Expandable magnetic sealant

• US 4,769,166 A
• Filed: 06/01/1987
• Issued: 09/06/1988
• Est. Priority Date: 06/01/1987
• Status: Expired due to Term

• Current Assignee: Permacel Kansas City, Inc. (Nitto Denko Corporation)
• Original Assignee: United Technologies Automotive, Inc. (Lear Corporation)
• Inventors: Harrison, Bruce
• Primary Examiner(s): Capella, Steven
• Application Number:
  US07/056,163
• Time in Patent Office: 463 Days
• Field of Search: 252/62.54, 277/80
• US Class Current: 252/62.54
• CPC Class Codes: C08J 2353/02 of vinyl aromatic monomers and conjugated dienes
• CPC Class Codes: C08J 9/0066 Use of inorganic compounding ingredients
• CPC Class Codes: F16J 15/14 by means of granular or plastic material, or fluid
• CPC Class Codes: F16J 15/43 kept in sealing position by magnetic force
• CPC Class Codes: H01F 1/375 Flexible bodies
• CPC Class Codes: H01F 41/16 the magnetic material being applied in the form of particles, e.g. by serigraphy , to form thick magnetic films or precursors therefor H01F41/18 -H01F41/24 take precedence
• CPC Class Codes: Y10S 277/933 Chemical reaction or physical change of state
• CPC Class Codes: Y10S 277/944 Elastomer or plastic

Abstract

Disclosed is a novel, magnetic sealant comprising a styrene blocked copolymer, a solubilizing agent, magnetic particles and a blowing agent which will, upon exposure to temperature, will cause the sealant to melt and be drawn toward the magnetically attractive substrate and will also foam, thereby increasing in dimension to fill irregular gap.

Claims

1. A magnetic sealant composition comprising:

block copolymers of styrene and an elastomeric block,

a solubilizing agent, magnetically charged particles and a blowing agent, wherein the sealant flows and foam upon heating to above the melt temperature of the sealant and the activation temperature of the blowing agent.

2. The composition of claim 1 wherein the solubilizing agent is present in concentrations from about 20 percent by weight to about 50 percent by weight of the styrene block copolymer.

3. The composition of claim 2 wherein the magnetic particles are present at concentrations of about 60 percent to about 80 percent by weight of the sealant.

5. The composition of claim 1 wherein the copolymer has a tensile strength of about 2,000 psi at 75°

F. (23.9°

C.).

4. A magnetic sealant composition comprising:

block copolymers of styrene and an elastomeric block,

a solubilizing agent, magnetically charged particles and a blowing agent, and an epoxy resin and an epoxy resin curing agent, wherein the resulting sealant flows and foams upon heating to a temperature above the melt temperature of the sealant and the activation temperature of the blowing agent and at the same temperature, will cure the epoxy resin subsequent to the sealant having expanded.

6. A method for sealing a gap between two or more meeting surfaces of which at least one of the surfaces is ferrometallic comprising placing a hot melt magnetic foamable sealant on at least one of the ferrometallic surfaces, heating the magnetic sealant to a sufficient temperature to cause the sealant to melt and activate the blowing agent thereby causing the sealant to flow and expand to seal the gap.