Process for uniform and higher loading of metallic fillers into a polymer matrix using a highly porous host material

Abstract

In one aspect, embodiments are provided of metal coated fillers that include porous filler particles having pores and metal particles coated on the filler particles and inside the pores. In an exemplary embodiment, the weight of metal particles on the porous filler particles and inside the pores may range from 100 percent to 400 percent of the weight of the porous filler particles. The porous filler particles may have a porosity from 30 percent to 99 percent.

What is claimed is: 
     
         1 . A metal coated filler comprising:
 a plurality of porous filler particles having a plurality of pores; and   a plurality of metal particles coated on the porous filler particles and inside the plurality of pores;   the weight of metal particles on the porous filler particles and inside the pores ranges from 100 percent to 400 percent of the weight of the porous filler particles.   
     
     
         2 . The metal coated filler of  claim 1 , wherein the porous filler particles comprise siliceous filler particles, non-siliceous filler particles, or a combination thereof. 
     
     
         3 . The metal coated filler of  claim 1 , wherein the porous filler particles comprise:
 siliceous filler particles including perlite, vermiculite, pumice, montmorillonite, zeolites, or a combination thereof; and/or   non-siliceous filler particles including a ceramic, a porous metal, or a combination thereof.   
     
     
         4 . The metal coated filler of  claim 1 , wherein the porous filler particles comprise expanded perlite. 
     
     
         5 . The metal coated filler of  claim 4 , wherein:
 the expanded perlite has a size distribution ranging from about 5 microns to about 5 millimeters; and/or   the expanded perlite has a porosity ranging from about 40 percent to about 99 percent; and/or   the expanded perlite has a porosity ranging from about 80 percent to about 99 percent.   
     
     
         6 . The metal coated filler of  claim 1 , wherein the metal particles comprise gold, silver, platinum, copper, iron, aluminum, palladium, nickel, cobalt, zinc, and mixtures thereof. 
     
     
         7 . The metal coated filler of  claim 1 , further comprising a second metal coating on the metal coated filler. 
     
     
         8 . The metal coated filler of  claim 8 , wherein the second metal coating is a different metal than the metal particles. 
     
     
         9 . An article, a conductive paste, a material, or a thermally and/or electrically conductive injection moldable thermoplastic composite comprising the metal coated filler of  claim 1 . 
     
     
         10 . A metal coated filler comprising:
 a plurality of porous filler particles having a plurality of pores, the porous filler particles having a porosity from 30 percent to 99 percent; and   a plurality of metal particles coated on the porous filler particles and inside the plurality of pores;   the weight of metal particles on the porous filler particles and inside the pores ranges from 100 percent to 400 percent of the weight of the porous filler particles.   
     
     
         11 . The metal coated filler of  claim 10 , wherein the porous filler particles comprise siliceous filler particles, non-siliceous filler particles, or a combination thereof. 
     
     
         12 . The metal coated filler of  claim 10 , wherein the porous filler particles comprise:
 siliceous filler particles including perlite, vermiculite, pumice, montmorillonite, zeolites, or a combination thereof; and/or   non-siliceous filler particles including a ceramic, a porous metal, or a combination thereof.   
     
     
         13 . The metal coated filler of  claim 10 , wherein the porous filler particles comprise expanded perlite. 
     
     
         14 . The metal coated filler of  claim 10 , wherein:
 the expanded perlite has a size distribution ranging from about 5 microns to about 5 millimeters; and/or   the expanded perlite has a porosity ranging from about 40 percent to about 99 percent; and/or   the expanded perlite has a porosity ranging from about 80 percent to about 99 percent.   
     
     
         15 . The metal coated filler of  claim 11 , wherein the metal particles comprise gold, silver, platinum, copper, iron, aluminum, palladium, nickel, cobalt, zinc, and mixtures thereof. 
     
     
         16 . The metal coated filler of  claim 11 , further comprising a second metal coating on the metal coated filler, wherein the second metal coating is a different metal than the metal particles. 
     
     
         17 . An article, a conductive paste, a material, or a thermally and/or electrically conductive injection moldable thermoplastic composite comprising the metal coated filler of  claim 11 . 
     
     
         18 . An electrically and/or thermally conductive material comprising:
 a matrix material; and   a metal coated filler comprising a plurality of porous filler particles having a plurality of pores, and a plurality of metal particles coated on the porous filler particles and inside the plurality of pores, wherein the weight of metal particles on the porous filler particles and inside the pores ranges from 100 percent to 400 percent of the weight of the porous filler particles;   wherein the electrically and/or thermally conductive material has an electrical conductivity greater than 10 Siemens per centimeter and/or a thermal conductivity greater than 20 Watts per meter Kelvin.   
     
     
         19 . The electrically and/or thermally conductive material of  claim 18 , wherein the electrically and/or thermally conductive material has an electrical conductivity greater than 10 Siemens per centimeter. 
     
     
         20 . The electrically and/or thermally conductive material of  claim 18 , wherein the electrically and/or thermally conductive material has a thermal conductivity greater than 20 Watts per meter Kelvin.