Method of producing structures using centrifugal forces

Abstract

A variety of hollow structures with unique morphologies were manufactured with a rotational spinning technique. Phase separation of soluble solutions was induced within a filled mold as it was being rotated about one of its axis. As phase-separation occurs within this rotating mold, the increase in density of one phase results in sediment at the periphery under centrifugal forces. After or during sedimentation, gelation of the phase-separated particles fixes the tube morphology and the solvent remains in the center of the mold. The solvent is removed from the mold resulting in a tube. By controlling the rotational speed and the formulation chemistry, the tube dimensions and wall morphology can be manipulated. This technique offers a new approach to the manufacture of polymeric tubes. It requires small quantities of starting material, permits multi-layering of tubes, is applicable to diverse polymers and can result in highly diffusive hollow structures while maintaining good mechanical strength.

1 .- 21 . (cancelled)  
     
     
         22 . A product produced by a method comprising the steps of: 
 filling an interior of a mold with a solution so that substantially all air is displaced therefrom, the solution comprising at least two components which can be phase separated by a phase separation agent into at least two phases;    rotating said mold containing said solution at an effective rotational velocity in the presence of said phase separation agent to induce phase separation between said at least two components into at least two phases so that under rotation at least one of the phases deposits onto an inner surface of the mold; and    forming said product by stabilizing said at least one of the phases deposited onto the inner surface of the mold.    
     
     
         23 . The product according to  claim 22  including removing said product from said mold.  
     
     
         24 . The product according to  claim 22  wherein said hollow mold is a cylindrical tube so that said product is a tube.  
     
     
         25 . The product according to  claim 22  wherein said at least two components includes at least one monomer and at least one solvent, and wherein said solution is a substantially homogenous solution, wherein said at least one of the phases that deposits onto the inner surface includes at least the monomer, and wherein the step of stabilizing said deposited phase includes gelation of the monomer by polymerization thereof, wherein said product is a polymeric product.  
     
     
         26 . The product according to  claim 22  wherein said at least two components includes at least one polymer dissolved in at least one solvent, and wherein said solution is a substantially homogenous solution, wherein said at least one of the phases that deposits on the inner surface includes at least the polymer, and wherein the step of stabilizing said deposited phase includes gelation thereof, wherein said product is a polymeric product.  
     
     
         27 . The product according to  claim 25  wherein the product has a wall morphology that includes a porous structure, a gel structure or overlapping regions of porous/gel structure.  
     
     
         28 . The product according to  claim 25  wherein the product has a wall morphology that includes a predominantly gel morphology with porous channels running from a periphery to a lumenal side, resulting in spotting on an outer wall surface.  
     
     
         29 . The product according to  claim 22  wherein said product is a multi-layered product produced by repeating steps a), b) and c), at least once to produce a multi-layered product.  
     
     
         30 . The product according to  claim 25  wherein the wall structure is used as a reservoir for the delivery of drugs, therapeutics, cells, cell products, genes, viral vectors, proteins, peptides, hormones, carbohydrates, growth factors.  
     
     
         31 . The product according to  claim 25  wherein the solution contains microspheres containing preselected constituents, and wherein the product includes said microspheres distributed either uniformly or in a gradient within the wall structure of the product.  
     
     
         32 . The product according to  claim 23  wherein said hollow mold is a cylindrical tube so that said product is a tube.  
     
     
         33 . The product according to  claim 24  wherein said tube has an internal diameter in a range from about 10 μm to about 100 cm.  
     
     
         34 . The product according to  claim 32  wherein said tube has an internal diameter in a range from about 10 μm to about 100 cm.  
     
     
         35 . The product according to  claim 23  wherein said at least two components includes at least one monomer and at least one solvent, and wherein said solution is a substantially homogenous solution, wherein said at least one of the phases that deposits onto the inner surface includes at least the monomer, and wherein the step of stabilizing said deposited phase includes gelation of the monomer by polymerization thereof, wherein said product is a polymeric product.  
     
     
         36 . The product according to  claim 24  wherein said at least two components includes at least one monomer and at least one solvent, and wherein said solution is a substantially homogenous solution, wherein said at least one of the phases that deposits onto the inner surface includes at least the monomer, and wherein the step of stabilizing said deposited phase includes gelation of the monomer by polymerization thereof, wherein said product is a polymeric product.  
     
     
         37 . The product according to  claim 23  wherein said at least two components includes at least one polymer dissolved in at least one solvent, and wherein said solution is a substantially homogenous solution, wherein said at least one of the phases that deposits on the inner surface includes at least the polymer, and wherein the step of stabilizing said deposited phase includes gelation thereof, wherein said product is a polymeric product.  
     
     
         38 . The product according to  claim 24  wherein said at least two components includes at least one polymer dissolved in at least one solvent, and wherein said solution is a substantially homogenous solution, wherein said at least one of the phases that deposits on the inner surface includes at least the polymer, and wherein the step of stabilizing said deposited phase includes gelation thereof, wherein said product is a polymeric product.  
     
