A poromeric sheet material is provided with deporomerized areas selectively disposed at points where better mechanical strength is desired and where in addition better hydrostatic resistance is desired. Better mechanical strength means better abrasion resistance, better puncture resistance, better flex life. Better hydrostatic resistance means resistance to wetting-through, resistance to bibulousness, resistance to the passage of water-borne soiling agents. The deporomerized areas of the poromeric sheet material preferably are disposed in the areas where, for instance, a shoe upper made from the material is joined to the shoe sole, where the greatest flex-life is desired and where the greater waterproofness is desired. Other poromeric articles such as wearing apparel, upholstery and the like may be similarly provided with deporomerized areas selectively disposed in areas where better mechanical properties and better waterproofness may be desired.
