Abstract: This invention relates to an osmotically compacted polyelectrolyte complex having a first region and a second region, the first region having a greater modulus than the second region and a method for preparing such an article. The article comprising the polyelectrolyte complex is produced by contacting a polyelectrolyte complex with a solution comprising an osmolyte at a concentration sufficient to compact the polyelectrolyte complex. The compaction process is terminated before the entire article is osmotically compacted.

Abstract: A method of reshaping an article comprising a polyelectrolyte complex, the polyelectrolyte complex comprising an intermolecular blend of a predominantly positively-charged polyelectrolyte and a predominantly negatively charged polyelectrolyte by controlling the salt doping level.

Abstract: A method of reshaping an article comprising a polyelectrolyte complex, the polyelectrolyte complex comprising an intermolecular blend of a predominantly positively-charged polyelectrolyte and a predominantly negatively charged polyelectrolyte by controlling the salt doping level.

Abstract: A method is described for producing an osmotically compacted polyelectrolyte complex having a first region and a second region, the first region having a greater modulus than the second region. The method comprises contacting an article comprising polyelectrolyte complex to a solution comprising a preferred osmolyte of concentration sufficient to compact said polyelectrolyte complex and terminating the compaction process before the entire article is osmotically compacted. A method is also described for producing a article comprising water and an intermolecular blend of at least one positively charged polyelectrolyte polymer and at least one negatively charged polymer, said article having a core region and a surface region, the surface region having at least twice the elastic modulus of the core region, the method comprising contacting a starting article comprising a blend of said polymers with a solution of osmolyte, wherein the osmolyte is excluded from said article.

Abstract: An article comprising a polyelectrolyte complex, the polyelectrolyte complex comprising an intermolecular blend of a predominantly positively-charged polyelectrolyte and a predominantly negatively charged polyelectrolyte and being free of salt crystals having a size greater than about 1 micrometer and free of voids having a size greater than about 100 nm, the article having no transverse dimension less than about 10,000 nm.

Abstract: A method of reshaping an article comprising a polyelectrolyte complex, the polyelectrolyte complex comprising an intermolecular blend of a predominantly positively-charged polyelectrolyte and a predominantly negatively charged polyelectrolyte by controlling the salt doping level.

Abstract: An article comprising a polyelectrolyte complex comprising an interpenetrating network of at least one predominantly positively charged polyelectrolyte polymer and at least one predominantly negatively charged polyelectrolyte polymer, the polyelectrolyte complex further comprising a plurality of closed-shell pores, the plurality of pores having at least one average transverse dimension between about 100 nanometer and about 1000 micrometers.

Abstract: A method is described for producing an osmotically compacted polyelectrolyte complex having a first region and a second region, the first region having a greater modulus than the second region. The method comprises contacting an article comprising polyelectrolyte complex to a solution comprising a preferred osmolyte of concentration sufficient to compact said polyelectrolyte complex and terminating the compaction process before the entire article is osmotically compacted. A method is also described for producing a article comprising water and an intermolecular blend of at least one positively charged polyelectrolyte polymer and at least one negatively charged polymer, said article having a core region and a surface region, the surface region having at least twice the elastic modulus of the core region, the method comprising contacting a starting article comprising a blend of said polymers with a solution of osmolyte, wherein the osmolyte is excluded from said article.

Abstract: A method is described for producing an osmotically compacted polyelectrolyte complex having a first region and a second region, the first region having a greater modulus than the second region. The method comprises contacting an article comprising polyelectrolyte complex to a solution comprising a preferred osmolyte of concentration sufficient to compact said polyelectrolyte complex and terminating the compaction process before the entire article is osmotically compacted. A method is also described for producing a article comprising water and an intermolecular blend of at least one positively charged polyelectrolyte polymer and at least one negatively charged polymer, said article having a core region and a surface region, the surface region having at least twice the elastic modulus of the core region, the method comprising contacting a starting article comprising a blend of said polymers with a solution of osmolyte, wherein the osmolyte is excluded from said article.

Abstract: A method for controlling the hydrophobicity of a surface of an article by alternately depositing solutions comprising net positively charged polymers and net negatively charged polymers onto the surface to form a polyelectrolyte film of an interpenetrating network of net positively charged polymers and net negatively charged polymers on the surface of the article.

Abstract: A method is described for producing an osmotically compacted polyelectrolyte complex having a first region and a second region, the first region having a greater modulus than the second region. The method comprises contacting an article comprising polyelectrolyte complex to a solution comprising a preferred osmolyte of concentration sufficient to compact said polyelectrolyte complex and terminating the compaction process before the entire article is osmotically compacted. A method is also described for producing a article comprising water and an intermolecular blend of at least one positively charged polyelectrolyte polymer and at least one negatively charged polymer, said article having a core region and a surface region, the surface region having at least twice the elastic modulus of the core region, the method comprising contacting a starting article comprising a blend of said polymers with a solution of osmolyte, wherein the osmolyte is excluded from said article.

