Dispersing Agents in Nanocomposites

Abstract

The instant invention discloses a composition, preferably a nanocomposite material, comprising (a) a synthetic polymer, (b) a filler such as for example a natural or synthetic phyllosilicate or a mixture of such phyllosilicates, preferably in nanoparticles, and (c) a dispersing agent prepared by controlled free radical polymerization (CFRP).

1 . A composition comprising
 a) a synthetic polymer,   b) a filler, and   c) a dispersing agent prepared by controlled free radical polymerization (CFRP).   
     
     
         2 . A composition according to  claim 1 , wherein component (a) is a polyolefin. 
     
     
         3 . A composition according to  claim 1 , wherein component (b) is a filler in nanoparticles. 
     
     
         4 . A composition according to  claim 1 , wherein component (b) is a natural or synthetic phyllosilicate or a mixture of such phyllosilicates. 
     
     
         5 . A composition according to  claim 1 , wherein component (b) is a layered silicate clay. 
     
     
         6 . A composition according to  claim 1 , wherein component (b) is a montmorillonite, bentonite, beidelite, mica, hectorite, saponite, nontronite, sauconite, vermiculite, ledikite, magadite, kenyaite, stevensite, volkonskoite, hydrotalcite or a mixture thereof. 
     
     
         7 . A composition according to  claim 1 , wherein component (c) is a random, block, star or comb copolymer prepared by controlled free radical polymerization. 
     
     
         8 . A composition according to  claim 1 , wherein component (c) is a block or comb acrylic co-polymer prepared by controlled free radical polymerization. 
     
     
         9 . A composition according to  claim 1 , wherein component (b) is present in an amount of from 0.1 to 40%, based on the weight of component (a). 
     
     
         10 . A composition according to  claim 1 , wherein component (c) is present in an amount of from 0.1 to 20%, based on the weight of component (a) 
     
     
         11 . A composition according to  claim 1 , comprising in addition, besides components (a), (b) and (c), further additives. 
     
     
         12 . A composition according to  claim 11 , comprising as further additives phenolic antioxidants, light-stabilizers, processing stabilizers, solvents, pigments, dyes, plasticizers, compatibilizers, toughening agents and/or thixotropic agents. 
     
     
         13 . A composition according to  claim 1  in the form of a masterbatch or concentrate comprising component (a) in an amount of from 5 to 90%, component (b) in an amount of from 5 to 80%, and component (c) in an amount of from 0.5 to 50% by weight. 
     
     
         14 . A process for the preparation of a synthetic polymer nanocomposite material which comprises melt mixing a mixture of a) a synthetic polymer, b) a filler, and c) a dispersing agent prepared by controlled free radical polymerization (CFRP). 
     
     
         15 . A process according to  claim 14 , wherein the melt mixing occurs between 120 and 290° C. 
     
     
         16 . A synthetic polymer nanocomposite obtained by a process according to  claim 14 . 
     
     
         17 . A method to exfoliate a filler and disperse the filler in a synthetic polymer matrix to form a nanocomposite material, which comprises melt mixing a mixture of a) a synthetic polymer, b) a filler, and c) an effective dispersing amount of a dispersing agent prepared by controlled free radical polymerization and then forming the nanocomposite material.