Accession Number : ADA260466


Title :   Processable Precursors to High Performance Liquid Crystalline Polymers.


Descriptive Note : Final technical rept. 1990-1992,


Corporate Author : MORRIS BROWN COLL ATLANTA GA


Personal Author(s) : Harruna, I I


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a260466.pdf


Report Date : Oct 1992


Pagination or Media Count : 5


Abstract : Processable precursor polymers to aramids, poly(imino1,4- phenyleneiminocarbonyl-1,4 phenylenecarbonyl) and poly(imino-1,3- phenyleneiminocarbonyl-1,4-phenylenecarbonyl), were prepared and studied. The precursor polymers were made from the reaction of 2,5-dichlorobicyclo2.2. 2octane-1,4dicarbonyl chloride or 2,5diacetoxybicyclo2.2.2octane-1,4- dicarboxylic acid. The polymeric precursors were subsequently converted in approximately 98% - 100% yields, via dehdrohalogenation and retro Diels-Alder reactions to the corresponding aramids by refluxing in 1M solution of potassium hydroxide or sodium hydroxide, or by bulk pyrolysis using aromatization catalysts, such as, ZnCl 2 and dichlorobenzene sulfonic acid. Only the p- phenylene precursor polymer exhibited liquid crystal characteristics in solution. Thermal properties were examined and tensile properties will be determined In a future study.


Descriptors :   *POLYMERS , *PRECURSORS , *LIQUID CRYSTALS , THERMAL PROPERTIES , LINEAR SYSTEMS , TENSILE PROPERTIES , YIELD , SOLVENTS , MELTING POINT , DIENE SYNTHESIS , SODIUM HYDROXIDE , SULFONIC ACIDS , CARBONYL COMPOUNDS , ACIDS , CARBOXYLIC ACIDS , PYROLYSIS , POTASSIUM , HYDROXIDES , ZINC COMPOUNDS , CATALYSTS , CHLORIDES , CRYSTALS , SODIUM , PROCESSING , BENZENE , LIQUIDS


Subject Categories : Organic Chemistry
      Physical Chemistry
      Polymer Chemistry
      Crystallography


Distribution Statement : APPROVED FOR PUBLIC RELEASE