What is the formula (chemical) of slime/flubber?

I did a lab on creating flubber, but I need to find the chemical reaction that occured. I added PVA (polyvinyl alcohol) with Borax (sodium tetraborate) and water. I know that it goes through a cross-link reaction, but I don't know what the formula for flubber is. (i.e. PVA + Na2B4O7•10H2O -> ???; and do I add water in this equation?)