1143 results about "Hydrophilic polymers" patented technology

This invention is directed to advanced hemorrhage control wound dressings, and methods of using and producing same. The subject wound dressing is constructed from a non-mammalian material for control of severe bleeding. The wound dressing for controlling severe bleeding is formed of a biomaterial comprising chitosan, a hydrophilic polymer, a polyacrylic polymer or a combination thereof. The kind of severe, life-threatening bleeding contemplated by this invention is typically of the type not capable of being stanched when a conventional gauze wound dressing is applied with conventional pressure to the subject wound. The wound dressing being capable of substantially stanching the flow of the severe life-threatening bleeding from the wound by adhering to the wound site, to seal the wound, to accelerate blood clot formation at the wound site, to reinforce clot formation at the wound site and prevent bleed out from the wound site, and to substantially prohibit the flow of blood out of the wound site.

Hydrogels having improved elasticity and mechanical strength properties are obtained by subjecting a hydrogel formulation containing a strengthening agent to chemical or physical crosslinking conditions subsequent to initial gel formation. Superporous hydrogels having improved elasticity and mechanical strength properties are similarly obtained whenever the hydrogel formulation is provided with a foaming agent. Interpenetrating networks of polymer chains comprised of primary polymer(s) and strengthening polymer(s) are thereby formed. The primary polymer affords capillary-based water sorption properties while the strengthening polymer imparts significantly enhanced mechanical strength and elasticity to the hydrogel or superporous hydrogel. Suitable strengthening agents can be natural or synthetic polymers, polyelectrolytes, or neutral, hydrophilic polymers.

A biosensor comprising an electrically insulating base plate, an electrode system containing a working electrode and a counter electrode disposed on the base plate, and a reagent system comprising at least an oxidoreductase, a hydrophilic polymer and an electron mediator, wherein the reagent system further comprises a substance having a function to convert an organic product generated by direct reaction of a substrate to be measured with the oxidoreductase to another compound.

The invention provide a new class of silicone-containing prepolymers containing dangling hydrophilic polymer chains. This class of silicone-containing prepolymer is capable of being actinically crosslinked to form a silicone hydrogel material with a hydrophilic surface without post curing surface treatment. The present invention is also related to silicone hydrogel contact lenses made from this class of silicone-containing prepolymers and to methods for making the silicone hydrogel contact lenses.

The invention provides multi-arm block copolymers useful as drug delivery vehicles comprising a central core molecule, such as a residue of a polyol, and at least three copolymer arms covalently attached to the central core molecule, each copolymer arm comprising an inner hydrophobic polymer segment covalently attached to the central core molecule and an outer hydrophilic polymer segment covalently attached to the hydrophobic polymer segment, wherein the central core molecule and the hydrophobic polymer segment define a hydrophobic core region. The solubility of hydrophobic biologically active agents can be improved by entrapment within the hydrophobic core region of the block copolymer. The invention further includes pharmaceutical compositions including such block copolymers, methods of making such copolymers and pharmaceutical compositions, and methods of using the block copolymers as drug delivery vehicles.

Compositions are provided comprising a lipophilic active compound, e.g., a human or veterinary drug or a nutraceutical, interwoven with a polymeric matrix formed by two or more polymers, wherein one of the polymers is an amphiphilic polymer and the other polymer is either an amphiphilic polymer with a different hydrophobic-hydrophilic balance or a hydrophilic polymer, and the active lipophilic compound has modified physicochemical properties. The composition forms colloidal nanodispersion upon contact with aqueous media.

Tissue dressing assemblies are formed from hydrophilic polymer sponge structures. The tissue dressing assemblies can be used, e.g., (i) stanch, seal, or stabilize a site of tissue injury, tissue trauma, or tissue access; or (ii) form an anti-microbial barrier; or (iii) form an antiviral patch; or (iv) intervene in a bleeding disorder; or (v) release a therapeutic agent; or (vi) treat a mucosal surface; or (vii) combinations thereof. The tissue dressing structures are made compliant, e.g., by (i) micro-fracturing of a substantial portion of the sponge structure by mechanical manipulation prior to use, or (ii) a surface relief pattern formed on a substantial portion of the sponge structure prior to use, or (iii) a pattern of fluid inlet channels formed in a substantial portion of the sponge structure prior to use, or (iv) the impregnation of a sheet material within the sponge structure.

The present invention provides a method of stimulating a subterranean formation penetrated by a well. The formation has a water-bearing section and a hydrocarbon-bearing section. The method includes the steps of: (a) introducing into the formation an aqueous treatment fluid containing a hydrophobically-modified relative permeability modifier, and (b) introducing an acidizing treatment fluid into the formation. The hydrophobically-modified RPM can be formed and introduced into the formation in several ways. For example, the hydrophobically-modified RPM can be the reaction product of a hydrophilic polymer and a hydrophobic compound that are capable of reacting with each other. The hydrophilic polymer is a polymer containing reactive amino groups in the polymer backbone or as pendant groups, which are capable of reacting with a hydrophobic alkyl halide compound. The hydrophobically-modified RPM can include, for example, a polymer of DMAEMA quaternized with an alkyl halide, wherein the alkyl halide has an alkyl chain length of 6 to 22 carbons.

