Multilayered polymeric structure

Abstract

A multilayered polymeric structure having at least two polymeric layers is provided, each layer being a mixture of a polymeric composition with carbon fibrils. The multilayer polymeric structure may include an electrically conductive material between the first and second polymeric layers. A process for making a multilayered polymeric structure for packaging electronic components is also provided. The multilayered polymeric material is used to form trays and packages for containing electrical components.

1 . A multilayered polymeric structure for protecting electronic components comprising at least a first polymeric layer and a second polymeric layer in surface contact with one another, said first and second polymeric layers each containing a different amount of carbon fibrils.  
   
   
       2 . The multilayered polymeric structure according to  claim 1 , wherein said first and said second polymeric layers each comprise from about 0.25% to about 35% by weight of carbon fibrils.  
   
   
       3 . The multilayered polymeric structure according to  claim 1 , wherein said first and said second polymeric layers each comprise from about 1.0% to about 15% by weight of carbon fibrils.  
   
   
       4 . The multilayered polymeric structure according to  claim 1 , wherein said first and said second polymeric layers each comprise from about 2.0% to about 7% by weight of carbon fibrils.  
   
   
       5 . The multilayered polymeric structure according to  claim 1 , wherein said first polymeric layer comprises from about 0.25% to about 25% by weight of carbon fibrils and said second polymeric layer comprises from about 2% to about 35% by weight of carbon fibrils.  
   
   
       6 . The multilayered polymeric structure according to  claim 1 , further comprising at least an electrically conductive material between said first polymeric layer and said second polymeric layer.  
   
   
       7 . The multilayered polymeric structure according to  claim 6 , wherein the electrically conductive material is an adhesive.  
   
   
       8 . The multilayered polymeric structure according to  claim 1 , wherein the surface resistance in said second polymeric layer is at least one order of magnitude greater than the surface resistance of said first polymeric layer.  
   
   
       9 . The multilayered polymeric structure according to  claim 1 , wherein the surface resistance of each of said polymeric layers is in the range of 1×10 1  ohms per square to 1×10 12  ohms per square.  
   
   
       10 . The multilayered polymeric structure according to  claim 9 , wherein the surface resistance of said second polymeric layer is in the range of 1×10 to 1×10 6  ohms per square.  
   
   
       11 . The multilayered polymeric structure according to  claim 9 , wherein the surface  10  resistance of said first polymeric layer is in the range of 1×10 6  ohms per square to 1×10 12  ohms per square.  
   
   
       12 . A process for making a multilayered polymeric structure for protecting an electronic component which comprises: 
 (a) forming at least a first polymeric layer and a second polymeric layer, each layer comprising a different amount of carbon fibrils;    (b) combining said first and second polymeric layer to form said multilayered polymeric structure.    
   
   
       13 . The process according to  claim 12 , wherein said first and second polymeric layers comprise from about 0.25% to about 35% by weight of carbon fibrils.  
   
   
       14 . The process according to  claim 12 , wherein said first polymeric layer comprises from 0.25 to 25% by weight carbon fibrils and said second polymeric layer comprises from 2% to 35% by weight carbon fibrils.  
   
   
       15 . The process according to  claim 12 , wherein said layers are combined by coextrusion or lamination, or by two shot or multi-shot injection molding or by insert injection molding.  
   
   
       16 . The process according to  claim 12 , wherein said first polymeric layer has a higher surface resistance than said second polymeric layer.  
   
   
       17 . The process according to  claim 16 , wherein said multilayered polymeric structure is formed into a tray or packaging material, wherein said electronic component is in contact with said first polymeric layer.  
   
   
       18 . The process according to  claim 16 , further comprising forming third polymeric layer in surface contact with said first or said second polymeric layer, said third polymeric layer comprising from about 0.25% to about 35% by weight carbon fibrils.  
   
   
       19 - 22 . (canceled)  
   
   
       23 . A container for sensitive electrical components comprising: 
 (a) a first layer of polymeric material adapted to support an electrical component, said first polymeric layer comprising from about 0.25% to about 25% by weight carbon fibrils and having a resistivity in the range of from about 1×10 5  ohms per square to about 1×10 12  ohms per square; and    (b) a second layer of polymeric material in surface contact with said first layer, said second layer forming the outer layer of said container comprising from about 2% to about 35% by weight carbon fibrils and having a resistivity in the range of from about 1×10 1  ohms per square to about 1×10 6  ohms per square.    
   
   
       24 . The container of  claim 23 , further comprising at least an electrically conductive material between said first polymeric layer and said second polymeric layer.  
   
   
       25 . The container of  claim 24 , wherein the electrically conductive material is an adhesive.  
   
   
       26 . The container of  claim 23 , wherein said first polymeric layer and said second polymeric layer comprise a hybrid mixture of PETG and PBT said mixture comprising from about 0% to about 100% by weight PETG, the remaining portion being PBT.  
   
   
       27 . The container of  claim 23 , further comprising a third polymeric layer in surface contact with said first or said second layer of polymeric material, said third polymeric layer comprising from about 0.25% to about 35% by weight carbon fibrils and having a resistivity in the range from about 1×10 1  ohms per square to about 1×10 1  ohms per square.  
   
   
       28 . A protective covering for an electrical current carrying cable comprising: 
 (a) a first layer of polymeric material adapted to support an electrical component, said first polymeric layer comprising from about 0.25% to about 25% by weight carbon fibrils and having a resistivity in the range of from about 1×10 5  ohms per square to about 1×10 12  ohms per square; and    (b) a second layer of polymeric material in surface contact with said first layer, said second layer forming the outer layer of said container comprising from about 2% to about 35% by weight carbon fibrils and having a resistivity in the range of from about 1×10 1  ohms per square to about 1×10 6  ohms per square.