Self-strengthening polymer composites

Abstract

A composite material is provided including an elastomeric polymer matrix and undercooled liquid metallic core-shell particles disposed in the matrix, wherein the particles each have an outer shell and a liquid metallic material as a core contained within the outer shell. The outer shell is frangible such that the liquid metallic material is released from at least some of the particles in response to a mechanical load applied to the composite and solidifies in-situ in the polymer matrix. As a result, the composite material can be self-strengthening and self-healing and can be reconfigurable in shape at ambient temperature.

We claim: 
     
         1 . A composite material, comprising an elastomeric polymer matrix and undercooled liquid metallic core-shell particles disposed in the matrix, said particles each having an outer shell and a liquid metallic material as a core contained within the outer shell, which is frangible such that the liquid metallic material is released from at least some of the particles in response to a mechanical load applied to the composite and phase-changes in-situ in the polymer matrix. 
     
     
         2 . The composite material of  claim 1  wherein the released liquid metallic material is selected to solidify in-situ in the polymer matrix. 
     
     
         3 . The composite material of  claim 1  wherein the elastomeric polymer comprises a single polymer or a copolymer. 
     
     
         4 . The composite material of  claim 1  wherein the outer shell comprises an oxide shell. 
     
     
         5 . The composite material of  claim 1  wherein the outer shell is functionalized with an organic moiety. 
     
     
         6 . The composite material of  claim 1  wherein at least some of the particles are fused together by inter-particle solidification of the released liquid metallic material after the mechanical load is applied. 
     
     
         7 . A self-strengthening composite material, comprising an elastomeric polymer matrix and undercooled liquid metallic core-shell particles disposed in the matrix, said particles each having an outer shell and a liquid metallic material as a core contained within the outer shell, which is frangible such that the liquid metallic material is released from at least some of the particles in response to a mechanical load applied to the composite and solidifies within the polymer matrix to increase the strength of the composite. 
     
     
         8 . The composite material of  claim 7  wherein the elastomeric polymer comprises a single polymer or a copolymer. 
     
     
         9 . The composite material of  claim 7  wherein the outer shell comprises an oxide shell. 
     
     
         10 . The composite material of  claim 7  wherein the outer shell is functionalized with an organic moiety. 
     
     
         11 . A reconfigurable composite material, comprising an elastomeric polymer matrix and undercooled liquid metallic core-shell particles disposed in the matrix, said particles each having an outer shell and a liquid metallic material as a core contained within the outer shell, which is frangible such that the liquid metallic material is released from at least some of the particles in response to a mechanical load applied to the composite to change its shape and solidifies within the polymer matrix to retain the changed shape of the composite. 
     
     
         12 . The composite material of  claim 11  wherein the elastomeric polymer comprises a single or a copolymer. 
     
     
         13 . The composite material of  claim 11  wherein the outer shell comprises an oxide shell. 
     
     
         14 . The composite material of  claim 11  wherein the outer shell is functionalized with an organic moiety. 
     
     
         15 . A method of making a polymer composite, comprising mixing undercooled liquid metallic core-shell particles and an elastomeric polymer and curing the polymer to form the polymer composite. 
     
     
         16 . The method of  claim 15  wherein the elastomeric polymer comprises a single polymer or a copolymer. 
     
     
         17 . The method of  claim 15  wherein the outer shell comprises an oxide shell. 
     
     
         18 . The method of  claim 15  wherein the outer shell is functionalized with an organic moiety. 
     
     
         19 . A method of treating a polymer composite having an elastomeric polymer matrix and undercooled liquid metallic core-shell particles disposed in the matrix by applying a mechanical load to the composite in a manner to release liquid metallic material from at least some of the particles and solidifying the released liquid metallic material in-situ in the polymer matrix. 
     
     
         20 . The method of  claim 19  wherein the composite is treated by applying a tensile mechanical load or a compressive mechanical load to the composite.