To help slow down damage, I recommend a UV protectant such as UV Tech. It's designed to protect, repair, rejuvenate, and "re-plasticize" a variety of materials including latex (fiberglass, rubber, nylon, plastics). You can use it for dive gear, camping gear, all sorts of stuff. I use it on my latex and plastic props before I put them out, and again before I store them away. I have some pretty old latex props that still look good, so I do think it helps. I use it both on the decorations that go outside in the sunshine, and the stuff that decorates the inside of the house.
Good luck with your repairs!