I know you can block players through the PSN network but I don't believe that has anything to do with being matched with them in games. However, I had heard conflicting information from Sony on this.
All I can say is that I always block players who I had bad experiences with in RDO (after reporting them) and never had run-ins with them again after that. Now, whether that means the block worked or it was simply chance, I don't know.
Other than that, there is no way to prevent being matched with the same people again that I know of. The PSN block will also ensure that these people can't follow you, be part of your communities, send you msgs, etc. so depending on your situation, that could still help.