52256-80-1Relevant academic research and scientific papers
METHOD FOR PURIFICATION OF A BISPHENOL A DIANHYDRIDE COMPOSITION, BISPHENOL A DIANHYDRIDE COMPOSITION, POLY(ETHERIMIDE) DERIVED FROM THE BISPHENOL A DIANHYDRIDE COMPOSITION, AND ARTICLES PREPARED THEREFROM
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Paragraph 0060-0064, (2020/08/22)
A method for the purification of a bisphenol A dianhydride composition includes contacting the bisphenol A dianhydride composition with a halogenated solvent to form a solution, and one or more of filtering the solution to remove ionic species; washing the solution with aqueous media to remove ionic species; crystallizing bisphenol A dianhydride from the solution to remove ionic species; and contacting the solution with an adsorbent to remove ionic species. A purified bisphenol A dianhydride composition is also described. The bisphenol A dianhydride composition can be used in the preparation of a poly(etherimide), and poly (etherimides) made from the bisphenol A dianhydride composition can be useful for forming a variety of articles.
Preparation method of aromatic diether dianhydride
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Paragraph 0075; 0078, (2019/12/02)
The invention relates to a preparation method of aromatic diether dianhydride, which comprises the following steps: (1) pouring a bisphenol compound, N-substituted phthalimide and a catalyst into a mixed solvent, carrying out heating reflux to remove water and carrying out substitution reaction to obtain N-substituted diether imide; (2) adding alkali metal hydroxide and water into the N-substituted diether imide obtained in the step (1), heating the mixture, carrying out hydrolysis reaction, cooling, adding protonic acid, separating out solid, collecting the solid, and drying the solid; and (3) dissolving the dried solid in a mixed solution of acetic acid and acetic anhydride, carrying out heating reflux, cooling, filtration and solid collection in sequence, recrystallizing the collected solid with a mixed solution of acetonitrile and toluene, performing filtration, collecting the solid, and drying the solid to obtain the product. The preparation method of the aromatic diether dianhydride has the advantages that the steps are simplified, the consumed time is short, the used solvent is easy to recycle and can be repeatedly used, and the prepared product aromatic diether dianhydrideis high in purity and yield.
Direct dianhydride synthesis
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Page/Page column 6, (2008/06/13)
This invention is related to a method for making diether dianhydrides by the reaction of halophthalic anhydride and a metal salt of an aromatic dihydroxy compound in the presence of a solvent and a phase transfer catalyst. Typical phase transfer catalyst include guanidium salts, aminopyridinium salts, or phosphazenium salts.
A comparison of poly(ether imide)s with 3-phthalimide and 4-phthalimide units: Synthesis, characterization, and physical properties
Eastmond,Paprotny,Pethrick,Santamaria-Mendia
, p. 7534 - 7548 (2007/10/03)
Bis(ether anhydride)s with 3- or 4-phthalimide moieties were prepared by reacting 3- or 4-nitrophthalodinitrile, respectively, with several diols and converting the resulting bis(ether dinitrile)s to bis(ether anhydride)s. Selected dianhydrides were converted into poly(ether imide)s in a two-stage solution polymerization and imidization process. It was found that, in most cases, the dianhydrides with 4-phthalic anhydride units gave high-molecular-weight polymers with any of several aromatic diamines. In contrast, dianhydrides with 3-phthalic anhydride units gave, primarily, low-molecular-weight products. Examination of several low-molecular-weight products by electrospray-ionization mass spectrometry demonstrated that the products consisted of small oligomers, cyclic or linear according to the structure of the diamine. A series of high-molecular-weight polymers were prepared from 4,4′-bis(4″-aminophenoxy)biphenyl (BAPB) and each of several bis(ether anhydride)s with 3- or 4-phthalic anhydride units; the anhydrides had isopropylidine or hexafluoroisopropylidine units or ortfto-methyl or ortho-tert-butyl substituents in the diol residues. These polymers were characterized in terms of their molecular weights and glass-transition temperatures. The gas permeabilities, positron annihilation, and dielectric relaxation behaviors of the polymers were investigated and their properties related to their molecular structures. Dielectric relaxation spectroscopy measurements indicate that, in this group of polymers, the rates of the local chain mobility are comparable and are able to facilitate gas diffusion. An apparent linear correlation between the permeation coefficients and free volume as determined by positron annihilation lifetime spectroscopy was observed with certain gases. Comparison of polymers with similar molecular structures indicated that isomeric polymers with 3- and 4-linked phthalimide units have similar properties and that the introduction of branched chains or fluorinated groups leads to an increase in the free volume and consequently increased permeability.
