Provided herein is a polymer composition comprising an aromatic polyamide comprising terephthalic units and isophthalic units or a 6T/DT copolymer and having an overall high aromaticity, with a heat stabilizer and/or a lubricant. The polymer composition demonstrates improved electrical performance in terms of volume resistivity and dielectric strength.

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.

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.

The invention relates to a process for preparing a semi-aromatic polyamide from diamine and dicarboxylic acid, comprising steps of •(i) dosing a liquid diamine to an agitated powder comprising an aromatic dicarboxylic acid thereby forming a powder comprising a diamine/dicarboxylic acid salt (DD-salt), and •(ii) solid-state polymerizing the DD-salt to obtain the polyamide.

A multilayer tubular structure (MLT) for transporting fluids for a motor vehicle, including at least three layers: at least one layer having a composition predominantly including at least one semi-crystalline aliphatic polyamide, the composition having at least 50% of recycled material from a single-layer and/or multilayer tube that has been intended for transporting fluids for a motor vehicle, the tube having a composition which predominantly includes at least one polyamide, at least one layer having a composition predominantly including at least one semi-crystalline aliphatic polyamide and optionally at least one impact modifier, and when the layer has a composition predominantly including at least one semi-crystalline aliphatic polyamide that is PA12 and/or PA612 and/or PA1010, then the composition includes the impact modifier, and at least one layer having a composition predominantly including at least one semi-crystalline aliphatic polyamide, the layer and the layer each having at least 90% of non-recycled material.

A multilayer tubular structure for transporting fluids for a motor vehicle, including at least three layers: at least one layer having a composition predominantly including at least one semi-crystalline aliphatic polyamide, the composition having at least 50% of recycled material from a multilayer tube that has been intended for transporting fluids for a motor vehicle, the tube having a composition which predominantly includes at least one polyamide, at least one layer having a composition predominantly including at least one semi-crystalline aliphatic polyamide and optionally at least one impact modifier, and when the layer has a composition predominantly including at least one semi-crystalline aliphatic polyamide that is PA12 and/or PA612 and/or PA1010, then the composition includes the impact modifier, and at least one layer having a composition predominantly including at least one semi-crystalline aliphatic polyamide, the layer and the layer each having at least 90% of non-recycled material.

A multilayer tubular structure for transporting fluids for a motor vehicle, the structure including at least three layers: at least one layer having a composition predominantly including at least one semi-crystalline aliphatic polyamide, the composition having at least 50% of recycled material from a single-layer and/or multilayer tube that has been intended for transporting fluids for a motor vehicle, the tube having a composition which predominantly includes at least one polyamide, at least one layer having a composition predominantly including at least semi-crystalline aliphatic polyamide and optionally at least one impact modifier, and when the layer has a composition predominantly including at least one semi-crystalline aliphatic polyamide that is PA12 and/or PA612 and/or PA1010, then the composition includes the impact modifier, and at least one barrier layer, the layer and the barrier layer each having at least 90% of non-recycled material.

A metal adsorbent that includes silver-decorated graphene nano-platelets and a polymer matrix that comprises polyamide, wherein the metal adsorbent is a highly porous material with a specific surface area of 200 to 300 m.sup.2/g and an average pore size of 50 to 100 Å, which effective removes heavy metals and cations from a liquid. Various embodiments of the metal adsorbent and a method of making thereof are also provided.

A metal adsorbent that includes silver-decorated graphene nano-platelets and a polymer matrix that comprises polyamide, wherein the metal adsorbent is a highly porous material with a specific surface area of 200 to 300 m.sup.2/g and an average pore size of 50 to 100 Å, which effective removes heavy metals and cations from a liquid. Various embodiments of the metal adsorbent and a method of making thereof are also provided.

A hot water storage device having a vessel includes a first section formed from a moulded material and a second section formed from a moulded material. An open end of the first section is sealingly engaged with an opposing open end of the second section to form the vessel. The first and second sections each have a generally cylindrical body portion and a closed end, comprising a head portion. The vessel includes a water inlet aperture moulded into the first or second section and a water outlet aperture moulded into the first or second section and wherein the inlet and outlet apertures are located on the body portion proximal to a tangent line between the body portion and the head portion.