Accession Number : AD0455622


Title :   POLY(1,3,4-OXADIAZOLE) AND RELATED POLYMERS FOR THERMALLY-STABLE FIBERS.


Descriptive Note : Rept. for 1 Jul 62-1 May 64,


Corporate Author : DU PONT DE NEMOURS (E I) AND CO WILMINGTON DE


Personal Author(s) : Frazer, A H ; Fitzgerald, W P ; Reed, T A


Report Date : Aug 1964


Pagination or Media Count : 53


Abstract : High molecular weight polyhydrazide (OIOT) was prepared. This material was spun from DMSO and DMAc and the resultant fibers subjected to drawing studies. Highly drawn OIOT fibers were converted to polyoxadiazole (PODZ) fiber by thermal cyclodehydration. This tough, highly oriented, crystalline fiber maintained over 60% of its straight tenacity after heating for 24 hrs at 400 C. in air. Undrawn OIOT fiber converted to PODZ much more rapidly than drawn OIOT fiber. Conversion of undrawn OIOT yarn by thermal cyclodehydration followed by appropriate drawing produced a PODZ having T/E/M of 4.0/10/164. Thermal half tenacity life of this unique high modulus PODZ lies between 24 and 36 hrs at 400 C. in air. A route to fiber containing the 2,5(m/p-phenylene)-1,3,4-thiadiazole structure was found. Polythiadiazole yarn exhibited excellent thermal stability. Thin films of the oxathiahydrazide also underwent facile thermal conversion. Independent syntheses of poly(phthaloyloxathiahydrazide) structures were achieved. (Author)


Descriptors :   HEAT RESISTANT PLASTICS , SYNTHETIC FIBERS , OXYGEN HETEROCYCLIC COMPOUNDS , THIAZOLES , DRAWING(FORMING) , SPINNING(INDUSTRIAL PROCESSES) , VISIBLE SPECTRA , ULTRAVIOLET SPECTRA , INFRARED SPECTRA , FLUORESCENCE , STABILITY , THERMAL PROPERTIES , SYNTHESIS(CHEMISTRY)


Distribution Statement : APPROVED FOR PUBLIC RELEASE