Rare; used for coating with rubber or (informal, chiefly US) for staring/gawking.
The technicians rubbered the cables to make them waterproof.
Les techniciens ont caoutchouté les câbles pour les rendre étanches.
Generally not comparable; used attributively to describe something made of or resembling rubber.
The rubber hose was flexible enough to reach all corners of the garden.
Le tuyau caoutchouteux était assez souple pour atteindre tous les coins du jardin.