Use of shear to incorporate tilt into the microstructure of reversible gecko-inspired adhesives

Patent metadata

Field	Value
Publication number	US-9546308-B2
Application number	US-201314373278-A
Country	US
Kind code	B2
Filing date	Jan 22, 2013
Priority date	Jan 19, 2012
Publication date	Jan 17, 2017
Grant date	Jan 17, 2017

Abstract

The present invention relates to an easy, scalable method, relying on conventional and unconventional techniques, to incorporate tilt in the fabrication of synthetic polymer-based dry adhesives mimicking the gecko adhesive system. These dry, reversible adhesives demonstrate anisotropic adhesion properties, providing strong adhesion and friction forces when actuated in the gripping direction and an initial repulsive normal force and negligible friction when actuated in the releasing direction.

First claim

What is claimed is:

1. A method for fabricating an adhesive comprising:
a step for forming a patterned mold;
a step for forming an inverse replica of said patterned mold; said inverse replica forming step comprising:
(i) a step for applying a first polymer to said patterned mold,
(ii) a step for allowing said first polymer to partially cure,
(iii) a step for removing said partially-cured first polymer from said patterned mold,
(iv) a step for shearing said partially-cured first polymer,
(v) a step for allowing said sheared partially-cured first polymer to fully cure; and
a step for forming a final adhesive using said sheared inverse replica of said patterned mold.

2. The method of claim 1 , wherein forming said patterned mold comprises:
a step for forming a two-layer etch mask to a nonreactive base.

3. The method of claim 2 , wherein said nonreactive base comprises a silicon wafer.

4. The method of claim 2 , wherein said two-layer etch mask comprises a first layer patterned with rectangular structures.

5. The method of claim 4 , wherein said two-layer etch mask further comprises a second layer patterned with cylindrical structures.

6. The method of claim 4 , wherein said two-layer etch mask further comprises a second layer patterned with structures in the shape of triangular prisms.

7. The method of claim 1 , wherein said inverse replica is comprised of polydimethylsiloxane.

8. The method of claim 1 , wherein said final adhesive is comprised of polyurethane.

Assignees

• The Administrators Of The Tulane Educational Fund

Inventors

• Pesika Noshir
• Jin Keijia

Classifications

• C09J2201/626

  Chemistry & Metallurgy · mapped topic

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title

• B81C1/00103

  Structures having a predefined profile, e.g. sloped or rounded grooves · CPC title

• B81B2203/0361

  Tips, pillars · CPC title

• C09J7/00

  Adhesives in the form of films or foils · CPC title