Microwave driven diffusion of dielectric nano- and micro-particles into organic polymers

Abstract

A method of doping a substrate with dielectric dopant particles. The substrate, comprising an organic polymer, is exposed to a first layer comprising a first plurality of dielectric dopant particles. The organic polymer has a thermal conductivity that is less than 5 Wm −1 K −1 and a lossiness that is less than a lossiness of the first plurality of dielectric dopant particles. The substrate and first layer are irradiated by an energy source operating at an operating frequency. During the irradiation, the first plurality of dielectric dopant particles of the first layer diffuses into the organic polymer of the substrate. Irradiation continues for a first desired time to achieve a first desired depth of penetration of the first plurality of dielectric dopant particles into the organic polymer.

What is claimed is: 
     
         1 . A method of doping a substrate with dielectric dopant particles, the method comprising:
 exposing the substrate comprising an organic polymer to a first layer comprising a first plurality of dielectric dopant particles, wherein a thermal conductivity of the organic polymer is less than 5 Wm −1 K −1  and a lossiness that is less than a lossiness of the first plurality of dielectric dopant particles;   irradiating the substrate and the first layer to an energy source operating at an operating frequency such that the first plurality of dielectric dopant particles of the first layer diffuse into the organic polymer of the substrate; and   continuing the irradiating for a first desired time to achieve a first depth of penetration of the first plurality of dielectric dopant particles into the organic polymer.   
     
     
         2 . The method of  claim 1 , wherein a melting point temperature of the first plurality of dielectric dopant particles is greater than a melting point temperature of the organic polymer comprising the substrate. 
     
     
         3 . The method of  claim 1 , wherein the operating frequency ranges from about 2 GHz to about 3 GHz. 
     
     
         4 . The method of  claim 1 , wherein the substrate is a woven or non-woven comprising the organic polymer. 
     
     
         5 . The method of  claim 1 , wherein the organic polymer is polypropylene, polyethylene, nylon, aramids, polytetrafluoroethylene, or a combination thereof. 
     
     
         6 . The method of  claim 1 , wherein the first plurality of dielectric dopant particles have a diameter ranging from about 30 nm to about 5000 nm. 
     
     
         7 . The method of  claim 6 , wherein the first plurality of dopant particles comprise a composition including an oxide, a hydroxide, a nitride, a carbide of silicon, iron, titanium, magnesium, zirconium, nickel, cobalt, boron, or a combination thereof. 
     
     
         8 . The method of  claim 1 , wherein a melting temperature of the first plurality of dielectric dopant particles is greater than about 300° C. 
     
     
         9 . The method of  claim 1 , further comprising:
 exposing the substrate to a second layer comprising a second plurality of dielectric dopant particles, wherein the lossiness of the organic polymer that is less than a lossiness of the second plurality of dielectric dopant particles;   irradiating the substrate and the second layer to an energy source operating at the operating frequency such that the second plurality of dielectric dopant particles of the second layer diffuse into the organic polymer of the substrate; and   continuing the irradiating for a second desired time such that the second plurality of particles, having a composition that is different from a composition of particles of the first plurality, achieves a second depth of penetration of the second plurality of dielectric dopant particles into the organic polymer.   
     
     
         10 . The method of  claim 9 , wherein the penetration of the first plurality of dielectric dopant parties remains at the first desired depth of penetration. 
     
     
         11 . A method of doping a substrate with dielectric dopant particles, the method comprising:
 exposing the substrate comprising an organic polymer to a layer comprising the dielectric dopant particles, wherein a thermal conductivity of the organic polymer is less than 5 Wm −1 K −1  and a melting temperature of the layer of dielectric dopant particles is greater than about 300° C.;   irradiating the substrate and the layer to an energy source operating at an operating frequency such that the dielectric dopant particles of the layer diffuse into the organic polymer of the substrate; and   continuing the irradiating to achieve a depth of penetration of the dielectric dopant particles into the organic polymer.   
     
     
         12 . The method of  claim 11 , wherein the operating frequency ranges from about 2 GHz to about 3 GHz. 
     
     
         13 . The method of  claim 11 , wherein the substrate is a woven or non-woven comprising the organic polymer. 
     
     
         14 . The method of  claim 11 , wherein the organic polymer is polypropylene, polyethylene, nylon, aramids, polytetrafluoroethylene, or a combination thereof. 
     
     
         15 . The method of  claim 11 , wherein the first plurality of dielectric dopant particles have a diameter ranging from about 30 nm to about 5000 nm. 
     
     
         16 . The method of  claim 15 , wherein the first plurality of dopant particles comprise a composition including an oxide, a hydroxide, a nitride, a carbide of silicon, iron, titanium, magnesium, zirconium, nickel, cobalt, boron, or a combination thereof. 
     
     
         17 . A method of doping a substrate with dielectric dopant particles, the method comprising:
 exposing the substrate comprising an organic polymer to a first layer comprising a first plurality of dielectric dopant particles, wherein a thermal conductivity of the organic polymer is less than 5 Wm −1 K −1  and a lossiness that is less than a lossiness of the first plurality of dielectric dopant particles;   irradiating the substrate and the first layer to an energy source operating at a first operating frequency such that the first plurality of dielectric dopant particles of the first layer diffuse into the organic polymer of the substrate; and   continuing the irradiating for a first desired time to achieve a first depth of penetration of the first plurality of dielectric dopant particles into the organic polymer.   
     
     
         18 . The method of  claim 17 , further comprising:
 exposing the substrate to a second layer comprising a second plurality of dielectric dopant particles, wherein the lossiness of the organic polymer that is less than a lossiness of the second plurality of dielectric dopant particles;   irradiating the substrate and the second layer to an energy source operating at a second operating frequency such that the second plurality of dielectric dopant particles of the second layer diffuse into the organic polymer of the substrate; and   continuing the irradiating for a second desired time such that the second plurality of particles, having a composition that is different from a composition of particles of the first plurality, achieves a second depth of penetration of the second plurality of dielectric dopant particles into the organic polymer.   
     
     
         19 . The method of  claim 18 , wherein each of the first and second pluralities of dopant particles has a melting point temperature that is greater than a melting point temperature of the organic polymer comprising the substrate. 
     
     
         20 . The method of  claim 18 , wherein each of the first and second operating frequencies separately ranges from about 2 GHz to about 3 GHz.