ADVANCED ORDERED POLYMER/GLASS MICROCOMPOSITES

ORDERED POLYMER MATERIALS PROCESSED FROM LIQUID CRYSTALLINE SOLUTIONS CAN BE USED WITH GLASS PROCESSED BY THE SOL-GEL METHOD TO PRODUCE A COMPOSITE WITH HOMOGENEITY ON A VERY SMALL SCALE. SUCH A "MICROCOMPOSITE" MATERIAL ROD-LIKE POLYMER PBT (POLY PHENYLENE BENZOBISTHIAZOLE) AND GLASS, SUCH AS SILICA, OFFERS SOME POTENTIAL ADVANTAGES. PBT WOULD PROVIDE HIGH TENSILE STRENGTH, STIFFNESS, TOUGHNESS, AND THERMAL RESISTANCE COMMON TO THIS CLASS OF POLYMERS. GLASS WOULD PROVIDE EXCELLENT COMPRESSIVE STRENGTH, LOW PERMEABILITY, CREEP RESISTANCE AND OF COURSE HIGH TEMPERATURE CAPABILITY. BOTH MATERIALS HAVE EXCELLENT DIMENSIONAL STABILITY AND GOOD DIELECTRIC PROPERTIES. PBT FILMS HAVE BEEN PROCESSED FROM SOLUTIONS, LEAVING AN OPEN MICROSTRUCTURE IN THE WET SWOLLEN STATE. GLASS, SUCH AS SILICA, CAN BE PRECIPITATED INTO THE PBT NETWORK BY SOL-GEL METHODS. WE PROPOSE TO FURTHER DEVELOP THESE METHODS TO FORM HIGH STRENGTH, HIGH STIFFNESS PBT/GLASS MICROCOMPOSITE FILMS. FURTHER DEVELOPMENT WILL CONCENTRATE ON USING THE PBT/GLASS FILMS AS PREFORMS FOR LARGE STRUCTURES. THE PROPOSED PROGRAM WILL EVALUATE THE FEASIBILITY OF ACHIEVING EXCELLENT MATERIAL PROPERTIES BY SUCH PROCESSES.