Low molecular weight hydrogenated nitrile rubber

Abstract

The present invention relates to hydrogenated nitrile rubber polymers having lower molecular weights and narrower molecular weight distributions than those known in the art. The present invention is also related to shaped articles containing hydrogenated nitrile rubber polymers having lower molecular weights and narrower molecular weight distributions than those known in the art.

1 . A hydrogenated nitrile rubber having a molecular weight (MW) in the range of from 30,000 to 250,000, a Mooney viscosity (ML 1+4 @ 100 deg. C) in the range of from 3 to 50, and a MWD (or polydispersity index) of less than 2.5.  
     
     
         2 . A hydrogenated nitrile rubber according to  claim 1  wherein the molecular weight (Mw) is in the range of from 40,000 to 220,000.  
     
     
         3 . A hydrogenated nitrile rubber according to  claim 1  wherein the polydispersity index is less than 2.3.  
     
     
         4 . A hydrogenated nitrile rubber according to  claim 1  wherein the rubber has a Mooney viscosity (ML 1+4 @ 100 deg. C) of less than 35.  
     
     
         5 . (Cancelled).  
     
     
         6 . A shaped article comprising a hydrogenated nitrile rubber having a molecular weight (MW) in the range of from 30,000 to 250,000, a Mooney viscosity (ML 1+4 @100 deg. C) in the range of from 3 to 50, and a MWD (or polydispersity index) of less than 2.5.  
     
     
         7 . A shaped article according to  claim 6 , wherein the shaped article is a seal, a hose, a bearing pad, a stator, a well head seal, a valve plate, a cable sheathing, a wheel, a roller or a pipe seal.