Block copolymer based on conjugated diolefins and polar monomers

Abstract

The block copolymers according to the invention which are based on conjugated diolefins and polar monomers and are prepared in the presence of catalysts based on the rare earth metals have a high cis-1,4 content in the polydiene block and, because of their polar polymer part and their non-polar diene polymer part, can be used as agents which impart compatibility in the preparation of vulcanizates with a filler content for the production of tires and tire components, as a filler in the preparation of such vulcanizates, and as a blend component in the preparation of thermoplastic elastomers or in the modification of thermoplastics.

What is claimed is:  
     
         1 . Block copolymers based on conjugated dienes and polar monomers, wherein the block copolymers comprise the polymerized conjugated dienes in amounts of 5 to 95 wt. % and the polymerized polar monomers in amounts of 95 to 5 wt. %, the polymerized dienes having a cis-1,4 content of ≧60 wt. %.  
     
     
         2 . Block copolymers according to  claim 1 , wherein said conjugated dienes are selected from the group consisting of 1,3-butadiene, 1,3-isoprene, 2,3-dimethylbutadiene, 2,4-hexadiene, 1,3-pentadiene and/or 2-methyl-1,3-pentadiene.  
     
     
         3 . Block copolymers according to  claim 1 , wherein said polar monomers are selected from the group consisting of lactones, lactams, thiolactams, epoxides, cyclic sulfides and cyclic carbonates.  
     
     
         4 . Block copolymers according to  claim 3 , wherein said polar monomers are selected from the group consisting of ε-caprolactone, γ-valerolactone, δ-valerolactone, γ-butyrolactone and/or β-butyrolactone.  
     
     
         5 . A process for the preparation of block copolymers based on conjugated dienes- and polar monomers, wherein the block copolymers comprise the polymerized conjugated dienes in amounts of 5 to 95 wt. % and the polymerized polar monomers in amounts of 95 to 5 wt. %, the polymerized dienes having a cis-1,4 content of ≧60 wt. %.  
       comprising the steps of 
 (i) polymerizing the conjugated dienes in the presence of catalysts comprising  
 (A) at least one compound of the rare earth metals,  
 (B) at least one organoaluminum compound and  
 (C) at least one Lewis acid  
 and in the presence of inert organic solvents up to a conversion of ≧50 wt. %;  
 (ii) adding the polar monomers to the polymerization mixture and polymerization is carried out up to a conversion of ≧30 wt. % and  
 (iii) isolating the resulting block copolymer, and  
 (iv) employing the conjugated dienes in the reaction mixture in amounts of 5 to 30 wt. % and the polar monomers in amounts of 1 to 30 wt. %.  
 
     
     
         6 . The process according to  claim 5 , wherein said conjugated dienes are selected from the group consisting of 1,3-butadiene, 1,3-isoprene, 2,3-dimethylbutadiene, 2,4-hexadiene, 1,3-pentadiene and 2-methyl-1,3-pentadiene.  
     
     
         7 . The process according to  claim 5 , wherein said polar monomers are selected from the group consisting of lactones, lactams, thiolactams, epoxides, cyclic sulfides and cyclic carbonates.  
     
     
         8 . The process according to  claim 7 , wherein polar monomers are selected from the group consisting of ε-caprolactone, γ-valerolactone, δ-valerolactone, γ-butyrolactone and/or β-butyrolactone.  
     
     
         9 . The process according to  claim 5 , wherein the compounds of the rare earth metals which are employed are their alcoholates, phosphonates, phosphinates, phosphates and carboxylates and the complex compounds of the rare earth metals with diketones, the addition compounds of the halides of the rare earth metals with an oxygen or nitrogen donor compound and allyl compounds of the rare earth metals.  
     
     
         10 . The process according to  claim 9 , wherein said compounds of the rare earth metals are selected from the group consisting of neodymium versatate, neodymium octanoate and neodymium naphthenate.  
     
     
         11 . The process according to  claim 5 , wherein said organoaluminum compound is selected from the group consisting of aluminumtrialkyl, dialkylaluminum hydride and alumoxanes.  
     
     
         12 . The process according to  claim 5 , wherein said Lewis acid is organometallic halides of group IIIA and IVA and/or halides of elements of group IIIA, IVA and VA of the periodic table.  
     
     
         13 . The process according to  claim 5 , wherein said inert solvents are aliphatic or aromatic solvents.  
     
     
         14 . The process according to  Claim 13  wherein said aliphatic solvents are selected from the group consisting of butane, pentane, hexane or heptane or said aromatic solvents are selected from the group consisting of benzene, toluene, ethylbenzene or dimethylbenzene or mixtures.  
     
     
         15 . Vulcanizates with a filler content for the production of tires and tire components comprising block copolymers based on conjugated dienes and polar monomers, wherein the block copolymers comprise the polymerized conjugated dienes in amounts of 5 to 95 wt. % and the polymerized polar monomers in amounts of 95 to 5 wt. %, the polymerized dienes having a cis-1,4 content of ≧60 wt. %.  
     
     
         16 . A thermoplastic elastomer containing block copolymers based on conjugated dienes and polar monomers which comprise the polymerized conjugated dienes in amounts of 5 to 95 wt. % and the polymerized polar monomers in amounts of 95 to 5 wt. %, the polymerized dienes having a cis-1,4 content of ≧60 wt. %.  
     
     
         17 . A blend material for the modification of thermoplastics comprising block copolymers based on conjugated dienes and polar monomers which comprise the polymerized conjugated dienes in amounts of 5 to 95 wt. % and the polymerized polar monomers in amounts of 95 to 5 wt. %, the polymerized dienes having a cis-1,4 content of ≧60 wt. %.