Are the words a husband says to his wife while he is angry, intending to threaten or reconcile—not intending divorce—binding?

What you have mentioned falls under the category of waswasa (whispering of Satan/obsessive thoughts), and no legal ruling is entailed by it. Merely threatening with these words does not make the kinayah (ambiguous divorce utterance) a divorce. Divorce by kinayah does not occur unless there is an intention to effect it. The fact that you did not intend to separate from your wife with these words makes them laghw (idle talk) with no effect. Certainty is not dispelled by doubt, and the cure for waswas is to disregard it and pay no attention to it.