Accession Number : ADD014272

Title :   Pendant Benzazole Rigid-Rod Aromatic Heterocyclic Polymer.

Descriptive Note : Patent, Filed 13 Aug 87, patented 30 May 89,

Corporate Author : DEPARTMENT OF THE AIR FORCE WASHINGTON DC

Personal Author(s) : Tsai, Tsu-Tzu ; Arnols, Fred E

Report Date : 30 May 1989

Pagination or Media Count : 6

Abstract : This invention relates to para-ordered aromatic heterocyclic polymers. In one aspect, this invention relates to a method for synthesizing polymers. In general, the class of aromatic heterocyclic extended chain polymers are well known for their outstanding thermal, physical and chemical properties. These polymers generally exhibit excellent modulus and tenacity properties, but lack good properties when in compression, which limits their use as reinforcing structural fibers. It is an object of the present invention to provide novel aromatic heterocyclic polymers which exhibit improved compressive properties. The polymers of the present invention are prepared by reacting an amine monomer with heterocyclic terephthalic acid. The polymers may be prepared by: mixing an amino monomer with or without oxidation protecting atoms or groups, e.g., Hydrochloric acid groups, with a preliminary solvent of phosphoric acid having a relatively low phosphorous pentoxide content, about 63 to 83%, preferably below about 80%; heating and optionally placing the resulting mixture under reduced pressure to remove any volatile protecting atoms or groups present and provide a mixture of the amino monomer in the preliminary solvent; adding the heterocyclic terephtalic acid monomer to the mixture to provide a mixture of amino monomer and acid monomer in the preliminary solvent; increasing the phosphorous pentoxide content of the mixture to provide a reaction medium in which the percentage of phosphorous pentoxide should be about 82 to 86% PO, preferably about 82 to 84% at the end of the polymerization; and causing polymerization of the monomers at a temperature of about 100 to 200 C for about 18 to 36 hours. Keywords: Patents. (aw)

Descriptors :   *HETEROCYCLIC COMPOUNDS, *PATENTS, *POLYMERS, *SYNTHESIS(CHEMISTRY), *AZOLES, *BENZENE COMPOUNDS, ACIDS, AMINES, AROMATIC COMPOUNDS, ATOMS, CHEMICAL PROPERTIES, COMPRESSIVE PROPERTIES, FIBERS, HYDROCHLORIC ACID, MIXTURES, MONOMERS, OXIDATION, OXIDES, PHOSPHORIC ACIDS, PHOSPHORUS, PHTHALIC ACIDS, POLYMERIZATION, PRESSURE, REDUCTION, REINFORCING MATERIALS, SOLVENTS, STRUCTURAL PROPERTIES

Subject Categories : Polymer Chemistry
      Plastics
      Industrial Chemistry and Chemical Processing

Distribution Statement : APPROVED FOR PUBLIC RELEASE