First OP if your friends are all mutual, please don't confide in them about this in case it gets back to him.
You need professional help. You can call the National Helpline: 0808 2000 247 or look for your local DV organisation by doing an online search for 'Domestic Abuse Help Clapham' or wherever you live. Your council website will also have DV orgs listed.
Next time he kicks off, dial 999. Work out an emergency route out of the house if he does become physically aggressive and try to assault you. His behaviour is escalating OP, so he will eventually go for you. Keep arguments away from the kitchen and do not get trapped in somewhere like the bathroom, lots of hard surfaces and nowhere to go if he gets in. Pack a grab bag of stuff for you and the baby.
If you can't phone then you can live chat the national helpline, you can email a local org or you can go to a pharmacy like the Morrisons pharmacy, Superdrug, Boots and ask for the consultation room where you can use their phone to contact DV organisations.
Next time there is an outburst, you need to dial 999 and get the police involved. Download the Brightsky app where you can record audio and video and start to document his behaviour.
Once the police have arrested him and hopefully, taken him away, dial: 0800 970 2070 (Press Option 1) this is a 24hr number, so any time of day of night. It's the number for the NCDV who can advise on a Non Molestation Order to keep him away from you and an Occupation Order to keep him out of the house.