People can, and do change, every day.
When we want to bring about a change in the behaviour of others, it's sometimes necessary to change our own.
When he's being verbally abuse, don't be tempted to fight fire with fire otherwise what could relatively quickly be over done with, may turn into a prolonged slanging match.
If he says anything that you feel is inappropriate or abusive, don't reward him with your attention and simply walk away.
Insofar as your dc are concerned, if he starts shouting, distract them by saying 'come and see x, y, or z,' in another room, the garden, etc and walk away from him.
If he follows, tell him that he is behaving unreaonably and then simply sit silently with the dc until he's finished ranting. When his ranting is over, don't acknowledge what he's done/said in any way. Simply carry on conversing/playing with the dc as if nothing untoward has happened.
Don't be tempted to turn it into some kind of game 'there goes daddy, off on one again' etc a) because it will feed his fire and b) because it will belittle him in the same way as he's belittling you/the dc.
It'll take a lot of self-control on your part but, the more you can keep your cool, the more unreasonable he will begin to sound to himself.
In many ways changing an adult's unacceptable behaviour is not dissimilar to altering that of a child, but in this case you need to withdraw from his bad behaviour and positively reinforce the message when he controls himself.
You may not like him very much at the moment, but try to find something to praise him for - even if it's just taking the garbage out. Or have a bottle of wine and/or snacks waiting for him when he comes home tonight, and praise him by telling him how much you appreciated him listening to, and taking on board, your concerns this afternoon - but don't be tempted to rehash your conversation or add more to what you've aready said.
Think star chart and build in some rewards for both of you. Although there are disadvantages when both parties are largely at home all day, treat yourselves once a week either to lunch out or to a special lunch a deux in the comfort of your own home/garden and use this time to talk about anything and everything except your relationship/his behaviour/the dc.
If he achieves a day of non-abusive behaviour, make him feel good about himself in word or deed. If he hasn't controlled his tongue, tell him calmly that you are disappointed that he let himself down by saying or doing x, y, or z.
You've already found that I have been very cool with him has got you a result; Keep up the good work!! And, when you feel that he has taken on board your concerns and is making a serious attempt to change his behaviour, show him how hot you can be.
Of course you shouldn't have to do any of the above - and you don't have to unless you want to have a last ditch attempt at saving your marriage.