Dry expansible sealant and baffle composition and product

A dry, initially non-tacky, expansible sealant and baffle component for sealing and providing an acoustic baffle for structure defining an area which is at least partially enclosed and that is subjected to a predetermined elevated temperature during a manufacturing operation, said component including:

• a quantity of an ethylene-.alpha.,.beta. ethylenically unsaturated carboxylic acid copolymer composition which has been at least partially neutralized with a metallic ion,
• said composition making up from about 30 to about 80 parts by weight of the component and having a melt index range of from about 0.2 to about 14;
• and
• a sufficient amount of a heat activated blowing agent to increase the volume of the component when the composition is raised to said elevated temperature,
• there being from about 0.1 to about 10 parts by weight of the blowing agent in the component;
• and
• from about 1 to about 10 parts by weight of a relatively low molecular weight resin tackifier constituent having the property of imparting tackiness to at least the outer surface of the component when the latter is raised to said elevated temperature and thereby expanded,
• said component being of a size and shape such that when the component is placed in said area and the area is thereafter subjected to said elevated temperature, the component expands to an extent that at least part of the outermost portion of the expanded component adhesively adheres to the surface of the structure defining said area as a result of the enhanced tackiness of the outer surface of the component at said elevated temperature, and the expanded component seals the area of the structure to present a baffle which substantially prevents infiltration of moisture and air attenuates annoying sounds.