Tubes having internal diameters in the nanometer range

Abstract

Hollow fibers having an internal diameter from 1 nm to 100 nm can be produced by coating degradable materials with nondegradable materials and then degrading the degradable materials. The hollow fibers are useful in separation technology, catalysis, microelectronics, medical technology, materials technology or the clothing industry.

1 . A hollow fiber having an internal diameter from 1 nm to 100 nm and an outer wall comprising a metal-containing inorganic compound, a polymer, a metal or a combination thereof.  
     
     
         2 . The hollow fiber according to  claim 1 , wherein said internal diameter is from 1 nm to 10 nm.  
     
     
         3 . The hollow fiber according to  claim 1 , wherein said outer wall comprises a homopolymer, a copolymer or a blend of compounds selected from the group consisting of poly(p-xylylene), polyacrylamide, polyimides, polyesters, polyolefins, polycarbonates, polyamides, polyethers, polyphenylene, polysilanes, polysiloxanes, polybenzimidazoles, polybenzothiazoles, polyoxazoles, polysulfides, polyester, amides, polyarylenevinylenes, polylactides, polyether ketones, polyurethanes, polysulfones, ormocers, polyacrylates, silicones, aromatic copolyesters, poly-N-vinylpyrrolidone, polyhydroxyethyl methacrylate, polymethyl methacrylate, polyethylene terephthalate, polybutylene terephthalate, polymethacrylonitrile, polyacrylonitrile, polyvinyl acetate, neoprene, Buna N, polybutadiene, polytetrafluoroethene, modified cellulose, unmodified cellulose, alginates, and collagen.  
     
     
         4 . The hollow fiber according to  claim 1 , wherein said outer wall comprises a metal or an alloy of metals selected from the group consisting of metals of groups Ia, Ib, Ia, IIb, IIIa, IIIb, IVa, IVb, Vb, VIb, VIb, VIIb of the periodic table, and mixtures thereof.  
     
     
         5 . The hollow fiber according to  claim 1 , wherein said outer wall comprises glass, glass ceramics, SIO x , perovskite, ceramics, aluminas or zirconias.  
     
     
         6 . The hollow fiber according to  claim 1 , wherein said outer wall comprises a plurality of layers.  
     
     
         7 . The hollow fiber according to  claim 1 , having a dielectric constant of less than  4 .  
     
     
         8 . A process for preparing a hollow fiber, comprising: 
 coating a fiber of a first, degradable material with at least one coating of at least one second material; and    degrading the first, degradable material to obtain the hollow fiber;    wherein said hollow fiber has an internal diameter from 1 nm to 100 nm.    
     
     
         9 . The process according to  claim 8 , wherein the first, degradable material comprises 10-60% by weight of a noble metal salt.  
     
     
         10 . The process according to  claim 8 , wherein the first, degradable material further comprises a basic compound.  
     
     
         11 . The process according to  claim 8 , wherein the second material comprises an inorganic compound, a polymer, a metal or a mixture thereof.  
     
     
         12 . The process according to  claim 8 , wherein the second material comprises homopolymers, copolymer or blends of compounds selected from the group consisting of poly(p-xylylene), polyacrylamide, polyimides, polyesters, polyolefins, polycarbonates, polyamides, polyethers, polyphenylene, polysilanes, polysiloxanes, polybenzimidazoles, polybenzothazoles, polyoxazoles, polysulfides, polyester amides, polyarylenevinylenes, polylactides, polyether ketones, polyurethanes, polysulfones, ormocers, polyacrylates, silicones, aromatic copolyesters, poly-N-vinylpyrrolidone, polyhydroxyethyl methacrylate, polymethyl methacrylate, polyethylene terephthalate, polybutylene terephthalate, polymethacrylonitrile, polyacrylonitrile, polyvinyl acetate, neoprene, Buna N, polybutadiene, polytetrafluoroethene, modified cellulose, unmodified cellulose, alginates, and collagen.  
     
     
         13 . The process according to  claim 8 , wherein the second material comprises a metal or an alloy of metals selected from the group consisting of metals of groups Ia, Ib, Ia, IIb, IIa, IIIb, IVa, IVb, Vb, VIb, VIb, VIIb of the periodic table, and mixtures thereof.  
     
     
         14 . The process according to  claim 8 , wherein the second material comprises metal oxides, glass, glass ceramics SiO x , perovskite, ceramics, aluminas, silicon carbide, boron nitride, carbon or zirconias.  
     
     
         15 . The process according to  claim 8 , wherein the second material is obtained by polymerization of one or more monomers.  
     
     
         16 . The process according to  claim 15 , wherein the second material is obtained by homopolymerization or copolymerization of a compound selected from the group consisting of methacrylate, styrene, styrene sulfonate, 1,6-hexamethylene diusocyanate, 4,4′-methylenebiscyclohexyl dilsocyanate, 4,4′-methylenebis(benzyl-diisocyanate), 1,4butanediol, ethylenediamine, ethylene, styrene, butadiene, 1-butene, 2-butene, vinyl alcohol, acrylonitrile, methyl methacrylate, vinyl chloride, fluorinated ethylenes, terephthalate or mixtures thereof.  
     
     
         17 . The process according to  claim 8 , wherein the degrading of the first, degradable material is effected thermally, chemically, biologically, radiation-induced, photochemically, by plasma, by ultrasound or by extraction with a solvent.  
     
     
         18 . A separation medium or storage medium for gases, liquids or particle suspensions, comprising: 
 the hollow fiber according to  claim 1 .    
     
     
         19 . A method for removal of a metabolite or an enzyme from cytoplasm, comprising: 
 contacting said cytoplasm with the hollow fiber according to  claim 1.