once the police catch up for him he will be going down
That isn't the case. When the police apprehend him there's no guarantee that he will be remanded in custody until he's tried for whatever offence(s) he's charged with and he could be on bail until the trial.
If he pleads not guilty it could be 9 months or more before he's tried. If convicted, only the judge can determine the sentence and, as another poster has said, he'll be out in half the time of whatever prison term he's given.
In the event that he goes to prison, he'll have access to solicitors and be given legal aid to establish his parental rights and pursue you for access to his child through the family courts and, if it established that he is the father. it's not inconceivable that you will be ordered to make the child available for prison visits.
If it should come to DNA testing, you may be held in contempt of court if you fail to provide samples.
With regard to restraining orders, injuctions are granted for a set period of time after which they lapse. Application can be made for renewal of a non-molestation order (which is what I am assuming you have) but any such application is unlikely to succeed unless he's been found to have been in breach of the earlier order.
You cannot seek a restraining order for an unborn child, nor can you seek an order to keep the father away from the child when it is born unless you can prove that he poses a significant risk to its wellbeing - as he may be safely banged up when the current order expires you'll be on a hiding to nothing in endeavouring to establish that he's a risk to you and/or the child.
Regardless of whatever the father of the child has done to you and regardess of whether or not he's made child maintenance payments, the family courts will not terminate his parental rights and are more than likely to grant a contact order. This may take the form of him intially engaging with the child in the supervised environment of a contact centre and, providing this goes well, extend to unsupervised contact, overnight stays, etc after which he could apply for a 50-50 childcare arrangements order.
How will you feel if the child is required to spend weekends, half of the school holidays, every other Christmas etc with its father, and how will this impact on you and on child itself?
Imo continuing this pregnancy could be the second worst decision you've ever made; the first being your decision to become involved with an abusive man and failing ditch him the minute he revealed his true nature.