Abstract:
Liquid crystal polyester derived from phenylene-naphthalene monomers and one or more comonomers display an improved balance of properties, including low melt viscosity, fast cycle time in molding, very low mold shrinkage, high tensile and/or flexural strength, solvent resistance, excellent barrier properties, low water absorption, low thermal expansion coefficient, excellent thermostability, and/or low flammability. The phenylene-naphthalene monomers are The one or more comonomers include 4-hydroxybenzoic acid, 2-hydroxy-6-naphthoic acid, terephthalic acid, isophthalic acid, and derivatives and combinations thereof.
Abstract:
Liquid crystal polyester derived from phenylene-naphthalene monomers and one or more comonomers display an improved balance of properties, including low melt viscosity, fast cycle time in molding, very low mold shrinkage, high tensile and/or flexural strength, solvent resistance, excellent barrier properties, low water absorption, low thermal expansion coefficient, excellent thermostability, and/or low flammability. The phenylene-naphthalene monomers are The one or more comonomers include 4-hydroxybenzoic acid, 2-hydroxy-6-naphthoic acid, terephthalic acid, isophthalic acid, and derivatives and combinations thereof.
Abstract:
Methods for forming core-shell magnetic nanoparticles are provided. The method can include: forming an oxide shell around a metal oxide core to form a core-shell magnetic nanoparticle; attaching an anchoring agent to the magnetic nanoparticle; reacting a RAFT agent with the functional group of the anchoring agent such that the RAFT agent is bonded to the magnetic nanoparticle through the anchoring agent; and attaching a polymeric chain to the RAFT agent.
Abstract:
The present invention relates to a novel proton-conducting polymer membrane based on polyazole block polymers which, owing to their outstanding chemical and thermal properties, can be used widely and are suitable in particular as polymer electrolyte membrane (PEM) for producing membrane electrode units or so-called PEM fuel cells.
Abstract:
Electrical insulation comprising a polymeric matrix having compounded therein, a functionalized dielectric nanoparticle filler comprising a self-healing moiety, dispersible in the polymeric matrix, wherein the electrical insulation is capable of self-healing upon exposure to corona discharge.
Abstract:
The present invention relates to novel polyazoles, a proton-conducting polymer membrane based on these polyazoles and its use as polymer electrolyte membrane (PEM) for producing membrane-electrode units for PEM-fuel cells, and also other shaped bodies comprising such polyazoles.
Abstract:
The present invention relates to novel polyazoles, a proton-conducting polymer membrane based on these polyazoles and its use as polymer electrolyte membrane (PEM) for producing membrane-electrode units for PEM-fuel cells, and also other shaped bodies comprising such polyazoles.
Abstract:
The invention under consideration concerns novel his-molecular-weight polyazoles, which are suitable for the production of fibers, films, membranes, and molded articles, on the basis of their high molecular weight, expressed as intrinsic viscosity, of at least 1.3 dl/g. Moreover, the invention under consideration describes a method for the production of high-molecular-weight polyazoles.
Abstract:
The invention relates to a modified nanoparticle including a nanoparticle and a diblock copolymer covalently attached to the nanoparticle, the diblock copolymer comprising a first block polymer of molecular weight greater than 1000 attached to the nanoparticle and a second block polymer of molecular weight greater than 1000 covalently linked to the first block polymer, wherein at least one of the first block polymer and second block polymer comprises repeating units having an azide, acetylene or triazole side chain. Nanocomposites incorporating modified nanoparticles, as well as methods of making modified nanoparticles and nanocomposites are also disclosed.
Abstract:
A proton-conducting polymer membrane comprising polyazoles containing sulfonic acid groups is obtainable by a process comprising: A) mixing one or more aromatic or heteroaromatic tetraamino compounds with one or more aromatic or heteroaromatic carboxylic acids or derivatives thereof which contain at least two acid groups per carboxylic acid monomer, with at least part of the tetraamino compounds or the carboxylic acids comprising at least one sulfonic acid group, or mixing of one or more aromatic or heteroaromatic diaminocarboxylic acids, of which at least part comprises sulfonic acid groups, in polyphosphoric acid to form a solution or dispersion; B) optionally heating the solution or dispersion obtained by step A) under inert gas to temperatures of up to 325° C. to form polyazole polymers; C) applying a layer using the mixture from step A) or B) to a support, thus forming a membrane, and D) partially hydrolyzing the polyphosphoric acid moieties of the membrane from step C) until it is self-supporting.