Vapor Phase Patents (Class 562/896)
  • Patent number: 4857239
    Abstract: The present invention relates to a process for the synthesis of (meth)acrylic anhydride, according to which (meth)acrylic acid is reacted with acetic anhydride in the presence of at least one polymerization inhibitor, in a reactor surmounted by a distillation column. This process is characterized in that the mole ratio of (meth)acrylic acid to acetic anhydride is chosen to be between 2 and 5, in that the reaction is performed in the absence of catalyst, and in that:the acetic acid formed during the reaction is drawn off, andat least one polymerization inhibitor is gradually introduced into the top of the distillation column during the reaction and the distillation enabling the (meth)acrylic anhydride formed to be separated.The (meth)acrylic anhydrides thereby obtained are used, in particular, as reagents in the preparation of (meth)acrylates.
    Type: Grant
    Filed: April 29, 1988
    Date of Patent: August 15, 1989
    Assignee: Norsolor
    Inventors: Patrice Hurtel, Denis Laurent, Joseph Rondini