Abstract: Hot melt compositions are disclosed from which foamed products having a fine and uniform void structure therein can be obtained. The compositions include a thermoplastic polymer preferably an elastomer such as a styrene-butadiene block copolymer, and a small amount of a salt of a sulfonated styrene polymer. Plasticizing processing aids, tackifying agents and antioxidants can be included in the compositions, as well as in addition surfactants such as dodecylbenzene sulfonate. The composition can be mixed with gaseous blowing agents by suitable means and dispensed to produce foamed products suited for example as sealants in closures for containers.