Chairman Darragh MacAnthony confirmed the signings of Tunnicliffe and Wootton on his Twitter page.
MacAnthony tweeted: "Gaffer just told me two united lads signed on loan - Tunnicliffe & Wootton signed up. And so it starts!"
Tunnicliffe is a midfielder and Wootton is a defender who had a spell on loan at Tranmere last season.
Tunnicliffe signs immediately on a six-month loan while Wootton will sign at the end of July. Both players will go on the club's Portuguese training camp from Sunday.