It is possible to communicate an IRC 5 ABB Robot with master output devicenet with a Rslogix5 PLC in networked with an driver ethernet device using converter ethernet / IP to DeviceNet?

Yes, No ,& Maybe. If you are looking for a straight AB formula I don't think so without using a CLX as a bridge. From what I remember about the PLC5 DeviceNet card it has to be the Master. I have only set up 1 of them 2 years ago with 1 node in a class so I can't swear by it.
You may find a Anybus card tha will fit in the IRB controller. and talk PLC5 ethernet.
I did several jobs with S4C+ and RIO cards. That may be an option.
Does the controller use DeviceNet or CanBus? Again going from memory all the native ABB I/O was on CanBus.

Look at RealTimeAutomation They have a bridge that will do it. I have a MLX1100 being a DeviNet master to 3 scales.

thanks

What happened with it? What did you decide to do?