Fluoroelastomer compositions

Abstract

Fluoropolymers comprising a fluoroelastomer matrix incorporating therein particles of a semicrystalline fluoropolymer formed of tetrafluoroethylene (TFE) homopolymers or copolymers, wherein the average particle sizes of the semicrystalline fluoropolymer latex range from 10 to 100 nm.

1 . Cured fluoropolymer compositions comprising a fluoroelastomer and a semicrystalline fluoropolymer latex formed by tetrafluoroethylene (TFE) homopolymers, or TFE copolymers with one or more monomers containing at least one unsaturation of ethylene type in amounts ranging from 0.01% to 10% by moles, obtainable by mixing the semicrystalline fluoropolymer latex with the fluoroelastomer, subsequent coagulation and drying.  
   
   
       2 . Cured fluoropolymer compositions according to  claim 1  obtainable by polymerizing in a first step the semicrystalline fluoropolymer and in a second step the fluoroelastomer.  
   
   
       3 . Cured fluoropolymer compositions according to  claim 1  wherein the semicrystalline fluoropolymer amount inside the fluoroelastomer matrix is in the range 2-40% by weight of the total of the polymeric mixture.  
   
   
       4 . Cured fluoropolymer compositions according to  claim 3  wherein the semicrystalline fluoropolymer amount inside the fluoroelastomer matrix is in the range 5-30% by weight of the total of the polymeric mixture.  
   
   
       5 . Cured fluoropolymer compositions according to  claim 1  wherein the semicrystalline polymer is based on PTFE modified with comonomers with ethylene unsaturation both of hydrogenated and fluorinated type.  
   
   
       6 . Cured fluoropolymer compositions according to  claim 5  wherein the hydrogenated comonomers are selected from the group consisting of ethylene, propylene, methylmethacrylate, methacrylic acid, butylacrylate, hydroxyethylhexylacrylate, and styrene.  
   
   
       7 . Cured fluoropolymer compositions according to  claim 5  wherein the fluorinated comonomers are selected from the group consisting of: 
 perfluoroolefins C 3 -C 8 ;    hydrogenated fluoroolefins C 2 -C 8 ;    chloro- and/or bromo- and/or iodo-fluoroolefins C 2 -C 8 ;    (per)fluoroalkylvinylethers (PAVE CF 2 ═CFOR f , wherein R f  is a (per)fluoroalkyl C 1 -C 6 ;    (per)fluoro-oxyalkyvinylethers CF 2 ═CFOX, wherein X is a alkyl C 1 -C 12 , or an oxyalkyl C 1 -C 12 , or a (per)fluoro-oxyalkyl C 1 -C 12  having one or more ether groups; fluorodioxoles.    
   
   
       8 . Cured fluoropolymer compositions according to  claim 5  wherein the fluorinated comonomers are selected from the group consisting of perfluoromethyl-, ethyl-, propylvinylether and perfluorodioxoles.  
   
   
       9 . Cured fluoropolymer compositions according to  claim 1  wherein the fluoroelastomer is selected from the following classes: 
 (1) vinylidene fluoride (VDF)-based copolymers, wherein VDF is copolymerized with at least one comonomer selected from the group consisting of: perfluoroolefins C 2 -C 8 , chloro- and/or bromo- and/or iodofluoroolefins C 2 -C 8 , (per)fluoroalkyl-vinylethers (PAVE) CF 2 ═CFOR f , wherein R f  is a (per)fluoroalkyl C 1 -C 6 , perfluoro-oxyalkylvinylethers CF 2 ═CFOX, wherein X is a perfluoro-oxyalkyl C 1 -C 12  having one or more ether groups, non fluorinated olefins (Ol) C 2 -C 8 ;    (2) tetrafluoroethylene (TFE)-based copolymers, wherein TFE is copolymerized with at least one comonomer selected from the group consisting of (per)fluoroalkyvinylethers (PAVE) CF 2 ═CFOR f , wherein R f  is as above defined; perfluoro-oxyalkyvinylethers CF 2 ═CFOX, wherein X is as above defined; fluoroolefins C 2 -C 8  containing hydrogen and/or chlorine and/or bromine and/or iodine atoms; non fluorinated olefins (Ol) C 2 -C 8 .    
   
