I daresay you'll find places that will take it, but the Irish currency is now the Euro. You don't see prices in both any more. If you can find shops that will take it, the rate will be worse than you can get Euros for here, I'd just change it before leaving.
It is accepted in some shops, especially within about a mile of the border, but not as a rule, even though (as far as I know) it was never the currency there