohexanedicarboxylic acid. It was surprisingly discovered that semi-aromatic polyamides derived from the cycloaliphatic diamine bis(aminoalkyl)cyclohexane or the specific combination of the cycloaliphatic diamine bis(aminoalkyl)cyclohexane and the cycloaliphatic dicarboxylic acid cyclohexanedicarboxylic acid provided for polymer compositions (PC) having improved retention of mechanical properties (e.g. tensile strength and flexural strength) after aging in aqueous solutions, relative to analogous polyamides free of the bis(aminoalkyl)cyclohexane and the cyclohexanedicarboxylic acid.

Provided is a crystalline polyamide resin that can exhibit a high mechanical strength and electrical resistance in high temperature regions (in the neighborhood of 150° C.). This polyamide resin has the following: a dicarboxylic acid-derived component unit (a) that includes a component unit (a1) derived from terephthalic acid, naphthalenedicarboxylic acid, or cyclohexanedicarboxylic acid, at more than 20 mol % and up to and including 100 mol % with reference to the total number of moles of the dicarboxylic acid-derived component unit (a); and a diamine-derived component unit (b) that contains a component unit (b1) deriving from alkylenediamine having 4-18 carbon atoms and a component unit (b2) deriving from diamine given by formula (1).

##STR00001## (in formula (1), n and the two m's are each independently 0 or 1, and —X— is a single bond or a divalent group selected from the group consisting of —O—, —S—, —SO.sub.2—, —CO—, and —CH.sub.2—)

A preparation method of a branched polyamide copolymer with ultra-high toughness is disclosed. The preparation method includes: (1) dissolving a linear dibasic acid in a solvent A to obtain a linear dibasic acid solution, dissolving a diamine B in a solvent B to obtain a diamine solution B, and dissolving a diamine C in a solvent C to obtain a diamine solution C; (2) adding the diamine solution B to the linear dibasic acid solution to obtain an amide salt solution B; and adding the diamine solution C to the linear dibasic acid solution, and collecting a precipitate to obtain an amide salt C; and (3) mixing the amide salt solution B with the amide salt C, adding a catalyst, and conducting melt polycondensation. The prepared branched copolymer has excellent mechanical performance and is suitable for melt blending toughening, melt extrusion spinning, blow-extruded films, hot melt adhesives, and other fields.