   
       10 . Cured fluoropolymer compositions according to  claim 9  wherein the fluorelastomer is selected from the following compositions expressed by moles: 
 (a) vinylidene fluoride (VDF) 45-85%, hexafluoropropene (HFP) 15-45% tetrafluoroethylene (TFE) 0-30%;    (b) vinylidene fluoride (VDF) 50-80%, perfluoroalkylvinylether (PAVE) 5-50%, tetrafluoroethylene (TFE) 0-20%;    (c) vinylidene fluoride (VDF) 20-30%, non fluorinated olefins (Ol) C 2 -C 8  10-30%, hexafluoropropene (HFP) and/or perfluoroalkylvinylether (PAVE) 18-27%, tetrafluoroethylene (TFE) 10-30%;    (d) tetrafluoroethylene (TFE) 50-80%, perfluoroalkylvinylether (PAVE) 20-50%;    (e) tetrafluoroethylene (TFE) 45-65%, non fluorinated olefins (Ol) C 2 -C 8  20-55%, vinylidene fluoride 0-30%    (f) tetrafluoroethylene (TFE) 32-60%, non fluorinated olefins (Ol) C 2 -C 8  10-40%, perfluoroalkylvinylether (PAVE) 20-40%;    (g) tetrafluoroethylene (TFE) 33-75%, perfluoroalkylvinylether (PAVE) 15-45%, vinylidene fluoride (VDF) 5-30%.    
   
   
       11 . Cured fluoropolymer compositions according to  claim 1  wherein the fluoroelastomer comprises also monomer units deriving from a bis-olefin having the formula:  
     
       
         
         
             
             
         
       
     
     wherein 
 R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , equal to or different from each other, are H or alkyl C 1 -C 5 ;  
 Z is a linear or branched, alkylene or cycloalkylene C 1 -C 18  radical, optionally containing oxygen toms optionally at least partially fluorinated, or a (per)fluoropolyoxyalkylene radical.  
 
   
   
       12 . Cured fluoropolymer compositions according to  claim 11  wherein the unit amount in the chain deriving from the bis-olefin is in the range 0.01-1.0% by moles of the other monomer units forming the fluoroelastomer base structure.  
   
   
       13 . Cured fluoropolymer compositions according to  claim 1  wherein the fluoroelastomers are cured by peroxidic route.  
   
   
       14 . Cured fluoropolymer compositions according to  claim 1  wherein when the fluoroelastomers contain cyano groups they are cured by tin organic compounds and/or diaromatic aminic compounds.  
   
   
       15 . Cured fluoropolymer compositions according to  claim 1  wherein the fluoroelastomers are cured by tin organic compounds and/or diaromatic aminic compounds and optionally by peroxidic route if in the polymeric chain iodine and/or bromine atoms are present.  
   
   
       16 . Cured fluoropolymer compositions according to  claim 1  wherein the one or more monomers containing at least one unsaturation of ethylene type are present in amounts ranging from 0.5% to 5% by moles.  
   
   
       17 . Cured fluoropolymer compositions according to  claim 7  wherein the perfluoroolefins C 3 -C 8  are selected from the group consisting of hexafluoropropene (HFP) and hexafluoroisobutene.  
   
   
       18 . Cured fluoropolymer compositions according to  claim 7  wherein the hydrogenated fluoroolefins C 2 -C 8  are selected from the group consisting of vinyl fluoride (VF), vinylidene fluoride (VDF), trifluoroethylene and perfluoroalkylethylene CH 2 ═CH—R f , wherein R f  is a perfluoroalkyl C 1 -C 6 .  
   
