Why does my husband take off his wedding ring when we argue?

We've been married for 7 years -- second marriage for both. He has 2 kids, I have 3, and they are all teenagers, ranging from 15 (my triplets) to 17, 18 (his daughters.) We also have a 6 year old together.

We had great communication before we married (I thought), but after that everything went to crap. His oldest daughter is very troubled and has issues with her mom, which she has transferred to me (saw that one coming.) But that's another question for another day.

Of course, it can be stressful with 5 teenagers in the house. But what makes matters worse is the way my husband handles disagreements. Everything is his way or the highway. If we have a heated argument about something and don't get it resolved (which is 99% of the time), he will take off his wedding ring and give me the silent treatment for days. Then, inexplicably, he'll put it back on and resume talking to me. I have ignored these immature attempts to get my goat until this last time, when I called him on his behavior and pointed out how confused his employees must be, not knowing from one day if he's married, divorced, remarried, or divorced again! (He is GM/partner of a car dealership.)

He is extremely smart, funny, perceptive (when it comes to other people), can fix anything, is a great provider and has all sorts of wonderful qualities. Yet his inflexability, needing to be the "boss" at home (can't leave it at work), and childish manipulations make me wonder. He is also a name-caller, something I abhor. I don't understand how someone so accomplished and intelligent can resort to such behaviors when frustrated. He is otherwise a good man.

Guys, help me out here.