Composition having sealing and sound dampening properties and methods related thereto

A multilayer composite comprising a weldable primer layer formed from a weldable primer composition, and a second layer having improved sealing and sound dampening properties formed from a second composition over at least a portion of the weldable primer layer, the second composition comprising:

• (a) one or more polyepoxides comprising at least two epoxide groups per molecule;
• (b) a thermoplastic polyester polymer;
• (c) a curing agent adapted to react with the polyepoxide (a);
• (d) inorganic particles having an oil absorption value of less than 70 as determined in accordance with ASTM D 281-95;
• and
• (e) inorganic microparticies different from the inorganic particles (d), the inorganic microparticles having an average particle size prior to incorporation into the composition ranging from 0.5 to 200 microns.

A coated metallic substrate comprising:

• a metallic substrate, and a composition having sealing and sound dampening properties over at least a portion of the substrate, said composition comprising:
• (a) one or more polyepoxides comprising at least two epoxide groups per molecule;
• (b) a thermoplastic polyester polymer;
• (c) a curing agent adapted to react with the polyepoxides (a);
• (d) inorganic particles having an oil absorption value of less than 70 as determined in accordance with ASTM D 281-95;
• and
• (e) inorganic microparticles different from the inorganic particles (d), the inorganic microparticles having an average particle size prior to incorporation into the composition ranging from 0.5 to 200 microns.

A coated metallic substrate comprising:

• a metallic substrate;
• a weldable primer layer formed from a weldable primer composition deposited over at least a portion of the substrate;
• and
• a second layer formed from a second composition having sealing and sound dampening properties deposited over at least a portion of the weldable primer layer, the second composition comprising:
• (a) one or more polyepoxides comprising at least two epoxide groups per molecule;
• (b) a thermoplastic polyester polymer;
• (c) a curing agent adapted to react with the polyepoxides (a);
• (d) inorganic particles having an oil absorption of less than 70;
• and
• (e) inorganic microparticles different from the inorganic particles (d),
• the inorganic microparticles having an average particle size prior to incorporation into the composition ranging from 0.5 to 200 microns.

A method for forming a coating having sealing and sound dampening properties on a metallic substrate comprising the steps of:

• (a) providing a metallic substrate having two major surfaces;
• (b) applying a composition to at least a portion of one of the major surfaces of the substrate, said composition comprising:
• (1) one or more polyepoxides comprising at least two epoxide groups per molecule;
• (2) a thermoplastic polyester polymer;
• (3) a curing agent adapted to react with the polyepoxides (1);
• (4) inorganic particles having an oil absorption value of less than 70 as determined in accordance with ASTM D 281-95;
• and
• (5) inorganic microparticles different from the inorganic particles (4), the inorganic microparticles having an average particle size prior to incorporation into the composition ranging from 0.5 to 200 microns;
• and
• (c) curing the applied composition,
• wherein the coated substrate of step (c) has a sound dampening value greater than 0.030 Oberst dissipation factor as measured at 200 Hz at 25° C. in accordance with ASTM E-756-98.

In a composition having sealing and sound dampening properties comprising:

• (a) one or more polyepoxides comprising at least two epoxide groups;
• (b) a thermoplastic polyester polymer;
• (c) a curing agent adapted to react with the polyepoxide (a);
• and
• (d) inorganic particles having an oil absorption value of less than 70 as determined in accordance with ASTM D 281-95,
• the improvement comprising the inclusion in the composition of inorganic microparticles different from the inorganic particles (d) in an amount sufficient to provide corrosion resistance properties as measured in accordance with Chrysler Test Method LP-463PB-10-01 which are superior to the corrosion resistance properties of the same composition which does not contain said inorganic microparticles, the inorganic microparticles having an average particle size prior to incorporation into the composition ranging from 0.5 to 200 microns.