   
       19 . Cured fluoropolymer compositions according to  claim 7  wherein the chlorofluoroolefin C 2 -C 8  is chlorotrifluoroethylene (CTFE).  
   
   
       20 . Cured fluoropolymer compositions according to  claim 7  wherein the (per)fluoroalkylvinyl-ethers (PAVE) (CF 3 ═CF)R f ) are selected from the group consisting of CF 3 , C 2 F 5  and C 3 F 7 .  
   
   
       21 . Cured fluoropolymer compositions according to  claim 7  wherein the (per)fluorooxyalkyl C 1 -C 12  having one or more ether groups is perfluoro-2-propoxy-propyl.  
   
   
       22 . Cured fluoropolymer compositions according to  claim 9  wherein the perfluoroolefin C 2 -C 8  is selected from the group consisting of tetrafluoroethylene (TFE) and hexafluoropropene (HFP).  
   
   
       23 . Cured fluoropolymer compositions according to  claim 9  wherein the chloro- and/or bromo-fluoro-olefins C 2 -C 8  are selected from the group consisting of chlorotrifluoroethylene (CTFE) and bromotrifluoroethylene.  
   
   
       24 . Cured fluoropolymer compositions according to  claim 9  wherein the (per)fluoroalkyl-vinylethers (PAVE) CF 2 —CFOR f  are selected from the group consisting of trifluoromethyl, bromodifluoromethyl and pentafluoropropyl.  
   
   
       25 . Cured fluoropolymer compositions according to  claim 9  wherein the perfluorooxyalkylvinylether CF 2 ═CFOX is perfluoro-2-propoxy-propyl.  
   
   
       26 . Cured fluoropolymer compositions according to  claim 9  wherein the nonfluorinated olefins (Ol) C 2 -C 8  are selected from the group consisting of ethylene and propylene.  
   
   
       27 . A sealing manufactured article comprising the cured fluoropolymer compositions according to  claim 1 .  
   
   
       28 . The sealing manufactured article according to  claim 27 , wherein the sealing manufactured article is an O-ring.  
   
   
       29 . Cured fluoropolymers comprising a fluoroelastomer matrix incorporating therein particles of a semicrystalline fluoropolymer latex formed by tetrafluoroethylene (TFE) homopolymers, or TFE copolymers with one or more monomers containing at least one unsaturation of ethylene type in amounts ranging from 0.01% to 10% by moles.  
   
   
       30 . Cured fluoropolymers according to  claim 29  obtainable by mixing the semicrystalline fluoropolymer latex with the fluoroelastomer latex and subsequent coagulation.  
   
   
       31 . Cured fluoropolymers according to  claim 29  obtainable by polymerizing in a first step the semicrystalline fluoropolymer and in a second step the fluoroelastomer.  
   
   
       32 . Cured fluoropolymers according to  claim 29  wherein the semicrystalline fluoropolymer amount inside the fluoroelastomer matrix is in the range 2-40% by weight of the total of the polymeric mixture.  
   
   
       33 . Cured fluoropolymers according to  claim 32  wherein the semicrystalline fluoropolymer amount inside the fluoroelastomer matrix is in the range 5-30% by weight of the total of the polymeric mixture.  
   
   
       34 . Cured fluoropolymers according to  claim 29  wherein the semicrystalline polymer is based on PTFE modified with comonomers with ethylene unsaturation both of hydrogenated and fluorinated type.  
   
   
       35 . Cured fluoropolymers according to  claim 34  wherein the hydrogenated comonomers are selected from the group consisting of ethylene, propylene, methylmethacrylate, methacrylic acid, butylacrylate, hydroxyethylhexylacrylate, and styrene.  
   