     
         39 . The product according to  claim 26  wherein the product has a wall morphology that includes a porous structure, a gel structure or overlapping regions of porous/gel structure.  
     
     
         40 . The product according to  claim 35  wherein the product has a wall morphology that includes a porous structure, a gel structure or overlapping regions of porous/gel structure.  
     
     
         41 . The product according to  claim 36  wherein the product has a wall morphology that includes a porous structure, a gel structure or overlapping regions of porous/gel structure.  
     
     
         42 . The product according to  claim 37  wherein the product has a wall morphology that includes a porous structure, a gel structure or overlapping regions of porous/gel structure.  
     
     
         43 . The product according to  claim 38  wherein the product has a wall morphology that includes a porous structure, a gel structure or overlapping regions of porous/gel structure.  
     
     
         44 . The product according to  claim 26  wherein the product has a wall morphology that includes a predominantly gel morphology with porous channels running from a periphery to a lumenal side, resulting in spotting on an outer wall surface.  
     
     
         45 . The product according to  claim 35  wherein the product has a wall morphology that includes a predominantly gel morphology with porous channels running from a periphery to a lumenal side, resulting in spotting on an outer wall surface.  
     
     
         46 . The product according to  claim 36  wherein the product has a wall morphology that includes a predominantly gel morphology with porous channels running from a periphery to a lumenal side, resulting in spotting on an outer wall surface.  
     
     
         47 . The product according to  claim 37  wherein the product has a wall morphology that includes a predominantly gel morphology with porous channels running from a periphery to a lumenal side, resulting in spotting on an outer wall surface.  
     
     
         48 . The product according to  claim 38  wherein the product has a wall morphology that includes a predominantly gel morphology with porous channels running from a periphery to a lumenal side, resulting in spotting on an outer wall surface.  
     
     
         49 . The product according to  claim 26  wherein the wall structure is used as a reservoir for the delivery of drugs, therapeutics, cells, cell products, genes, viral vectors, proteins, peptides, hormones, carbohydrates, growth factors.  
     
     
         50 . The product according to  claim 35  wherein the wall structure is used as a reservoir for the delivery of drugs, therapeutics, cells, cell products, genes, viral vectors, proteins, peptides, hormones, carbohydrates, growth factors.  
     
     
         51 . The product according to  claim 36  wherein the wall structure is used as a reservoir for the delivery of drugs, therapeutics, cells, cell products, genes, viral vectors, proteins, peptides, hormones, carbohydrates, growth factors.  
     
     
         52 . The product according to  claim 37  wherein the wall structure is used as a reservoir for the delivery of drugs, therapeutics, cells, cell products, genes, viral vectors, proteins, peptides, hormones, carbohydrates, growth factors.  
     
     
         53 . The product according to  claim 38  wherein the wall structure is used as a reservoir for the delivery of drugs, therapeutics, cells, cell products, genes, viral vectors, proteins, peptides, hormones, carbohydrates, growth factors.  
     
     
         54 . The product according to  claim 26  wherein the solution contains microspheres containing preselected constituents, and wherein the product includes said microspheres distributed either uniformly or in a gradient within the wall structure of the product.  
     
     
         55 . The product according to  claim 35  wherein the solution contains microspheres containing preselected constituents, and wherein the product includes said microspheres distributed either uniformly or in a gradient within the wall structure of the product.  
     
     
         56 . The product according to  claim 36  wherein the solution contains microspheres containing preselected constituents, and wherein the product includes said microspheres distributed either uniformly or in a gradient within the wall structure of the product.  
     
     
         57 . The product according to  claim 37  wherein the solution contains microspheres containing preselected constituents, and wherein the product includes said microspheres distributed either uniformly or in a gradient within the wall structure of the product.  
     
     
         58 . The product according to  claim 38  wherein the solution contains microspheres containing preselected constituents, and wherein the product includes said microspheres distributed either uniformly or in a gradient within the wall structure of the product.  
     
     
         59 . The product according to  claim 22  wherein said product is a multi-layered product produced by repeating steps a), b) and c), at least once to produce a multi-layered product.  
     
     
         60 . The product according to  claim 23  wherein said product is a multi-layered product produced by repeating steps a), b) and c), at least once to produce a multi-layered product.  
     
     
         61 . The product according to  claim 24  wherein said product is a multi-layered product produced by repeating steps a), b) and c), at least once to produce a multi-layered product.  
     
     
         62 . The product according to  claim 25  wherein said product is a multi-layered product produced by repeating steps a), b) and c), at least once to produce a multi-layered product.  
     
     
         63 . The product according to  claim 26  wherein said product is a multi-layered product produced by repeating steps a), b) and c), at least once to produce a multi-layered product.