is it possible to go from IPA to n-propylOH?
It isn't impossible (e.g. iPrOH-->propene-->n-PrBr-->n-PrOH), but there is no practical way. I'm sure you thought of that, but why not buy n-PrOH? Cheap and not watched.
lots of 99+ IPA lying about. gallons.
too broke to pay attention. (but thanks)