A customizable polyamide polymer, in particular Nylon 66, Nylon 6, and copolyamides, having a high molecular weight, excellent color, and low gel content is disclosed. In particular, disclosed is a polymer having a relative viscosity greater than 50 as measured in a 90% strength formic acid solution; consistent viscosity with a standard deviation of less than 1; a gel content no greater than 50 ppm as measured by insolubles larger than 10 micron; an optical defect content of less than 2,000 parts per million (ppm) as measured by optical control system (OCS). The polymer can be made into monofilaments or a multifilament yarn.

A customizable polyamide polymer, in particular Nylon 66, Nylon 6, and copolyamides, having a high molecular weight, excellent color, and low gel content is disclosed. In particular, disclosed is a polymer having a relative viscosity greater than 50 as measured in a 90% strength formic acid solution; consistent viscosity with a standard deviation of less than 1; a gel content no greater than 50 ppm as measured by insolubles larger than 10 micron; an optical defect content of less than 2,000 parts per million (ppm) as measured by optical control system (OCS). The polymer can be made into monofilaments or a multifilament yarn.

A method for preparing an anti-bacterial and anti-ultraviolet multifunctional chemical fiber includes: dissolving several soluble metal salts and a polymer complexing dispersant into water to prepare an aqueous solution; adding into a polymer monomer; reacting under microwave or hydrothermal action to obtain a polymer monomer containing multifunctional nano oxides; adding the polymer monomer with other monomer, catalyst, initiator, stabilizer, and the like into a polymerization reactor; and carrying out esterification, polycondensation or copolymerization to obtain a polymer melt, and carrying out spinning or ribbon casting and granule cutting to obtain an anti-bacterial and anti-ultraviolet multifunctional chemical fiber or masterbatch chips. By generating nano metal oxides in the monomer in situ before the polymerization reaction, small particle sizes and dispersibility of the nano metal oxide are ensured; the chemical fiber has efficient, durable antibacterial and anti-ultraviolet functions and is free of metal ion precipitation.

The present invention relates to a process for preparing a granular nylon salt material, wherein an aqueous mixture, comprising at least 65 wt. % of salt components, and at most 35 wt. % of an aqueous medium, the weight percentages (wt. %) being relative to the total weight of the aqueous mixture, is flashed from a pressure vessel via a flash valve into a flash chamber, thereby evaporating the aqueous medium in an amount sufficient to result in a residual moisture content of at most 7.5 wt. %, and forming a granular nylon salt material. The invention also relates to a process for preparing a nylon polymer, comprising direct solid state polymerization of the granular salt material prepared by flash granulation.

The present invention relates to a process for preparing a granular nylon salt material, wherein an aqueous mixture, comprising at least 65 wt. % of salt components, and at most 35 wt. % of an aqueous medium, the weight percentages (wt. %) being relative to the total weight of the aqueous mixture, is flashed from a pressure vessel via a flash valve into a flash chamber, thereby evaporating the aqueous medium in an amount sufficient to result in a residual moisture content of at most 7.5 wt. %, and forming a granular nylon salt material. The invention also relates to a process for preparing a nylon polymer, comprising direct solid state polymerization of the granular salt material prepared by flash granulation.

The present invention provides a semi-aromatic polyamide resin which is excellent in heat resistance and heat discoloration resistance, which can suppress a mold staining due to outgassing during melt molding, and which is excellent in melt fluidity, gelation characteristics and mechanical properties, wherein the semi-aromatic polyamide resin contains a constituent unit obtained from hexamethylenediamine and terephthalic acid and a constituent unit obtained from 11 -aminoundecanoic acid or undecane lactam, wherein a relative viscosity (RV) of the semi-aromatic polyamide resin is within a range of 2.65 to 3.50, and wherein a relationship among a concentration of terminal amino groups (AEG), a concentration of terminal carboxyl groups (CEG) and a concentration of terminal amino groups blocked by a monocarboxylic acid (EC) satisfies the specific formulae.

The invention relates to a 3D printable powder composition comprising a polyamide and less than 5 wt % by weight of at least one filler. The invention also relates to the process for preparing the 3D printable powder, and its use for the preparation of a 3D printed article.

The invention relates to a 3D printable powder composition comprising a polyamide and less than 5 wt % by weight of at least one filler. The invention also relates to the process for preparing the 3D printable powder, and its use for the preparation of a 3D printed article.

A base polyamide composition comprising a nylon mixture having caprolactam units from 1 wppb to 50 wppm catalyst composition; and greater than 0.75 wt % residual caprolactam, wherein the base polyamide composition has a delta end group level ranging from 30 μeq/gram to 90 μeq/gram.

Processes for preparing a polyamide, a polyamide material obtained by such processes, a nylon salt to be used therein, and processes for making the nylon salt are disclosed. The processes for preparing the polyamide include a direct solid state polymerization process. The salt used herein is a granulate material, prepared by a process, comprising spraying an aqueous solution comprising a diamine and a dicarboxylic acid dissolved in an aqueous medium, or an aqueous slurry comprising a diammonium dicarboxylate salt dispersed in an aqueous medium directly obtained from such an aqueous solution, onto or in a fluidized bed of diammonium dicarboxylate salt particles, while evaporating the aqueous medium, thereby forming a granulate salt material.