Devices, compositions, and methods incorporating adhesives whose performance is enhanced by organophilic clay constituents
Incorporating organophilic clay into hot melt adhesive compositions, particularly those comprising semi-crystalline, thermoplastic polymers, greatly improves the adhesive properties in many respects. Some of these improvements are particularly beneficial to the specific use of hot melt adhesives filled with electrically conductive particles for use as electrically conductive adhesives.
1. An electrically conductive adhesive composition comprising:
a) a polymeric adhesive component comprising a semicrystalline thermoplastic polymer which comprises at least one polyether chain segment and at least one polyamide chain segment;
b) an electrically conductive filler incorporated into the adhesive component; and
c) a clay component incorporated into the adhesive component, said clay component comprising an organophilic clay.
2. The electrically conductive adhesive composition of claim 1 , wherein the electrically conductive filler comprises a plurality of electrically conductive particles.
3. The electrically conductive adhesive composition of claim 1 , wherein the electrically conductive filler comprises an electrically conductive scrim.
4. The electrically conductive adhesive composition of claim 1 , wherein the composition comprises 1 to 80 volume percent of the filler based upon the total volume of the composition.
5. The electrically conductive adhesive composition of claim 1 , wherein the adhesive component further comprises at least one curable material selected from a monomer, an oligomer, a polymer, and combinations thereof.
6. The electrically conductive adhesive composition of claim 1 , wherein the thermoplastic polymer has a weight average molecular weight in the range of 1000 to 1,000,000.
7. The electrically conductive adhesive composition of claim 1 , further comprising a tackifier.
8. The electrically conductive adhesive composition of claim 1 , wherein the clay component comprises an organophilic smectite clay.
9. The electrically conductive adhesive composition of claim 1 , wherein the composition comprises from about 1 to about 25 weight percent of the organophilic clay based upon the total weight of the composition.
10. An anisotropically, electrically conductive adhesive comprising:
a) a polymeric adhesive component comprising a semicrystalline thermoplastic polymer which comprises at least one polyether chain segment and at least one polyamide chain segment;
b) a plurality of electrically conductive particles incorporated into the adhesive component; and
c) a clay component incorporated into the adhesive component, said clay component comprising an organophilic clay.
11. An electrically conductive adhesive composition comprising:
a) a polymeric adhesive component;
b) an electrically conductive filler incorporated into the adhesive component, wherein the electrically conductive filler comprises an electrically conductive scrim; and
c) a clay component incorporated into the adhesive component, said clay component comprising an organophilic clay.
12. The electrically conductive adhesive composition of claim 11 , wherein the adhesive component comprises a semi-crystalline, thermoplastic polymer.
13. The electrically conductive adhesive composition of claim 11 , wherein the adhesive component further comprises at least one curable material selected from a monomer, an oligomer, a polymer, and combinations thereof.
14. The electrically conductive adhesive composition of claim 11 , wherein the thermoplastic polymer has a weight average molecular weight in the range of 1000 to 1,000,000.
15. The electrically conductive adhesive composition of claim 11 , wherein the thermoplastic polymer is hydrophobic.
16. The electrically conductive adhesive composition of claim 11 , wherein the thermoplastic polymer is a block copolymer and comprises a hydrophobic block.
17. The electrically conductive adhesive composition of claim 11 , wherein the thermoplastic polymer comprises at least one polyether chain segment and at least one polyamide chain segment.
18. The electrically conductive adhesive composition of claim 11 , further comprising a tackifier.
19. The electrically conductive adhesive composition of claim 11 , wherein the clay component comprises an organophilic smectitc clay.
20. The electrically conductive adhesive composition of claim 11 , wherein the composition comprises from about 1 to about 25 weight percent of the organophilic clay based upon the total weight of the composition.