Look at other options.
Longer and wider pads, 40" wide or more, don't slip as much, I think. I certainly haven't ever had a slippage problem with my 60 X 40" Oware pad. Gossamer offers a similar one.
Besides the benefit of little to no slipping, the Oware and Gossamer pads are significantly lighter and cheaper while, IMO, offering the same or superior insulation.
But the Oware is bulky to pack...