Changing physics properties of a gameobject through code.

I have a sphere in this little game i'm building, and sometimes its a bouncy ball and sometimes its a metal ball. The bouncy ball works perfect but when I change to metal ball and ball is in the air it bounces too. I have the physics materials set. I also put a physics material on platform that has no bouciness. The only thing that works is a surface effector that doesn't use bounce. I dont want to change the bool on all surface effectors and I don't want surface effectors on everything. Here is a piece of my code, I change properties with a button.

P.S. This is a 2D game.

 public void HeavyBall()
 {
     surEffect.useBounce = false;
     rend.sharedMaterial = solid;
     col.sharedMaterial = heavyBall;
     rigidBody.gravityScale = 3f;
     rigidBody.drag = 0.2f;
     rigidBody.angularDrag = 0.5f;
 }

 public void RubberMaterial()
 {
     surEffect.useBounce = true;
     rend.sharedMaterial = rubber;
     col.sharedMaterial = bouncingRubber;
     rigidBody.gravityScale = 1f;
     rigidBody.drag = 0f;
     rigidBody.angularDrag = 0.05f;
     if(isOnGround)
     {
         rigidBody.velocity = new Vector2( 0f, 7.5f);
     }
 }