I had to remove my uncle from my friend list for almost that exact reason.

He's very closed-minded and opinionated and while that's acceptable in some cases, he did nothing but post hateful, negative, and mis-informed things about whatever was going on in he news. One of his friends actually jumped on me and insulted me after I pointed out to them that they had been mis-informed about what they were ranting about.

Since then I realized that everyone on Facebook really just should keep their dumbest thoughts to themselves. I don't get notifications anymore from over half of my "friends" just because I can't handle the vast amount of stupid posts they put up.