Polymeric materials that are blends of polymers having differing water solubility rates are disclosed. The blends may be incorporated into at least a portion of a medical devices such as the shafts of flushable urinary catheters to provide suitable catheter stiffness/flexibility and catheter disintegration in water receptacles such as toilets. The blended material may provide the substrate of the catheter shaft or may provide one or more layers of the catheter
