Process for manufacturing high purity methacrylic acid
    13.
    发明授权
    Process for manufacturing high purity methacrylic acid 有权
    制造高纯度甲基丙烯酸的方法

    公开(公告)号:US07723541B2

    公开(公告)日:2010-05-25

    申请号:US11521744

    申请日:2006-09-15

    IPC分类号: C07C57/02 C07C51/08

    摘要: A process is provided herein for the high yield production of high purity glacial methacrylic acid (“HPMAA”) that is substantially pure, specifically 99% pure or greater, with water content of 0.05% or less and low levels of other impurities, including HIBA, acrylic acid, MOMPA, methacrolein and others. This improved process comprises providing a crude MAA stream and purifying the crude methacrylic acid stream in a series of successive distillation steps involving two distillation columns. The inventive process is capable producing high purity methacrylic acid product that is especially suitable for the production of specialty MAA polymers.

    摘要翻译: 本文提供了一种高产量生产高纯度冰甲基丙烯酸(“HPMAA”)的方法,其基本上纯,特别是99%纯或更高,水含量为0.05%或更低,其他杂质含量低,包括HIBA ,丙烯酸,MOMPA,异丁烯醛等。 该改进的方法包括提供粗MAA流并在涉及两个蒸馏塔的一系列连续蒸馏步骤中纯化粗甲基丙烯酸流。 本发明的方法能够生产特别适用于生产特种MAA聚合物的高纯度甲基丙烯酸产品。

    Conversion of Nitrile Compounds Into Carboxylic Acids and Corresponding Esters Thereof
    14.
    发明申请
    Conversion of Nitrile Compounds Into Carboxylic Acids and Corresponding Esters Thereof 有权
    腈化合物转化为羧酸及其相应酯

    公开(公告)号:US20090326260A1

    公开(公告)日:2009-12-31

    申请号:US12308176

    申请日:2007-05-25

    IPC分类号: C07C67/00 C07C51/08

    摘要: Hydrocarbon-based compounds containing at least one nitrile function are converted into compounds containing at least one carboxylic function, and into ester compounds from the carboxylic compounds thus obtained; such conversion entails reacting the nitrile compound with a hydroxyl basic compound in solution in a solvent at a temperature of between 80 and 150° C., in eliminating the ammonia formed, in reacting the salt obtained with a mineral acid, and then in recovering the compound containing at least one carboxylic function and, optionally, esterifying the acids obtained by reaction with an alcohol.

    摘要翻译: 含有至少一个腈官能团的烃基化合物被转化成含有至少一个羧酸官能团的化合物,并由如此获得的羧酸化合物转化为酯化合物; 这种转化需要使腈化合物与溶剂中的羟基碱性化合物在溶剂中在80-150℃的温度下反应,以消除所形成的氨与无机酸反应获得的盐,然后回收 含有至少一个羧酸官能团的化合物,和任选地,通过与醇反应获得的酸酯化。

    Method for preparing aromatic compounds
    19.
    发明授权
    Method for preparing aromatic compounds 失效
    芳香族化合物的制备方法

    公开(公告)号:US5849934A

    公开(公告)日:1998-12-15

    申请号:US20573

    申请日:1998-01-28

    摘要: A perfluorinated polyimide comprising a repeating unit represented by general formula (1): ##STR1## and a perfluorinated poly(amic acid) comprising a repeating unit represented by general formula (6): ##STR2## wherein R.sub.1 is a tetravalent organic group; and R.sub.2 is a divalent organic group, provided that chemical bonds between carbon atoms and monovalent elements contained in R.sub.1 and R.sub.2 are exclusively carbon-to-fluorine bonds; methods for preparing them; and optical material including the perfluorinated polyimide. 1,4-Bis(3,4-dicarboxytrifluorophenoxy)-tetrafluorobenzene dianhydride, 1,4-difluoropyromellitic anhydride, 1,4-bis(3,4-dicarboxytrifluorophenoxy)-tetrafluorobenzene, 1,4-difluoropyromellitic acid, and 1,4-bis(3,4-dicyanotrifluorophenoxy)-tetrafluorobenzene as well as methods preparing them. The perfluorinated polyimide has a thermal stability and has a low optical loss in an optical communication wavelength region (0.8 to 1.7 .mu.m).

    摘要翻译: 一种全氟化聚酰亚胺,其包含由通式(1)表示的重复单元:(IMAG)(1)和包含由通式(6)表示的重复单元的全氟化聚(酰胺酸):其中R1是 四价有机基团; 并且R2是二价有机基团,条件是R1和R2中包含的碳原子和一价元素之间的化学键仅为碳 - 氟键; 制备方法 和包括全氟化聚酰亚胺的光学材料。 1,4-二(3,4-二羧基三氟苯氧基) - 四氟苯二酸酐,1,4-二氟苯
    二甲酸酐,1,4-双(3,4-二羧基三氟苯氧基) - 四氟苯,1,4-二氟苯甲酸酐, 双(3,4-二氰基三氟苯氧基) - 四氟苯以及制备它们的方法。 全氟聚酰亚胺具有热稳定性,并且在光通信波长区域(0.8-1.7μm)中具有低光损耗。