Will machine intelligence ever achieve a level of sentience that will entitle them to protected 'human' rights?

Well lets start with the unwind experiment. You are awake ontop of the operating table. Teams of surgeons begin to systematically remove your body parts starting with your feet and working their way up, all the way piece by piece until they finally reach your head. Then they begin removing portions of your brain, until nothing is left. Throughout this whole time you are hooked up to life support and everything is very well maintained. At what point do you die? At what point do you stop feeling "you", and simply become a heap of disconnected parts, even though all those parts are still "alive"? Now we look at the current path of technology, which is being able to copy a person's brain patterns onto a computer. It is already underway, and successfull. Now they are doing head/brain transplants, cloning, memory reproduction. Pretty soon we will be moving "ourselves" onto digital counterparts, and it might even reach a state where nobody remembers having a physical body anymore. It might become another lost myth of evolution, something we speculate about. We will become the machines. I went on a tangent. To answer your question, it is possible IMO that yes machine intelligence will eventually become sentient, and therefore subject to the protections of "rights".