12 results about "Polyvinyl alcohol sponge" patented technology

This invention discloses a polyvinyl alcohol (PVA) sponge material, its preparation method, and its applications. The PVA sponge material is obtained from PVA through ice crystal pore formation and oxidative modification. The PVA sponge material obtained by this invention has a continuous porous structure, and the oxidatively modified PVA sponge possesses aldehyde and carboxyl groups, exhibiting active coagulation function and improving coagulation efficiency. Compared with traditional PVA sponge molding methods, this invention significantly reduces the amount of crosslinking agent aldehyde used, thereby reducing the risk of subsequent biotoxicity. It also avoids biotoxicity caused by incomplete surfactant rinsing and the large amount of wastewater generated during rinsing, which is beneficial for industrial applications.

The invention provides a nitrogen-doped carbon negative electrode material with a three-dimensional conductive network and a preparation method thereof.The preparation method comprises the steps that polyvinyl alcohol sponge adsorbs an aqueous solution containing polyvinylpyrrolidone and liquid asphalt, and after freeze drying, a precursor is obtained; and performing high-temperature carbonization on the precursor to obtain the nitrogen-doped carbon negative electrode material with the three-dimensional conductive network. According to the invention, nitrogen doping is carried out while the hard carbon negative electrode material is prepared, so that the problems of low initial coulombic efficiency caused by surface defects of existing polymer-based hard carbon and difficulty in intercalation of a lithium ion carbon layer of an asphalt-based hard carbon material are solved, and the charge-discharge performance and long-life cycle performance of the asphalt-based hard carbon material when the asphalt-based hard carbon material is used for a lithium ion battery are improved.

The present application relates to a kind of microporous hydrophilic sponge material and the preparation method of the sponge material.The microporous hydrophilic sponge is polyvinyl alcohol sponge, is obtained by the following raw material system reaction, by weight fraction, including each raw material component as follows: first polyvinyl alcohol 100 parts, second polyvinyl alcohol 50-100 parts, deionized water 500-800 parts, formaldehyde aqueous solution 90-150 parts, aliphatic dialdehyde aqueous solution 0.2-0.6 parts, sulfuric acid 30-50 parts;The degree of polymerization of the first polyvinyl alcohol is 1500-2400;The degree of polymerization of second polyvinyl alcohol is 300-700.The microporous hydrophilic sponge material can be used for emulsion separation, average pore size is 5-15 μm, emulsion separation efficiency is greater than 95%;Water flux is greater than 4000 L h ‑1 m ‑2 bar ‑1 .

The invention discloses hydrophilic sponge and a preparation method thereof, and belongs to the technical field of high polymer material preparation. According to the prepared hydrophilic sponge, the high-hydrophilicity polyvinyl alcohol sponge can be obtained based on a room-temperature placing and curing process by utilizing the synergistic effect of the enhancement effect of the nano cellulose and the salting-out effect of the inorganic salt, and the sponge is simple in preparation process, low in cost, free of aldehyde cross-linking agents and acid catalysis and good in biocompatibility. Meanwhile, the sponge has high liquid absorption capacity and rapid expansion performance, and has wide market prospects in the fields of solar steam generation, catalysis, biosensing, water treatment, biomedicine and the like.

The application relates to a polyvinyl alcohol sponge roller for semiconductor cleaning and a preparation method of the sponge roller. The polyvinyl alcohol sponge roller is composed of an inner shaft and a microporous hydrophilic polyvinyl alcohol sponge attached to the outer surface of the inner shaft, and the polyvinyl alcohol sponge is prepared from the following raw material system: 100 parts of first polyvinyl alcohol, 50-100 parts of second polyvinyl alcohol, 500-800 parts of deionized water, 90-150 parts of formaldehyde aqueous solution, 0.2-0.6 parts of aliphatic dialdehyde aqueous solution and 30-50 parts of sulfuric acid, wherein the polymerization degree of the first polyvinyl alcohol is 1500-2400, and the polymerization degree of the second polyvinyl alcohol is 300-700. The polyvinyl alcohol sponge in the sponge roller has a porosity of 80-92%, a pore size of 5-15 mu m, a water absorption rate of more than 400%, and a 30% compression stress of 5-15 KPa under the condition of 200% water content.

The utility model relates to the field of sponge mats, in particular to a long-acting antibacterial and anticorrosive sponge mat. The technical problem to be solved by the utility model is to provide the long-acting antibacterial and anticorrosive sponge mat which can restrain the breeding of microorganisms for a long time, is breathable and deodorant, and keeps the use comfort. A long-acting antibacterial and anticorrosive sponge mat comprises a sponge base body layer and an antibacterial and anticorrosive outer layer wrapping the overall outer surface of the sponge base body layer. The sponge base body layer comprises a first sponge layer and a second sponge layer which are arranged in a stacked mode, and the first sponge layer and the second sponge layer are made of polyurethane sponge or polyvinyl alcohol sponge or natural latex sponge of a porous structure; an antibacterial and anticorrosive inner layer is arranged between the first sponge layer and the second sponge layer, and the surfaces of the two sides of the antibacterial and anticorrosive inner layer are fixedly bonded with the first sponge layer and the second sponge layer. The utility model achieves the effects of inhibiting the breeding of microorganisms for a long time, ventilating and deodorizing, and keeping the use comfort.

