摘要:
Disclosed is a method for removing a neutral or an ionic guanidine compound from aqueous media optionally comprising an alkali metal halide, wherein the method is selected from the group consisting of (a) adsorption onto a carbonaceous adsorbent, (b) adsorption onto a clay adsorbent, (c) filtration through a nanofiltration membrane, and (d) removal of water and calcination.
摘要:
Disclosed herein is a method comprising: (a) adding an aqueous solution comprising a quaternary ammonium salt to an organic solvent in a vessel under an inert atmosphere, thereby forming a first mixture comprising the quaternary ammonium salt and the solvent; and (b) mixing the first mixture at a temperature and for a time sufficient to remove water and a portion of the solvent from the first mixture, wherein the mixing is performed in an inert atmosphere and the temperature is less than the decomposition temperature of the quaternary ammonium salt.
摘要:
Disclosed is a method for preparing an alkali metal salt of a hydroxy-substituted hydrocarbon which comprises the steps of (i) contacting in solvent media at least one hydroxy-substituted hydrocarbon with a base comprising an alkali metal cation; and (ii) devolatilizing the solvent media comprising alkali metal salt by adding or spraying the solvent media into a substantially water-immiscible organic solvent, said solvent being at a temperature greater than the boiling point of solvent media at the prevailing pressure. In one embodiment the solvent media comprises water, and optionally at least one water-soluble protic organic solvent.
摘要:
Disclosed herein is a method comprising: (a) adding an aqueous solution comprising a quaternary ammonium salt to an organic solvent in a vessel under an inert atmosphere, thereby forming a first mixture comprising the quaternary ammonium salt and the solvent; and (b) mixing the first mixture at a temperature and for a time sufficient to remove water and a portion of the solvent from the first mixture, wherein the mixing is performed in an inert atmosphere and the temperature is less than the decomposition temperature of the quaternary ammonium salt.
摘要:
Bis(halophthalimides) are prepared in mixture in an organic liquid such as ortho-dichlorobenzene or anisole, by a reaction at a temperature of at least 150° C. between at least one diamine compound and at least one halophthalic anhydride in the presence of imidization catalyst. The reaction mixture is maintained at about 15% by weight solids content and rich in the halophthalic anhydride by constantly monitoring the reaction mixture using analytical methods such as high performance liquid chromatography. The product mixture may be directly employed in the direct preparation of polyetherimides, and similar slurries may be employed to prepare other polyether polymers.
摘要:
A method for the manufacture of a polyetherimide composition includes catalyzing the reaction of a dianhydride and an organic diamine with a catalyst selected from guanadinium salts, pyridinium salts, imidazolium salts, tetra(C6-24)aryl ammonium salts, tetra(C7-24 arylalkylene) ammonium salts, dialkyl heterocycloaliphatic ammonium salts, bis-alkyl quaternary ammonium salts, (C7-24arylalkylene)(C1-16alkyl) phosphonium salts, (C6-24aryl)(C1-16alkyl)phosphonium salts, phosphazenium salts and combinations thereof, optionally in the presence of a solvent.
摘要:
A polyetherimide having an OH content that is greater than 0 and equal or less than 100 ppm; a Relative Thermal Index that is greater than or equal to 170° C.; and a chlorine content that is greater than 0 ppm is disclosed herein. A method for preparing the polyetherimide is also disclosed.
摘要:
Polyether polymers, such as polyetherimides, are prepared by the reaction of a dihydroxy-substituted aromatic hydrocarbon alkali metal salt, such as bisphenol A disodium salt, with a bis(N-(chlorophthalimido))aromatic compound, such as 1,3- and/or 1,4-bis(N-(4-chlorophthalimido))benzene, in a solvent such as o-dichlorobenzene and in the presence of a phase transfer catalyst such as a hexaalkylguanidinium chloride. Several embodiments may be employed to improve the method. They comprise employing substantially dry reagents, employing a high solids level in solvent, beginning with an excess of bis(N-(chlorophthalimido))-aromatic compound and incrementally adding alkali metal salt, employing alkali metal salt of small particle size, and using reagents of high purity.
摘要:
A method of manufacture of a bis(phthalimide) composition includes reacting, in the presence of a solvent and a catalytically active amount of an imidization catalyst selected from quaternary ammonium salts, quaternary phosphonium salts, and combinations thereof, a substituted phthalic anhydride with an organic diamine, wherein conversion to the bis(phthalimide) is 99% complete in less than 6 hours.
摘要:
A method for the manufacture of a polyetherimide composition includes catalyzing the reaction of a dianhydride and an organic diamine with a catalyst selected from guanadinium salts, pyridinium salts, imidazolium salts, tetra(C6-24)aryl ammonium salts, tetra(C7-24 arylalkylene)ammonium salts, dialkyl heterocycloaliphatic ammonium salts, bis-alkyl quaternary ammonium salts, (C7-24arylalkylene)(C1-16alkyl)phosphonium salts, (C6-24aryl)(C1-16alkyl)phosphonium salts, phosphazenium salts and combinations thereof, optionally in the presence of a solvent.