What materials bounce cowhide or vulcanized rubber most?

[grey16]

I am trying to find out what material that cowhide or vulcanized rubber will bounce off the most? (High school student working on a patent, so really not too experienced with materials engineering.)

 

[Simon Bridge]

Welcome to PF;
The subject is too broad ... you just have to test the materials you are interested in.
For what purpose is a high school student working on a patent?

As a general rule, the less a material deforms when struck the more energy is available for the bounce ... so soft cowhide does not bounce well, and it bounces badly off another soft cowhide, or a very flexible sheet of rubber. But construction is important too - i.e. a trampoline deforms a lot but you bounce higher off that than from the ground because you are actually bouncing off the steel springs ... even so, rubber balls perform poorly off a trampoline mat compared with a concrete floor.
A cowhide ball will bounce better from any surface than a flat sheet and you can make springs out of hide, and/or treat it to be stiff. See what I mean?

The engineering term you will be looking for is "coefficient of restitution".