Polymerisation process and polymer product

Abstract

A method of polymerising monomer to form polymer at the surface of particulate material, said method comprising: providing a dispersion of said particulate material in a continuous liquid phase, said dispersion comprising a RAFT agent as a stabiliser for said particulate material, and said continuous liquid phase comprising one or more ethylenically unsaturated monomers; and polymerising said one or more ethylenically unsaturated monomers under the control of said RAFT agent to thereby form polymer at the surface of said particulate material.

1 . A method of polymerising monomer to form polymer at the surface of particulate material, said method comprising:
 providing a dispersion of said particulate material in a continuous liquid phase, said dispersion comprising a RAFT agent as a stabiliser for said particulate material, and said continuous liquid phase comprising one or more ethylenically unsaturated monomers; and   polymerising said one or more ethylenically unsaturated monomers under the control of said RAFT agent to thereby form polymer at the surface of said particulate material.   
     
     
         2 . The method according to  claim 1 , wherein the dispersion of said particulate material is prepared by forming a composition comprising the particulate material, the RAFT agent and the continuous liquid phase, and the one or more ethylenically unsaturated monomers are then added to the composition and polymerised under the control of the RAFT agent to thereby form polymer at the surface of the particulate material. 
     
     
         3 . The method according to  claim 1 , wherein the dispersion of said particulate material is prepared by forming a composition comprising the particulate material, the RAFT agent and the one or more ethylenically unsaturated monomers as the continuous liquid phase, and wherein said composition is dispersed in a second continuous liquid phase and the one or more ethylenically unsaturated monomers which form the first mentioned continuous liquid phase are polymerised under the control of the RAFT agent to thereby form polymer at the surface of the particulate material. 
     
     
         4 . The method according to  claim 2 , wherein the continuous liquid phase is water. 
     
     
         5 . The method according to  claim 3 , wherein the second continuous liquid phase is water. 
     
     
         6 . A method of preparing a dispersion of polymer encapsulated particulate material in a liquid, said method comprising:
 providing a dispersion of particulate material in a continuous liquid phase, said dispersion comprising a RAFT agent as a stabiliser for said particulate material, and said continuous liquid phase comprising one or more ethylenically unsaturated monomers; and   polymerising said one or more ethylenically unsaturated monomers under the control of said RAFT agent to form polymer at the surface of said particulate material, thereby providing said dispersion of polymer encapsulated particulate material in a liquid.   
     
     
         7 . The method according to  claim 6 , wherein the continuous liquid phase is water and the method provides an aqueous dispersion of polymer encapsulated particulate material. 
     
     
         8 . A method of preparing a polymer having particulate material dispersed therethrough, said method comprising:
 providing a dispersion of said particulate material in a continuous liquid phase, said dispersion comprising a RAFT agent as a stabiliser for said particulate material, and said continuous liquid phase consisting essentially of one or more ethylenically unsaturated monomers; and   polymerising said one or more ethylenically unsaturated monomers under the control of said RAFT agent to form polymer at the surface of said particulate material, thereby providing polymer having the particulate material dispersed therethrough.   
     
     
         9 . The method according to  claim 8 , wherein the continuous liquid phase comprising the particulate material and the RAFT agent is dispersed in a second continuous liquid phase, and wherein the one or more ethylenically unsaturated monomers are polymerised under the control of the RAFT agent to form polymer at the surface of said particulate material to thereby provide a dispersion in the second continuous liquid phase of polymer particles having the particulate material dispersed therethrough. 
     
     
         10 . A method of preparing a paint, thermofusable powder paint, filler, adhesive, toner, liquid ink, primer, sealant, diagnostic product or therapeutic product comprising preparing a dispersion of polymer encapsulated particulate material according to  claim 6 , and combining said dispersion and/or polymer with one or more formulation components. 
     
     
         11 . A paint, thermofusable powder paint, filler, adhesive, toner, liquid ink, primer, sealant, diagnostic product or therapeutic product comprising a dispersion of polymer encapsulated particulate material prepared in accordance with  claim 6 . 
     
     
         12 . The method according to any one of  claim 1 , wherein the particulate material is a solid. 
     
     
         13 . The method according to  claim 12 , wherein the solid is selected from inorganic pigments, organic pigments, titanium dioxide, zinc oxide, calcium carbonate, iron oxide, silicone dioxide, barium sulfate, carbon black, phthalocyanine blue, phtalocyanine green, quinacridone, dibromananthrone, magnetic material, waxes, bioactive agents, and combinations thereof. 
     
     
         14 . The method according to any one of  claim 1 , wherein the largest dimension of the particulate material is no greater than 10 microns. 
     
     
         15 . The method according to  claim 14 , wherein the largest dimension of the particulate material is no greater than 1 micron. 
     
     
         16 . Polymer encapsulated particulate material that is 100 microns or less in size, said particulate material being encapsulated in a substantially uniform and continuous coating of a polymer which has at least in part been formed under the control of a RAFT agent. 
     
