Old tarp-- how do I repair it?

I have a very old tarp which I had made in an Idaho tarp factory (when I lived in Idaho long ago) for me in a special order long ago. [When I got it, I used it to cover the back of my pickup truck 'til I got a cap/shell for the back.] This tarp is NOT the cheaper kind found in hardware stores, i. e. the blue mesh ones used - say- by roofers to cover a roof, or to cover a boat, etc., etc. For some years now, I've been using the tarp as an awning. Due to the fact that for years I didn't roll up the tarp when I no longer needed it as an awning, cracks have developed along fold lines. [I know that folding was not good because the folding caused the cracks. I roll it up now.] One side is silver-gray (to face the sun) and the other side is black and doesn't seem to be rubberized-- the black side seems to be just some thin black coating of some sort. I continue to use the tarp as awning and light comes through the cracks. Even in these cracks, the fine mesh of the tarp shows through and is still intact with no tears. [It appears that the weave of the mesh is made of a fine poly-something thread.] Do you know of some product I could paint on the black side so that I'll still have my tarp for years to come? What do you think? What are the names of products that would probably or surely be useful to me? Where are they found?


Thanks