The scientists at lawrence livermore lab have been able to produce 6 new, synthetic elements. why isn't there yet a practical use for these elements?

There is not any practical use yet for these elements since the atoms are not stable so they decay almost immediately. Researchers have artificially created heavier elements, but those elements have had briefer lifetimes, time that it takes for unsteady elements to deteriorate by processes like spontaneous fission of the nucleus.