Heat pipe and manufacturing method thereof

Abstract

A heat pipe and manufacturing method thereof. A pipe is provided and shaped. A molding bar is inserted into the pipe. A wick structure is formed in the pipe. The molding bar is separated from the pipe. A working fluid is added and confined in a closed space of the pipe. The pipe is shaped before formation of the wick structure therein to prevent damage to the wick structure.

1 . A tie-layer adhesive composition comprising: 
 (a) 80 to 95 weight percent or more, based on the weight of the composition, ethylene-C 4-8  α-olefin copolymer base resin having hard and soft phases that form a network structure, density of 0.925 g/cm 3  or less, melt index from 0.3 to 5 g/10 min and which when in the pelletized form, exhibits a reduction in ER of 10 percent or more to a final ER value of 1.0 or less upon rheometric low shear modification or solution dissolution, and    (b) less than 5 weight percent, based on the weight of the composition, modified polyolefin which is an ethylene-C 3-8  α-olefin copolymer having a density of 0.905 to 0.965 g/cm 3  grafted with 0.5 to 2.5 weight percent ethylenically unsaturated carboxylic acid or ethylenically unsaturated carboxylic acid derivative.    
   
   
       2 . The adhesive composition of  claim 1  having a melt index from 0.5 to 5 g/10 min and wherein the modified polyolefin (b) is an ethylene-α-olefin copolymer grafted with maleic anhydride.  
   
   
       3 . (canceled)  
   
   
       4 . The adhesive composition of  claim 2  wherein (a) is a copolymer of ethylene and hexene-1 having a melt index of 0.5 to 2.5 g/10 min.  
   
   
       5 . The adhesive composition of  claim 4  wherein (a) has a density of 0.910 to 0.920 g/cm 3  and melt index of 0.5 to 1.5 g/10 min.  
   
   
       6 . The adhesive composition of  claim 2  wherein (b) is a grafted high density polyethylene copolymer having a melt index from 0.5 to 20 g/10 min and density from 0.945 to 0.965 g/cm 3 .  
   
   
       7 . The adhesive composition of  claim 6  wherein (b) is grafted with 0.75 to 2.2 weight percent maleic anhydride and has a melt index from 4.5 to 8 g/10 min.  
   
   
       8 . The adhesive composition of  claim 2  wherein (b) is a grafted linear low density polyethylene copolymer having a melt index from 0.5 to 20 g/10 min and density from 0.910 to 0.930 g/cm 3 .  
   
   
       9 . The adhesive composition of  claim 8  wherein (b) is grafted with 0.75 to 2.2 weight percent maleic anhydride and has a melt index from 4.5 to 8 g/10 min.  
   
   
       10 . The adhesive composition of  claim 2  which contains 95.5 to 99.5 weight percent (a) and 0.5 to 4.5 weight percent (b).  
   
   
       11 . A multi-layer barrier film comprising a barrier resin layer wherein the barrier resin is selected from the group consisting of ethylene-vinyl alcohol copolymer and nylon and adhesively bonded thereto a tie-layer adhesive composition comprising 80 to 95 weight percent or more, based on the weight of the composition, ethylene-C 4-8  α-olefin copolymer base resin having hard and soft phases that form a network structure, density of 0.925 g/cm 3  or less, melt index from 0.3 to 5 g/10 min., and which when in the pelletized form, exhibits a reduction in ER of 10 percent or more to a final ER value of 1.0 or less upon rheometric low shear modification or solution dissolution, and less than 5 weight percent, based on the weight of the composition, modified polyolefin which is an ethylene-C 3-8  α-olefin copolymer having a density of 0.905 to 0.965 g/cm 3  grafted with 0.5 to 2.5 weight percent ethylenically unsaturated carboxylic acid or ethylenically unsaturated carboxylic acid derivative.  
   
   
       12 . The barrier film of  claim 11  produced by extrusion or coextrusion processes.  
   
   
       13 . The barrier film of  claim 11  wherein the tie-layer adhesive composition has a melt index from 0.5 to 5 g/10 min and the modified polyolefin is an ethylene-α-olefin copolymer grafted with maleic anhydride.  
   
   
       14 . The barrier film of  claim 13  wherein the base resin is a copolymer of ethylene and hexene-1 and has a melt index of 0.5 to 2.5 g/10 min and the modified polyolefin is a grafted high density polyethylene copolymer having a melt index from 0.5 to 20 g/10 min and density from 0.945 to 0.965 g/cm 3 .  
   
   
       15 . The barrier film of  claim 13  wherein the base resin is a copolymer of ethylene and hexene-1 and has a melt index of 0.5 to 2.5 g/10 min and the modified polyolefin is a grafted linear low density polyethylene copolymer having a melt index from 0.5 to 20 g/10 min and density from 0.910 to 0.930 g/cm 3 .  
   
   
       16 . The barrier film of  claim 11  wherein the tie-layer adhesive composition is adhesively bonded to both sides of the barrier resin layer.  
   
   
       17 . The barrier film of  claim 11  comprising a further polyolefin resin layer wherein the polyolefin resin is selected from the group consisting of low density polyethylene, linear low density polyethylene, high density polyethylene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylate ester copolymer, ethylene-methacrylic acid copolymer, ethylene-methacrylic ester copolymer and ionomer and wherein the tie-layer adhesive is disposed between the barrier resin layer and said polyoloefin resin layer.