Method of producing a thermosetting esterimide oligomer

{
  "publication_number": "US5391697A",
  "country": "US",
  "kind": "A",
  "title": "Method of producing a thermosetting esterimide oligomer",
  "abstract": "Thermosetting esterimide oligomers of formulas (IA) and (IB) are disclosed: (IA) (IB) where A1, A2 and A4 are divalent organic groups, A3 is a monovalent organic group and A1, A2, A3 and A4 may be the same or different, with m being an integer of 1-30. The above compounds provide hard substances having excellent workability, heat resistance and mechanical properties.",
  "claims": [
    "1. A method for producing an esterimide oligomer, which comprises: keeping a reaction system at room temperature or below in an inert gas atmosphere, adding trimellitic acid anhydride dissolved in an aprotic polar solvent to a mixed solution containing paratoluenesulfonic acid chloride and pyridine, adding a diol dissolved in an aprotic polar solvent to cause a reaction to proceed, adding the necessary quantity of a diamine dissolved in an aprotic polar solvent for obtaining both end acid anhydride groups-terminated telechelic oligoesteramic acid, adding a primary amine or an acid anhydride dissolved in an aprotic polar solvent to terminate the both ends, and adding a non-solvent to dehydrate and close rings of the reaction product.",
    "2. A method as claimed in claim 1, wherein the aprotic polar solvent is dimethylformamide.",
    "3. A method as claimed in claim 1, wherein an organic tetracarboxylic acid dianhydride is added to said reaction system together with said diol.",
    "4. A method as claimed in claim 2, wherein an organic tetracarboxylic acid dianhydride is added to said reaction system together with said diol.",
    "5. A method as claimed in claim 1, wherein said non-solvent is an aromatic hydrocarbon selected from the group consisting of xylene, toluene and benzene."
  ],
  "cpc": [
    "C07D 209/48",
    "C08G 73/101",
    "C08G 73/16"
  ],
  "assignees": [
    "KANEGAFUCHI CHEMICAL IND"
  ],
  "filing_date": "1994-03-08",
  "publication_date": "1995-02-21",
  "grant_date": "1995-02-21",
  "priority_date": "1990-07-25",
  "application_number": "US-20704794-A",
  "family_id": "26510051",
  "citations": [
    "JPH01123819A",
    "JPS53119865A",
    "US3852246A",
    "US4290929A",
    "US4362861A",
    "US4757118A",
    "US4861857A"
  ]
}