Surface bonding in halogenated polymeric components

Abstract

Etching the surface (activating the surface) of a halogenated polymer component with an electron beam generates a set of free radical sites in polymeric chains of the surface that sustain for at least 4 hours in an inert environment. The inert environment is provided by a noble gas, nitrogen, a static free space, and/or a vacuum. Items such as dynamic seals, static seals, gaskets, pump diaphragms, hoses, and o-rings all benefit from precursors made according to the technique.

1 . A method for etching an article made of halogenated polymer, comprising: 
 (a) etching a surface of said article with an electron beam; and    (b) placing said surface in an inert environment at a predetermined temperature;    wherein said electron beam energizes said surface with sufficient energy for dislodging a plurality of halogen atoms from said halogenated polymer of said surface and for generating thereby a set of initial residual free radical sites in polymeric chains of said surface upon conclusion of said etching, and said inert environment and said predetermined temperature are sufficient for sustaining at least 99 percent of said free radical sites of said set of initial residual free radical sites for at least 4 hours.    
     
     
         2 . A method according to  claim 1  wherein said inert environment and said predetermined temperature are sufficient for sustaining at least 90 percent of said free radical sites of said set of initial residual free radical sites for at least 8 hours.  
     
     
         3 . A method according to  claim 1  wherein said inert environment comprises a noble gas.  
     
     
         4 . A method according to  claim 1  wherein said inert environment comprises a noble gas at a pressure of less than 0.1 atmospheres.  
     
     
         5 . A method according to  claim 1  wherein said inert environment comprises any of nitrogen, an applied vacuum, and a space free of electrical static.  
     
     
         6 . A method according to  claim 1  wherein said inert environment comprises nitrogen at a pressure of less than 0.1 atmospheres.  
     
     
         7 . A method according to  claim 1  wherein said generating generates electron beam radiation of from about 0.1 MeRAD to about 40 MeRAD.  
     
     
         8 . A method according to  claim 1  wherein said generating generates electron beam radiation from about 5 MeRAD to about 20 MeRAD.  
     
     
         9 . An etched halogenated polymer article made by a process, comprising: 
 (a) etching a surface of said article with an electron beam; and    (b) placing said surface in an inert environment at a predetermined temperature;    wherein said electron beam energizes said surface with sufficient energy for dislodging a plurality of halogen atoms from said halogenated polymer of said surface and for generating thereby a set of initial residual free radical sites in polymeric chains of said surface upon conclusion of said etching, and said inert environment and said predetermined temperature are sufficient for sustaining at least 99 percent of said free radical sites of said set of initial residual free radical sites for at least 4 hours.    
     
     
         10 . An article according to  claim 9  wherein said inert environment and said predetermined temperature are sufficient for sustaining at least 90 percent of said free radical sites of said set of initial residual free radical sites for at least 8 hours.  
     
     
         11 . An article according to  claim 9  wherein said inert environment comprises a noble gas.  
     
     
         12 . An article according to  claim 9  wherein said inert environment comprises a noble gas at a pressure of less than 0.1 atmospheres.  
     
     
         13 . An article according to  claim 9  wherein said inert environment comprises any of nitrogen, an applied vacuum, and a space free of electrical static.  
     
     
         14 . An article according to  claim 9  wherein said inert environment comprises nitrogen at a pressure of less than 0.1 atmospheres.  
     
     
         15 . An article according to  claim 9  wherein said generating generates electron beam radiation of from about 0.1 MeRAD to about 40 MeRAD.  
     
     
         16 . An article according to  claim 9  wherein said generating generates electron beam radiation from about 5 MeRAD to about 20 MeRAD.  
     
     
         17 . An article according to  claim 9  wherein said article is a precursor component for a sealant article, said sealant article selected from the group consisting of a seal, a gasket, a pump diaphragm, a hose, and an o-ring.