Polymer microlattice structures with multifunctional coatings for substrate bonding
In some variations, a polymer-based microlattice structure includes a plurality of intersecting micro-truss structural elements each comprising a thermoset first polymer, and a continuous coating layer (with a second polymer) that substantially encapsulates each of the micro-truss structural elements, wherein the second polymer in the continuous coating layer bonds the thermoset first polymer to a substrate. The micro-truss structural elements preferably are architecturally ordered and the coating layer is uniformly distributed within the microlattice structure. The polymer coating layer may be present over the entire microlattice surface area, thereby increasing bond area to improve toughness. The microlattice structure may also have higher glass-transition temperature and chemical resistance, compared to a microlattice structure without the coating layer. Methods of forming a polymer-based microlattice structure are also disclosed.
1. A polymer-based microlattice structure comprising:
(a) a first substrate layer;
(b) a plurality of intersecting micro-truss structural elements each comprising a thermoset first polymer; and
(c) a continuous coating layer that substantially encapsulates each of said micro-truss structural elements, wherein said coating layer comprises a second polymer,
wherein said second polymer in said continuous coating layer bonds said first substrate layer to said thermoset first polymer, and
wherein said microlattice structure does not contain a secondary adhesive material between said micro-truss structural elements and said first substrate layer.
2. The microlattice structure of claim 1 , wherein said micro-truss structural elements are architecturally ordered.
3. The microlattice structure of claim 1 , wherein said coating layer is uniformly distributed within said microlattice structure.
4. The microlattice structure of claim 1 , wherein said coating layer is bonded with said first substrate layer to form a coating/substrate bond area, wherein said coating layer substantially encapsulates said micro-truss structural elements to form a coating/micro-truss contact area, and wherein said coating/substrate bond area is less than said coating/micro-truss contact area.
5. The microlattice structure of claim 4 , wherein the ratio of said coating/substrate bond area to said coating/micro-truss contact area is about 0.2 or less.
6. The microlattice structure of claim 1 , wherein the ratio of average thickness of said coating layer to average micro-truss structural element effective diameter is about 0.0001 to about 5.
7. The microlattice structure of claim 1 , wherein said second polymer in said continuous coating layer chemically bonds said first substrate layer to said thermoset first polymer.
8. The microlattice structure of claim 1 , wherein said second polymer in said continuous coating layer physically bonds said first substrate layer to said thermoset first polymer.
9. The microlattice structure of claim 1 , wherein said microlattice structure does not contain mechanical joints between said micro-truss structural elements and said first substrate layer.
10. The microlattice structure of claim 1 , said microlattice structure further comprising a second substrate layer that is disposed distally from said first substrate layer, wherein said second polymer in said continuous coating layer chemically and/or physically bonds said second substrate layer to said thermoset first polymer.
11. The microlattice structure of claim 1 , wherein said first substrate layer comprises a thermoplastic material.
12. The microlattice structure of claim 1 , wherein said first substrate layer comprises a non-thermoplastic material selected from the group consisting of a thermoset polymer, a metal, a ceramic, and combinations or composites thereof.
13. The microlattice structure of claim 1 , wherein said second polymer is a thermoset polymer.
14. The microlattice structure of claim 1 , wherein said second polymer is a thermoplastic polymer.
15. The microlattice structure of claim 1 , wherein said second polymer is a mixture of a thermoset polymer and a thermoplastic polymer.
16. A polymer-based microlattice structure comprising:
(a) a first substrate layer;
(b) a plurality of intersecting micro-truss structural elements each comprising a thermoset first polymer; and
(c) a continuous coating layer that substantially encapsulates each of said micro-truss structural elements, wherein said coating layer comprises a second polymer,
wherein said second polymer in said continuous coating layer bonds said first substrate layer to said thermoset first polymer, and wherein said coating layer further contains magnetically active particles or domains.