The 19-year-old's agreement, which will last for 93 days, also includes a 24-hour recall clause after the first month.
Poleon scored twice on loan at Bury earlier in the season, whilst he was on target for Leeds in their victory over Nottingham Forest in September.
Manager Danny Wilson admitted he had enquired about his services in the January transfer window and is pleased to have finally landed his target.
"He is young, raw and unpredictable, but he is quick and offers pace defenders won't like to defend against," he told the club's official website.
"He can offer us a lot both in terms of starting games and also as an impact substitution from the bench. We need that extra striker and if we are to be successful we need as many strikers available as possible."