Abstract:
The present invention relates to a composite sponge wound dressing and method for producing the same. Chitosan and &bgr;-Chitin is mixed in a specific ratio for forming the sponge for wound repairing. Particularly, when said ratio is between 0.1˜1, the composite sponge wound dressing has a better absorption and tensile strength.
Abstract:
A process of fabricating a porous silicone product utilizing a silicone emulsion capable of forming an elastomer by removal of water therefrom. The silicone emulsion comprises a water emulsion of an organopolysiloxane, a cross-linking agent, and a curing catalyst. The process comprises the steps of freezing the silicone emulsion, and drying the frozen silicone emulsion, whereby water is sublimed therefrom and the porous silicone product is obtained. The resulting porous silicone product is best utilized as a selective permeable membrane for separation of a liquid component from a liquid solution containing two or more liquid components.
Abstract:
A multi-cellular cellulose particle having a multiplicity of cells spaced from one another by cell membranes is described, which cells have a maximum inscribed sphere diameter of larger than 2 .mu.m. The cells have a continuous hole structure in which the cells communicate with one another through openings in the membranes separating two adjacent cells. The multi-cellular cellulose particle is prepared by forming drops of a solution of cellulose or a cellulose derivative, cooling the drops at a temperature lower than the solidification temperature of the solution to freeze the drops, and removing the solvent by extraction or nullifying the dissolving power of the solvent.
Abstract:
The invention relates to polyolefin foams consisting of polyolefins of ultrahigh molecular weight, i.e. weight-average molecular weight from about 4.times.10.sup.5 to 6.times.10.sup.6 g/mol and higher, and to a novel process for producing these foams by foaming a solution of a polyolefin of ultrahigh molecular weight in a solvent with the use of a physical or chemical blowing agent or of an inert gas blown into the solution, and cooling of the resulting foam to a temperature below the gelling temperature of the polyolefin. If appropriate, these foams can be provided wholly or partially with a smooth skin on their surface by superficial cooling, if appropriate under the action of pressure. These foams are distinguished by high tensile strength and impact strength values, shock-absorbing properties, low glass transition temperatures, low embrittlement at low temperatures and high chemical resistance, and they are used especially as mechanical and acoustic insulating materials, materials of construction, filter agents and implantation materials.
Abstract:
Disclosed are an aerogel with a hierarchical pore structure formed using a pulsed laser technology, and a preparation method and use thereof. In the preparation method, a nano silicon-containing inorganic material as a freezing element, a biomass polymer as a cross-linking agent, and deionized water as a solvent are mixed and a resulting mixture is left to stand and gelatinized to obtain a hydrogel; the hydrogel is frozen to form ice crystals therein, and the ice crystals are removed by freeze-drying to obtain a micron-nano porous aerogel; the micron-nano porous aerogel is subjected to customized millimeter-scale punching using a pulsed laser to obtain an aerogel with a millimeter-micron-nano hierarchical pore structure.
Abstract:
The present invention relates to a method of forming a foam material, the method comprising the steps of: a) providing an aqueous dispersion comprising polymer particles and a functional filler dispersed in the aqueous phase, and b) lyophilising the aqueous dispersion, to thereby form the foam material. The invention also relates to a foam material produced by the method, and uses of the foam material, for example in anti-static casings, electrode materials, support elements, insulators, catalysis, as membranes for water filtration, implantable materials for biomedical engineering and electromagnetic interference shielding.
Abstract:
An anti-biofouling shape-memory composite aerogel includes a unidirectional chitosan aerogel channel, a plant polyphenol coating, and a polyphenol/iron ion chelate. The plant polyphenol coating is evenly distributed on an inner wall of the unidirectional chitosan aerogel channel, and the polyphenol/iron ion chelate is located at a top end of the unidirectional chitosan aerogel channel. The anti-biofouling chitosan-based composite aerogel has an evaporation rate of 1.96 kg·m−2·h−1 at an illumination intensity of 1 kW/m2. The composite aerogel has shape-memory properties, and can quickly restore its original shape in water after extrusion, thereby accelerating the diffusion of substances to complete the modification of inner channels. In this way, desirable anti-biofouling ability is achieved, and excellent structural stability as well as continuous and efficient photothermal water evaporation are guaranteed in a complex water environment.
Abstract:
Mechanically strong, biodegradable and reusable aerogels are disclosed, which can be made with a cross-linked cellulose ester, and which exhibit a low density and high porosity. The aerogels disclosed herein may be used as sorbent materials and can be modified with a hydrophobic and/or oleophilic agent.
Abstract:
This disclosure provides systems, methods, and apparatus related to thermoelectric polymer aerogels. In one aspect, a method includes depositing a solution on a substrate. The solution comprises a thermoelectric polymer. Solvent of the solution is removed to form a layer of the thermoelectric polymer. The layer is placed in a polar solvent to form a gel comprising the thermoelectric polymer. The gel is cooled to freeze the polar solvent. The gel is placed in a vacuum environment to sublimate the polar solvent from the gel to form an aerogel comprising the thermoelectric polymer.