Improved compositions comprise a polymer and carbon fibers, such as nanotubes. In some embodiments, the carbon fibers, e.g., nanotubes, can be mechanically blended or incorporated into the polymer, while in some embodiments carbon nanotubes also may be covalently bonded to the polymer to form corresponding covalent materials. In particular, the polymer can be covalently bonded to the side walls of the carbon nanotubes to form a composite with particularly desirable mechanical properties. Specifically, the bonding of the polymer to the nanotube sidewall can provide desirable mechanical properties of the composite due to the orientation relative to other types of association between the nanotubes and the polymer. The processing of the nanotubes can be facilitated by the dispersion of the nanotubes in an aqueous solution comprising a hydrophylic polymer, such as ethyl vinyl acetate. A dispersion of nanotubes can be combined with a polymer in an extrusion process to blend the materials under high shear, such as in an extruder. In general, various articles can be formed that take advantage of the properties of the composite materials incorporating a polymer and carbon fibers, such as carbon nanotubes.

This invention includes a wettable biomedical device containing a high molecular weight hydrophilic polymer and a hydroxyl-functionalized silicone-containing monomer.

The present invention provides cationic-polymer-lipid conjugates (CPLs) such as distal cationic-poly(ethylene glycol)-lipid conjugates which can be incorporated into conventional and stealth liposomes or other lipid-based formulation for enhancing cellular uptake. The CPLs of the present invention comprise a lipid moiety; a hydrophilic polymer; and a polycationic moiety. Method of increasing intracellular delivery of nucleic acids are also provided.

A water-based coating composition suitable for preparing hydrophilic surfaces on various articles is provided which includes a supporting polymer having functional moieties capable of undergoing crosslinking reactions, said supporting polymer soluble in or emulsified in an aqueous based medium; and a hydrophilic polymer, said hydrophilic polymer associated with the supporting polymer. The composition is characterized in that, when crosslinked at the functional moieties, the supporting polymer forms a three-dimensional network which substantially minimizes disassociation of the hydrophilic polymer.

The present invention relates to compositions comprising at least one stable, near-monodisperse, non-reactive hydrophilic polymer comprising in said polymer's backbone, a hydrophilic segment having a degree of polymerization of about 10 to about 1000, and a linear silicone segment at least one terminal end of said non-reactive hydrophilic polymer, wherein said silicone segment comprises between about 6 and about 200 siloxy units, and said non-reactive hydrophilic polymer is associated, via the linear silicone block with a silicone hydrogel. The non-reactive hydrophilic polymers may be incorporated into the formulation from which the silicone hydrogel is made or may be contacted with the silicone hydrogel post formation.

The invention provide a class of chain-extended polysiloxane crosslinkers which comprises (1) at least two polysiloxane segments, wherein each pair of adjacent polysiloxane segments is linked by one divalent organic radical which includes at least one pendant hydrophilic group (hydroxyl and/or carboxyl groups) or at least one dangling hydrophilic polymer chain and a di-thioether linkage —S-DR—S— in which DR is a divalent organic radical; and (2) two terminal ethylenically unsaturated groups. The present invention is also related to a polymer comprising crosslinking units derived from chain-extended polysiloxane crosslinker of the invention and to ophthalmic lenses comprising such a polymer.

One aspect of the invention relates to a graft, a surface of which is coated with an amphiphilic block copolymer that includes both hydrophobic and hydrophilic polymer chains. An amphiphilic block copolymer coating according to the invention can serve as a carrier for a very broad range of drugs, possibly including every drug presently used, being considered for use, or likely to be used in the future to inhibit stenosis. The release rates of the drugs can be controlled, for example, through the length of the polymer chains, through their ratio, or through the degree of cross-linking.

A manufacturing method of modified hydrophilic Polyurethane memory foam and products thereof are disclosed. The starting material of the foam includes hydrophilic PU prepolymer, acrylic emulsion polymer and second polyether polyol. The hydrophilic PU prepolymer consists of a first polyether polyol and isocyanate. The molecular weight of the first polyether polyol ranges from 600 to 2000 and the first polyether polyol contains at least 40 mole % of -EO— where the content of the -EO— ranges from 20 to 99.9 wt %. The foaming agent is carbon dioxide produced by the reaction of isocyanate and the water. After foaming process, there is a heating step for dehydration. The foam has specific high hydrophilic polymer structure with features of shock absorbing, uniform pressure relief, moisture absorbency and heat absorbing so as to provide users dry and cool feelings. It wouldn't become rigid below 10 degrees Celsius.

Molecular adsorption to the microfluidic device surfaces can be passively and actively mitigated by mixing certain hydrophilic polymers (organic polymers with repeating hydrophilic groups—the preferred polymers being amphipathic surfactants—with the sample liquid during or prior to relevant microfluidic operations. Nonionic surfactants such as polyoxyethylene sorbitan monooleate and polyoxyethylene octyl phenyl ether are especially effective. High molecular weight polyethylene polymers are also effective. The hydrophilic polymers appear to prevent binding of the fouling molecules to the microfluidic by occupying the surface sites in place of the fouling molecules or by interacting with the fouling molecules to prevent binding of the fouling molecules the surface. When surface adsorption is thus mitigated, microfluidic devices can readily handle samples containing biomolecules to enable active sample concentration, filtering, washing, transport, mixing and other sample handling operations.