The application discloses a hemostatic device applied to various irregular wounds and belongs to the technical field of medical first-aid equipment, which comprises a solid syringe and a medical polyvinyl alcohol sponge strip; the medical polyvinyl alcohol sponge strip can be axially and radially expanded and is punched into a wound by the device, and the sponge strip is used for omnibearing compression hemostasis; meanwhile, the segmented design of the sponge strip allows the selection of a proper number of segments according to the actual length of the wound, so that the wound can be completely covered; after the sponge strip enters the wound, the sponge strip rapidly absorbs blood and expands, generates uniform pressure, effectively seals blood vessels and achieves the purpose of hemostasis; the radial and lateral expansion of the hemostatic sponge strip is realized, the irregular wound is fully covered, the hemostasis effect is remarkably improved, the segmented design makes the hemostatic device capable of flexibly adapting to wounds of different sizes and shapes, the use of additional cutting tools is reduced, the operation process is simplified, the efficient hemostasis mechanism shortens the treatment time, reduces the risk and discomfort of patients and improves the success rate of first aid.

The application discloses a preparation method of polyvinyl alcohol sponge-like gel and belongs to the technical field of high polymer gel preparation. The polyvinyl alcohol solution is obtained by heating and dissolving, then small-molecule polyhydric alcohol, inorganic salt with salt-dissolving effect and inorganic salt with salting-out effect are sequentially added into the polyvinyl alcohol solution, the polyvinyl alcohol composite emulsion is obtained by stirring and mixing, the emulsion is placed and matured at normal temperature to obtain the sponge-like gel with open hole structure, the gel has extremely fast liquid absorption capacity and obvious negative pressure drainage effect, and can be applied to the fields of biological medicine and the like. Meanwhile, the polyvinyl alcohol sponge-like gel can still maintain the shape after repeatedly losing water and rehydrating.

The application relates to the technical field of new materials, in particular to a composite sponge and a feeding assembly in a conveying device thereof. The technical scheme comprises the following steps: a composite sponge is provided, the composite sponge comprises a gel layer and a liquid absorption layer, the number of layers of the gel layer and the liquid absorption layer is multiple, the multiple liquid absorption layers and the multiple gel layers are overlapped, the liquid absorption layer is composed of polyurethane sponge and polyvinyl alcohol sponge in the reticular gap of the polyurethane sponge, the hardness of the composite sponge is greater than 30HD, and the volume of the polyvinyl alcohol sponge accounts for 60-70% of the total volume of the liquid absorption layer. When the polyurethane particle material bounces outwards in the conveying process of the conveying belt, the bounced polyurethane particle material is subjected to the concave arc of the arc-shaped wall flow guide block, the polyurethane particle material slides from the concave arc to the conveying belt after being bounced onto the concave arc, and the arc degrees of the two groups of arc-shaped wall flow guide blocks are greater than each other, so that the collection and blocking ranges of the polyurethane particle material are expanded.

The invention discloses a copper sulfide-loaded interface evaporation composite sponge material and a preparation method thereof, and belongs to the technical field of photothermal conversion materials. The polyvinyl alcohol sponge with good water delivery performance and photo-thermal conversion capability can be obtained by utilizing the synergistic effect of the protection effect of the small organic molecule polyol and the salting-out effect of the inorganic salt and combining with the photo-thermal conversion capability of the copper sulphide, the polyvinyl alcohol sponge is placed and cured at room temperature, the preparation process is simple, the cost is low, and an aldehyde cross-linking agent and acid catalysis are not needed. Meanwhile, the sponge has high liquid absorption capacity and rapid expansion performance, interface evaporation can be efficiently carried out, and the sponge has wide application prospects in the fields of seawater desalination treatment and the like.

The invention relates to polyvinyl alcohol sponge with low formaldehyde content as well as a preparation method and application of the polyvinyl alcohol sponge. Amino and hydroxyl co-grafted hydroxyapatite is added into preparation raw materials of the polyvinyl alcohol sponge. Formaldehyde molecules can be adsorbed to the surface of hydroxyapatite through acting force between amino grafted on the surface of hydroxyapatite and formaldehyde molecules, and primary amine and formaldehyde are converted into relatively stable methylene imine through amination reaction of formaldehyde under a heating condition. Hydroxyl grafted on the surface of hydroxyapatite is easier to participate in cross-linking reaction of polyvinyl alcohol, so that nano-hydroxyapatite can be uniformly and stably dispersed in polyvinyl alcohol sponge, the catalytic performance of nano-sized hydroxyapatite is improved, and loss of hydroxyapatite in the cleaning process can be effectively avoided. The polyvinyl alcohol sponge disclosed by the invention has excellent mechanical properties and relatively low formaldehyde content, and is suitable for preparing a medical nasal cavity filling hemostatic material.

This invention discloses a polyvinyl alcohol (PVA) sponge, its preparation method, and its applications. The PVA sponge comprises a PVA sponge matrix and a layer of polyphenolic compounds on its surface, wherein a polymer with hemostatic properties is grafted onto the surface of the PVA sponge matrix via polyphenolic compounds. This invention utilizes PVA sponge and the biomimetic principle of mussels to construct a secondary reaction platform on the sponge through the strong adhesive effect of polyphenolic compounds. Then, through Schiff base reaction and free radical polymerization, natural polymers with hemostatic properties are grafted onto the sponge, resulting in a PVA hemostatic sponge with excellent hemostatic and mechanical properties for battlefield wound first aid.