Halogenated polyisoolefins with reduced halogenated oligomers

Abstract

A halogenated polyisoolefin copolymer is composed of at least one isoolefin monomer, at least one multiolefin monomer, a halogen content of 0.05-2.5 mol %, and a halogenated oligomer content of less than 65% of total oligomer content in the halogenated polyisoolefin copolymer. The copolymer has low halogen content and significantly reduced levels of halogenated oligomers. The copolymer is especially useful in the pharmaceutical and food industries, for example as pharmaceutical and food product seals and closures.

1 . A halogenated polyisoolefin copolymer comprising:
 at least one isoolefin monomer;   at least one multiolefin monomer;   a halogen content of 0.05-2.5 mol %; and   a halogenated oligomer content of less than 65% of total oligomer content in the halogenated polyisoolefin copolymer.   
     
     
         2 . The copolymer according to  claim 1 , wherein the at least one multiolefin monomer is present in an amount of 2.4 mol % to 10 mol %. 
     
     
         3 . The copolymer according to  claim 1 , wherein the halogen content is 0.05-1 mol %. 
     
     
         4 . The copolymer according to  claim 1 , comprising a content of non-halogenated double bonds of 2.5-4.5 mol %. 
     
     
         5 . The copolymer according to  claim 1 , wherein the halogenated oligomer content is 50% or less of total oligomer content in the copolymer. 
     
     
         6 . The copolymer according to  claim 1 , wherein the at least one isoolefin monomer comprises isobutene. 
     
     
         7 . The copolymer according to  claim 1 , wherein the at least one multiolefin monomer comprises isoprene. 
     
     
         8 . The copolymer according to  claim 1 , further comprising a stabilizer, the stabilizer comprising a mixture of a LOCST compound and a metal carboxylate, the metal carboxylate present in an amount of 1.25 wt % or less based on weight of the copolymer. 
     
     
         9 . The copolymer according to  claim 8 , wherein the metal carboxylate comprises calcium stearate. 
     
     
         10 . An article of manufacture, in particular a pharmaceutical or food product seal or closure, comprising the copolymer as defined in  claim 1 . 
     
     
         11 . The article according to  claim 10 , which is a closure for a parenteral (I.V.) vial, a closure for an injection vial, a closure for a vial containing freeze dried pharmaceutical product, a closure for a blood collection tube, a closure for a diagnostic tube, a closure for an infusion container, a closure for an insulin container, a closure for a dental anesthetic container, a plunger or plunger tip for a syringe, a disc, a gasket, an intravenous drug delivery component, a seal for a pre-filled syringe, a seal for an infusion pump or a seal for an inhaler. 
     
     
         12 . (canceled) 
     
     
         13 . (canceled) 
     
     
         14 . (canceled) 
     
     
         15 . (canceled) 
     
     
         16 . (canceled) 
     
     
         17 . (canceled) 
     
     
         18 . (canceled) 
     
     
         19 . The copolymer according to  claim 1 , wherein:
 the at least one multiolefin monomer is present in an amount of 2.5 mol % to 7.5 mol %;   the halogen content is 0.05-1 mol % or is 0.15-0.49 mol %;   the content of non-halogenated double bonds is 2.5-4.5 mol %;   the halogenated oligomer content is 35% or less of total oligomer content in the copolymer; and   the copolymer further comprises a stabilizer mixture of LOST compound and metal carboxylate, wherein the metal carboxylate is present in an amount of 1.25 wt % or less based on weight of the copolymer.   
     
     
         20 . The copolymer according to  claim 19 , wherein:
 the at least one isoolefin monomer comprises isobutene;   the at least one multiolefin monomer comprises isoprene;   the isoprene is present in an amount of 3.1 mol % to 3.65 mol %;   the halogen is bromine, and the halogenated oligomer is brominated oligomer;   the bromine content is 0.15-0.49 mol %;   the content of non-halogenated double bonds is 2.6-4.09 mol %;   the brominated oligomer content is 15% or less of total oligomer content in the copolymer; and   the metal carboxylate of the stabilizer mixture is calcium stearate, wherein the calcium stearate is present in an amount of 0.5-1.24 wt % based on weight of the copolymer.   
     
     
         21 . The article of  claim 11 , wherein the at least one multiolefin monomer is present in the copolymer in an amount of 2.4 mol % to 10 mol %, and the halogen content of the copolymer is 0.05-1 mol %. 
     
     
         22 . The article of  claim 11 , wherein the halogenated polyisoolefin copolymer has a content of non-halogenated double bonds of 2.5-4.5 mol %. 
     
     
         23 . The article of  claim 11 , wherein the halogenated oligomer content is 50% or less of total oligomer content in the copolymer. 
     
     
         24 . The article of  claim 11 , wherein the at least one isoolefin monomer comprises isobutene, and the at least one multiolefin monomer comprises isoprene. 
     
     
         25 . The article of  claim 11 , wherein the halogenated polyisoolefin copolymer further comprises a stabilizer, the stabilizer comprising a mixture of a LOCST compound and a metal carboxylate, the metal carboxylate present in an amount of 1.25 wt % or less based on weight of the copolymer or in an amount of 0.2-1.24 wt %. 
     
     
         26 . The article of  claim 11 , wherein
 the at least one multiolefin monomer is present in an amount of 2.5 mol % to 7.5 mol %;   the halogen content of the copolymer is 0.05-1 mol % or is 0.15-0.49 mol %;   the content of non-halogenated double bonds is 2.5-4.5 mol % of the copolymer;   the halogenated oligomer content is 35% or less of total oligomer content in the copolymer; and   the copolymer further comprises a stabilizer mixture of LOST compound and metal carboxylate, wherein the metal carboxylate is present in an amount of 1.25 wt % or less based on weight of the copolymer.   
     
     
         27 . The article of  claim 26 , wherein:
 the at least one isoolefin monomer comprises isobutene;   the at least one multiolefin monomer comprises isoprene;   the isoprene is present in an amount of 3.1 mol % to 3.65 mol %;   the halogen is bromine, and the halogenated oligomer is brominated oligomer;   the bromine content is 0.15-0.49 mol %;   the content of non-halogenated double bonds is 2.6-4.09 mol %;   the brominated oligomer content is 15% or less of total oligomer content in the copolymer; and   the metal carboxylate of the stabilizer mixture is calcium stearate, wherein the calcium stearate is present in an amount of 0.5-1.24 wt % based on weight of the copolymer.