When I was little I remember sitting at the top of the stairs peeping through the bannisters while my Dad screamed at my Mum and smacked her glasses off her face etc. Mum had a big dent in her forehead from where he'd punched her in the face earlier in the marriage. Sometimes they wouldn't speak for six weeks at a time and I'd have to pass messages back and forth.
I know so many people grow up wishing their parents hadn't seperated, but I grew up desperately wishing they had. Some people just aren't right for each other, and the fact that he's like that around your daughter suggests he's out of control and will get increasingly violent. You don't sound surprised by his behaviour, I take it he's been like this before?
I know it's horrible when you post a thread like this and everyone says "leave him!" and you know it'd be so hard to do, and some part of you still loves him etc but you need to do what's right for your dd, because if he hits you so easily, when she starts talking back in a few years, he'll start with her.
Go to family/friends with your baby and leave him to think about what he's done. Sod the toilet, let it be his problem! I really hope this is the last episode like this you'll have to endure, poor thing.