   
       36 . Cured fluoropolymers according to  claim 34  wherein the fluorinated comonomers are selected from the group consisting of 
 perfluoroolefins C 3 -C 8 ;    hydrogenated fluoroolefins C 2 -C 8 ;    chloro- and/or bromo- and/or iodo-fluoroolefins C 2 -C 8 ;    (per)fluoroalkylvinyl ethers (PAVE) CF 2 ═CFOR f , wherein R f  is a (per)fluoroalkyl C 1 -C 6 ;    (per)fluoro-oxyalkyvinylethers CF 2 ═CFOX, wherein X is an alkyl C 1 -C 12 , or an oxyalkyl C 1 -C 12 , or a (per)fluoro-oxyalkyl C 1 -C 12  having one or more ether groups; fluorodioxoles.    
   
   
       37 . Cured fluoropolymers according to  claim 34  wherein the fluorinated comonomers are selected from the group consisting of perfluoromethyl-, ethyl-, propyl-vinylether and perfluorodioxoles.  
   
   
       38 . Cured fluoropolymers according to  claim 29  wherein the fluoroelastomer is selected from the following classes: 
 (1) vinylidene fluoride (VDF)-based copolymers, wherein VDF is copolymerized with at least one comonomer selected from the group consisting of: perfluoroolefins C 2 -C 8 , chloro- and/or bromo- and/or iodofluoroolefins C 2 -C 8 , (per)fluoroalkyl-vinylethers (PAVE) CF 2 ═CFOR f , wherein R f  is a (per)fluoroalkyl C 1 -C 6 , perfluoro-oxyalkyvinylethers CF 2 ═CFOX, wherein X is a perfluoro-oxyalkyl C 1 -C 12  having one or more ether groups, non fluorinated olefins (Ol) C 2 -C 8 ;    (2) Tetrafluoroethylene (TFE)-based copolymers, wherein TFE is copolymerized with at least one comonomer selected from the group consisting of (per)fluoroalkylvinylethers (PAVE) CF 2 ═CFOR f , wherein R f  is as above defined;    perfluoro-oxyalkyvinylethers CF 2 ═CFOX, wherein X is as above defined; fluoroolefins C 2 -C 8  containing hydrogen and/or chlorine and/or bromine and/or iodine atoms; non fluorinated olefins (Ol) C 2 -C 8 ; perfluorovinylethers containing hydrocyanic groups.    
   
   
       39 . Cured fluoropolymers according to  claim 38  wherein the fluoroelastomers is selected from the following compositions expressed by moles: 
 (a) vinylidene fluoride (VDF) 45-85%, hexafluoropropene (HFP) 15-45% tetrafluoroethylene (TFE) 0-30%;    (b) vinylidene fluoride (VDF) 50-80%, perfluoroalkylvinylether (PAVE) 5-50%, tetrafluoroethylene (TFE) 0-20%;    (c) vinylidene fluoride (VDF) 20-30%, non fluorinated olefins (Ol) C 2 -C 8  10-30%, hexafluoropropene (HFP) and/or perfluoroalkylvinylether (PAVE) 18-27%, tetrafluoroethylene (TFE) 10-30);    (d) tetrafluoroethylene (TFE) 50-80%, perfluoroalkylvinylether (PAVE) 20-50%;    (e) tetrafluoroethylene (TFE) 45-65%, non fluorinated olefins (Ol) C 2 -C 8  20-55%, vinylidene fluoride 0-30%;    (f) tetrafluoroethylene (TFE) 32-60% by moles, non fluorinated olefins (Ol) C 2 -C 8  10-40%, perfluoroalkylvinylether (PAVE) 20-40%;    (g) tetrafluoroethylene (TFE) 33-75%, perfluoroalkylvinylether (PAVE) 15-45%, vinylidene fluoride (VDF) 5-30%.    
   
