Phosphor bronze tends to be used nowadays because it gives a louder, warmer tone. Nickel wound strings were often used in the old days and some players still swear by them. No theoretical reason why you couldn't use slinkys...
...providing it is possible to set your acoustic up for them.
There's less tension in nickel wound strings (or nickel plated steel wound, to be more accurate) than in phosphor bronze and its relatives. You may find it difficult to loosen the truss rod enough to accomodate them (otherwise they'll be stretched flat on the frets due to the back-bow you're likely to get).
You might also find the intonation is all over the place... not quite as simple a matter to adjust intonation on an acoustic.