     
         17 . Polymer encapsulated particulate material that is 100 microns or less in size, wherein the polymer which encapsulates the particulate material has at least in part been formed under the control of a RAFT agent, and wherein the particulate material is substantially uniformly dispersed throughout the polymer. 
     
     
         18 . A composition comprising or consisting of discrete particles of polymer encapsulated particulate material, said particulate material being encapsulated in a substantially uniform and continuous coating of a polymer which has at least in part been formed under the control of a RAFT agent. 
     
     
         19 . A composition comprising or consisting of discrete particles of polymer encapsulated particulate material, said discrete particles having the particulate material substantially uniformly dispersed throughout the encapsulating polymer, wherein the encapsulating polymer has at least in part been formed under the control of a RAFT agent, and wherein the discrete particles are substantially free of additional dispersant for the particulate material. 
     
     
         20 . The composition according to  claim 18  which is in the form of a free flowing powder. 
     
     
         21 . A paint, thermofusable powder paint, filler, adhesive, primer, toner, liquid ink, sealant, diagnostic product or therapeutic product comprising a composition according to  claim 18 . 
     
     
         22 . A liquid dispersion of polymer encapsulated particulate material, said particulate material being encapsulated in a substantially uniform and continuous coating of a polymer which has at least in part been formed under the control of a RAFT agent. 
     
     
         23 . A liquid dispersion of polymer encapsulated particulate material, said polymer encapsulated particulate material having the particulate material substantially uniformly dispersed throughout the encapsulating polymer, wherein the encapsulating polymer has at least in part been formed under the control of a RAFT agent, and wherein the polymer encapsulated particulate material is substantially free of additional dispersant for the particulate material. 
     
     
         24 . The liquid dispersion according to  claim 22 , wherein the liquid is water. 
     
     
         25 . The method according to  claim 1 , wherein the RAFT agent is of general formula (4): 
       
         
           
           
               
               
           
         
         where each X is independently a polymerised residue of an ethylenically unsaturated monomer, n is an integer ranging from 0 to 100, R1 is an organic group optionally substituted with one or more hydrophilic groups and Z is any group that can promote sufficient reactivity of the thiocarbonyl group towards radical additional while not slowing the rate of fragmentation to the extent that there is unacceptable retardation of polymerisation. 
       
     
     
         26 . A method of preparing a paint, thermofusable powder paint, filler, adhesive, toner, liquid ink, primer, sealant, diagnostic product or therapeutic product comprising preparing a polymer having particulate material dispersed therethrough according to  claim 8 , and combining said dispersion and/or polymer with one or more formulation components. 
     
     
         27 . A paint, thermofusable powder paint, filler, adhesive, toner, liquid ink, primer, sealant, diagnostic product or therapeutic product comprising a polymer having particulate material dispersed therethrough prepared in accordance with  claim 8 . 
     
     
         28 . The polymer encapsulated particulate material according to  claim 16 , wherein the RAFT agent is of general formula (4): 
       
         
           
           
               
               
           
         
         where each X is independently a polymerised residue of an ethylenically unsaturated monomer, n is an integer ranging from 0 to 100, R1 is an organic group optionally substituted with one or more hydrophilic groups and Z is any group that can promote sufficient reactivity of the thiocarbonyl group towards radical additional while not slowing the rate of fragmentation to the extent that there is unacceptable retardation of polymerisation. 
       
     
     
         29 . The composition according to  claim 18 , wherein the RAFT agent is of general formula (4): 
       
         
           
           
               
               
           
         
         where each X is independently a polymerised residue of an ethylenically unsaturated monomer, n is an integer ranging from 0 to 100, R1 is an organic group optionally substituted with one or more hydrophilic groups and Z is any group that can promote sufficient reactivity of the thiocarbonyl group towards radical additional while not slowing the rate of fragmentation to the extent that there is unacceptable retardation of polymerisation. 
       
     
     
         30 . The paint, thermofusable powder paint, filler, adhesive, primer, toner, liquid ink, sealant, diagnostic product or therapeutic product according to  claim 21 , wherein the RAFT agent is of general formula (4): 
       
         
           
           
               
               
           
         
         where each X is independently a polymerised residue of an ethylenically unsaturated monomer, n is an integer ranging from 0 to 100, R1 is an organic group optionally substituted with one or more hydrophilic groups and Z is any group that can promote sufficient reactivity of the thiocarbonyl group towards radical additional while not slowing the rate of fragmentation to the extent that there is unacceptable retardation of polymerisation. 
       
     
     
         31 . The liquid dispersion according to  claim 22 , wherein the RAFT agent is of general formula (4): 
       
         
           
           
               
               
           
         
         where each X is independently a polymerised residue of an ethylenically unsaturated monomer, n is an integer ranging from 0 to 100, R1 is an organic group optionally substituted with one or more hydrophilic groups and Z is any group that can promote sufficient reactivity of the thiocarbonyl group towards radical additional while not slowing the rate of fragmentation to the extent that there is unacceptable retardation of polymerisation.