Sure, it could be. Do a test on something you don't care about and give it plenty of time to cure between coats, then report back.
I've started using Stynylrez and it's love at first sight. It seems to be thin, tough, adheres well and actually comes up to a medium sort of level of polish with a paper towel rub.
Other modelers report mixed results with Vallejo primer adhering to plastic. I cannot vouch for that one way or the other since I don't use Vallejo paint. So if you could get your particular witches brew there to work, please report.
I'm currently testing Alclad over Stynylrez, but that wasn't your question.
Bill