If your looking to poly as a way to "fix" a crippled relationship, you're lighting a delayed fuse linked to the supports of the relationship.
If you're looking at it as something to explore as a way of broadening the relationship, it has the same chance of working as any relationship.
I'd be sure to discuss this at length with your current boyfriend and give him EVERY opportunity to object if he feels the need to. Be aware though, the truly non-jealous person is a very rare person. Jealousy isnt bad in and of itself, its how you deal with it that matters.