Abstract: A fuel cell comprising a proton transporting membrane is provided. The proton transporting membrane comprises a polyelectrolyte film comprising a multilayer comprising an interpenetrating network of a net positively charged polyelectrolyte polymer comprising repeat units with at least two fluorine atoms and a net negatively charged polyelectrolyte polymer comprising repeat units with at least two fluorine atoms, and further comprising a fluorinated counterion within the multilayer.

Abstract: A fuel cell comprising a proton transporting membrane is provided. The proton transporting membrane comprises a polyelectrolyte film comprising a multilayer comprising an interpenetrating network of a net positively charged polyelectrolyte polymer comprising repeat units with at least two fluorine atoms and a net negatively charged polyelectrolyte polymer comprising repeat units with at least two fluorine atoms, and further comprising a fluorinated counterion within the multilayer.

Abstract: A microfluidic device for carrying a liquid, the device comprising a microfluidic channel having an interior wall and a polyelectrolyte film on the interior wall whereby liquid carried by the channel contacts the polyelectrolyte film, the polyelectrolyte film having a thickness of about 1 to about 1000 nanometers and comprising an interpenetrating network of a predominantly positively charged polymer and a predominantly negatively charged polymer, the predominantly positively charged polymer, the predominantly negatively charged polymer or both containing (i) a pH insensitive positively or negatively charged repeat unit having a pKa greater than 9 or less than 3, and (ii) a pH sensitive repeat unit, the pH sensitive repeat unit having a pKa of 3 to 9, whereby the pH of liquid in the microfluidic channel may be used to control the velocity or direction of electroosmotic flow of the liquid within said microfluidic channel.

Abstract: A polyelectrolyte film is provided, the polyelectrolyte film comprises an interpenetrating network of a net positively charged polymer and a net negatively charged polymer, wherein the net positively charged polymer, the net negatively charged polymer, or both contain polymer repeat units with at least two fluorine atoms.

Abstract: A method is described for producing an osmotically compacted polyelectrolyte complex having a first region and a second region, the first region having a greater modulus than the second region. The method comprises contacting an article comprising polyelectrolyte complex to a solution comprising a preferred osmolyte of concentration sufficient to compact said polyelectrolyte complex and terminating the compaction process before the entire article is osmotically compacted. A method is also described for producing a article comprising water and an intermolecular blend of at least one positively charged polyelectrolyte polymer and at least one negatively charged polymer, said article having a core region and a surface region, the surface region having at least twice the elastic modulus of the core region, the method comprising contacting a starting article comprising a blend of said polymers with a solution of osmolyte, wherein the osmolyte is excluded from said article.

Abstract: An article comprising a polyelectrolyte complex, the polyelectrolyte complex comprising an intermolecular blend of a predominantly positively-charged polyelectrolyte and a predominantly negatively charged polyelectrolyte and being free of salt crystals having a size greater than about 1 micrometer and free of voids having a size greater than about 100 nm, the article having no transverse dimension less than about 10,000 nm.

Abstract: A method for causing a membrane to become permeable to a first chemical species, in which the membrane is contacted with a solution comprising a second chemical species. The membrane comprises a polyelectrolyte complex film comprising a positively-charged polyelectrolyte and a negatively-charged polyelectrolyte. The second chemical species selectively interacts with the membrane, and selective interaction of the second chemical species with the membrane causes the membrane to become permeable to the first chemical species, thereby causing the first chemical species to permeate the membrane.

Abstract: An apparatus and method for capillary zone electrophoresis includes a polyelectrolyte multilayer positioned in a capillary tube for analytical separations of macromolecules. The capillary comprises a passage defined by passage walls comprising fused silica. The polyelectrolyte multilayer is positioned within the passage adjacent the walls, and comprises an organic polyelectrolyte. The passage may further comprise nonporous silica particles coated with a multilayer including a plurality of polyelectrolyte layers. An apparatus includes a power supply having a positive electrode and a negative electrode for generating an electric field therebetween. The apparatus includes a capillary having a passage formed by passage walls and comprising therein a polyelectrolyte multilayer positioned substantially within the passage.

Abstract: A nanoparticle has at least one dimension less than 500 nm and comprises a silica surface and a plurality of zwitterionic functional groups covalently bound to the silica surface. Such nanoparticles and dispersions contain such nanoparticle are prepared and used for a variety of purposes.