   
       40 . Cured fluoropolymers according to  claim 29  wherein the fluoroelastomer comprises also monomer units deriving from a bis-olefin having the formula:  
     
       
         
         
             
             
         
       
     
     wherein 
 R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , equal to or different from each other, are H or alkyl C 1 -C 5 ;  
 Z is a linear or branched, alkylene or cycloalkylene C 1 -C 18  radical, optionally containing oxygen atoms optionally at least partially fluorinated, or a (per)fluoropolyoxyalkylene radical.  
 
   
   
       41 . Cured fluoropolymers according to  claim 40  wherein the unit amount in the chain deriving from the bis-olefin is in the range 0.01-1.0% by moles of the other monomer units forming the fluoroelastomer base structure.  
   
   
       42 . Cured fluoropolymers according to  claim 29  wherein the fluoroelastomers are cured by peroxidic route.  
   
   
       43 . Cured fluoropolymers according to  claim 29  wherein when the fluoroelastomers contain cyano groups they are cured by tin organic compounds and/or di-aromatic aminic compounds.  
   
   
       44 . Cured fluoropolymers according to  claim 29  wherein the fluoroelastomers are cured by tin organic compounds and/or diaromatic aminic compounds and optionally by peroxidic route if in the polymeric chain iodine and/or bromine atoms are present.  
   
   
       45 . Cured fluoropolymers according to  claim 29  wherein the one or more monomers containing at least one unsaturation of ethylene type are present in amounts ranging from 0.5% to 5% by moles.  
   
   
       46 . Cured fluoropolymers according to  claim 36  wherein the perfluoroolefins C 3 -C 8  are selected from the group consisting of hexafluoropropene (HFP) and hexafluoroisobutene.  
   
   
       47 . Cured fluoropolymers according to  claim 36  wherein the hydrogenated fluoroolefins C 2 -C 8  are selected from the group consisting of vinyl fluoride (VF), vinylidene fluoride (VDF), trifluoroethylene and perfluoroalkylethylene CH 2 ═CH—R f , wherein R f  is a perfluoroalkyl C 1 -C 6 .  
   
   
       48 . Cured fluoropolymers according to  claim 36  wherein the chloro-fluoroolefin C 2 -C 8  is chlorotrifluoroethylene (CTFE).  
   
   
       49 . Cured fluoropolymers according to  claim 36  wherein the (per)fluoroalkylvinylethers (PAVE) (CF 2 ═CFOR f ) are selected from the group consisting of CF 3 , C 2 F 5  and C 3 F 7 .  
   
   
       50 . Cured fluoropolymers according to  claim 36  wherein the (per)fluoro-oxyalkyl C 1 -C 12  having one or more ether groups is perfluoro-2-propoxy-propyl.  
   
   
       51 . Cured fluoropolymers according to  claim 38  wherein the perfluoroolefin C 2 -C 8  is selected from the group consisting of tetrafluoroethylene (TFE) and hexafluoropropene (HFP).  
   
   
       52 . Cured fluoropolymers according to  claim 38  wherein the chloro- and/or bromofluoro-olefins C 2 -C 8  are selected from the group consisting of chlorotrifluoroethylene (CTFE) and bromotrifluoroethylene.  
   
   
       53 . Cured fluoropolymers according to  claim 38  wherein the (per)fluoroalkylvinylethers (PAVE) CF 2 ═CFOR f  are selected from the group consisting of trifluoromethyl, bromodifluoromethyl and pentafluoropropyl.  
   
   
       54 . Cured fluoropolymers according to  claim 38  wherein the perfluorooxyalkylvinylether CF 2 ═CFOX is perfluoro-2-propoxy-propyl.  
   
   
       55 . Cured fluoropolymers according to  claim 38  wherein the nonfluorinated olefins (01) C 2 -C 8  are selected from the group consisting of ethylene and propylene.  
   
   
       56 . A sealing manufactured article comprising the cured fluorelastomer of anyone of claims  28 - 54 .  
   
   
       57 . The sealing article according to  claim 56 , wherein the sealing article manufactured article is an O-ring.