Methods and systems for polymer precipitation and generation of particles

Abstract

Processes for precipitating a polymer from a polymer-containing fluid are disclosed, which include providing a vessel housing a medium that provides one or more precipitation surfaces. A polymer-containing fluid, e.g., a polymer solution, dispersion or mixed solution/dispersion, and an anti-solvent can be introduced into the vessel so as to cause precipitation of at least a portion of the polymer on at least one of the precipitation surfaces. In some embodiments, the polymer contains one or more cyclic oligosaccharide moieties, such as one or more cyclodextrin moieties (e.g., α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin). The polymer can be any of a linear or branched polymer. The polymer can be any of polycation, a polyanion, or a non-ionic polymer. Also disclosed herein are precipitation surfaces with polymer precipitated thereon.

1 . A process for precipitating a polymer from a polymer-containing fluid, comprising: providing a vessel housing a medium, the medium providing one or more precipitation surfaces, introducing a polymer-containing fluid and an anti-solvent into the vessel so as to cause precipitation of at least a portion of the polymer on at least one of said precipitation surfaces,
 wherein the polymer contains one or more cyclic oligosaccharide moieties.   
     
     
         2 . The process of  claim 1  wherein the process further comprises extracting at least a portion of the polymer-containing fluid and the anti-solvent from the vessel and recirculating the mixture thorough the vessel and medium to induce further precipitation. 
     
     
         3 . The process of  claim 1 , wherein said medium is porous. 
     
     
         4 . The process of  claim 3 , wherein said porous medium comprises a mesh. 
     
     
         5 . The process of  claim 3 , wherein said porous medium comprises a plurality of insoluble supports providing said precipitation surfaces. 
     
     
         6 . The process of  claim 4 , wherein said mesh is formed at least partially of a metal. 
     
     
         7 . The process of  claim 6 , wherein said metal comprises any of stainless steel, gold and silver. 
     
     
         8 . The process of  claim 4 , wherein said mesh is formed at least partially of a polymeric material. 
     
     
         9 . The process of  claim 8 , wherein said polymeric material comprises polytetrafluoroethylene (PTFE). 
     
     
         10 . The process of  claim 5 , wherein said insoluble supports having said precipitation surfaces exhibit a size in a range of about 10 microns to about 1 millimeter. 
     
     
         11 . The process of  claim 5 , wherein said insoluble supports having said precipitation surfaces exhibit a size in a range of about 10 microns to about 200 microns. 
     
     
         12 . The process of  claim 5 , wherein said insoluble supports having said precipitation surfaces comprise a powder of diatomaceous earth. 
     
     
         13 . The process of  claim 1 , wherein said medium is inert to any of said anti-solvent, said polymer-containing fluid, and said polymer. 
     
     
         14 . The process of  claim 1 , wherein said polymer in said polymer-containing fluid has an average molecular weight between 50 kDa and 100 kDa. 
     
     
         15 . The process of  claim 14 , wherein said polymer has an average molecular weight in a range of about 70 kDa to about 80 kDa. 
     
     
         16 . The process of  claim 1 , further introducing at least a portion of said anti-solvent into said vessel prior to the introduction of the polymer-containing fluid into the vessel. 
     
     
         17 . The process of  claim 16 , further comprising agitating said anti-solvent present in the vessel and introducing said polymer-containing fluid into the agitated anti-solvent. 
     
     
         18 . The process of  claim 1 , further comprising causing a flow of the anti-solvent through said vessel. 
     
     
         19 . The process of  claim 18 , wherein the polymer-containing fluid is introduced into said flowing anti-solvent. 
     
     
         20 . The process of  claim 1 , wherein the polymer in said polymer-containing fluid is immiscible in said anti-solvent. 
     
     
         21 - 178 . (canceled)