FABRICATION OF NON-SPHERICAL PARTICULATES

PARTICULATES OF VARIOUS SHAPES ARE USEFUL IN MANY AREAS OF INDUSTRY. SPECIFICALLY, SUCH PARTICULATES ARE NEEDED TO SIMULATE PLANKTONS IN OCEAN FOR USE IN WATER TUNNEL TESTS. WE PROPOSED TO FABRICATE THE NON-SPHERICAL PARTICULATES BY TWO METHODS: PHOTOLITHOGRAPHIC TECHNIQUES WILL BE USED TO PRODUCE PARTICULATES OF ROD, DISK, STAR, HEXAGONAL OR OTHER DISTINCT GEOMETRICAL SHAPES, AND CHEMICAL TECHNIQUES WILL BE USED TO PREPARE "BRISTLE BRUSH" SHAPED PARTICULATES. IN THE PHOTOLITHOGRAPHIC METHOD, A PHOTOMASK WITH PARTICULATE PATTERNS OF PROPER DIMENSION AND CONFIGURATION WILL BE FABRICATED AND BY USING PHOTORESIST AND PHOTOPROCESSES, AN ARRAY OF PARTICULATES WILL BE REPRODUCED ON AN APPROPRIATE SUBSTRATE. THESE PARTICLES CAN BE COLLECTED FROM THE SUBSTRATE BY ETCHING OR BY ULTRASONICATION. TO PRODUCE BRISTLE BRUSH PARTICULATES, THE IONIC INTERATION FORCES WILL BE USED. IF THE CENTER BODY OF THE BRISTLE BRUSH IS CHEMICALLY TREATED TO BE CATIONIC IN NATURE AND FIBER IS ANIONICALLY CHARGED, SIMPLE MIXING OF THESE TWO IONIC SPECIES WILL RESULT IN HAIRY PARTICULATES.