Polyvinyl alcohol medical grade microporous sponge is a kind of polymer material with absorbent performance and extremely soft surface when contacting with human body, which can be completely naturally degraded. Its suction performance is not only in the faster suction rate, but also reflected in its super suction ratio. Under normal circumstances, one gram of PAV sponge can absorb more than seven times its own body fluid. Therefore, this kind of material is widely used in modern surgical operation to replace the absorbent cotton and defatted gauze, and is widely used in international clinical surgery. Polyvinyl alcohol medical-grade macroporous sponge suction fluid has performance, high opening rate, high strength, and extremely soft surface when in contact with the human body. It is widely used in clinical trauma surgery, especially in the field of negative pressure drainage. Waste macroporous sponges can be completely naturally degraded and will not cause pollution problems to the environment. In general, one gram of PAV macroporous sponge without excipients can absorb more than nine times its body fluid. This kind of material is used to replace the absorbent cotton and the absorbent gauze in the surgical operation, which can solve the problem that the absorbent cotton or the absorbent gauze needs to be replaced constantly in the clinical operation. Medical polyvinyl alcohol sponge is made of polyvinyl alcohol molecular chain cured by cross-linking agent, without fiber filament or fiber head, and there will be no fiber falling off in use. During eye surgery, ear, nose and throat surgery, brain neurosurgery craniotomy and thoracic surgery heart surgery, it does not affect wound healing due to fiber shedding. According to different clinical uses, if appropriate excipients are loaded into the sponge, it can also promote wound healing. At the same time, the sponge has good mechanical properties and can be processed into various shapes according to different surgical needs. A blood-sucking sponge or sponge rod in the shape of a spear used especially in microsurgery, which can quickly absorb microscopic bleeding and ensure the operation is correct. Fold edit this section method There are mainly physical foaming method, chemical foaming hair and physical and chemical combination of foaming method three methods. But at present, the production technology of PVA sponge absorbent material ly adopts the backward starch filling foaming method. That is, the starch is filled into the PVA solution at the appropriate temperature, and then the starch is washed off after the PVA is cross-linked and solidified at a certain temperature. When this method is used in production, the environment pollution is serious, the follow-up treatment process is long, the starch can not be completely cleaned, and the starch and acid catalyst can not be fully recycled, which is not conducive to saving resources and cutting costs. Fold edit this section production technique There are mainly physical foaming hair, chemical foaming hair and physical and chemical combination of foaming method of three methods. But at present, the production technology of PVA sponge absorbent material ly adopts the backward starch filling foaming method. That is, the starch is filled into the PVA solution at the appropriate temperature, and then the starch is washed off after the PVA is cross-linked and solidified at a certain temperature. When this method is used in production, the environment pollution is serious, the follow-up treatment process is long, the starch can not be completely cleaned, and the starch and acid catalyst can not be fully recycled, which is not conducive to saving resources and cutting costs.

EVA rubber and plastic products are new environmental protection plastic foam materials, with good cushioning, earthquake resistance, heat insulation, moisture-proof, chemical corrosion resistance and other advantages, and do not absorb water. EVA rubber and plastic products can be processed and formed by design. Its shockproof performance is better than that of polystyrene and other traditional foaming materials, and it meets the requirements of environmental protection. It is one of the choices for export products. Thickness: not less than 1mm, not 56mm (whole plate), error range ±0.2mm. Hardness and color: Color EVA commonly used hardness: 38 degrees, black and white color 25 38 45 55 60 70 degrees. Color EVA foam color: gray, yellow, purple, red, blue, coffee, green, orange, etc., environmental protection EVA foam board black, white, color: any color on the international color card can be customized. After cutting edge, high temperature welding can be made into any length of the coil, according to customer requirements can be divided into 0.5mm~50mm thickness can be mounted, composite double-sided tape, width into several strips Features: SHOCkproof: HIGH resilience and tension resistance, strong toughness with shockproof/buffering properties. Environmental protection: EVA raw material itself is environmental protection material, biodegradable. Corrosion resistance: resistant to seawater, grease, acid, alkali and other chemicals corrosion. Heat preservation: EVA has good heat preservation and cold resistance, cold resistance and insolation resistance. No smell: EVA is environmental protection no smell material, suitable for all kinds of products packaging lining. Application: Suitable for electronic products, household appliances, hardware tools, toys, crafts, tourism products, cultural articles, cosmetics, transportation shock absorption and so on

EPE is developable polyethylene, also known as pearl cotton. Non-cross-linked closed-cell structure, it is a high foam polyethylene product produced by extrusion of low density polyethylene (LDPE) as the main raw material, which is composed of numerous independent bubbles produced by physical foaming of low density polyethylene lipid. It overcomes the shortcomings of brittle, deformation and poor recovery of common foam. It is waterproof, shockproof, sound insulation, heat preservation, good plasticity, strong toughness, recycling, environmental protection, strong impact resistance and many other advantages, but also has good chemical resistance. Sponge is ly made of polyisocyanate and polyol as raw materials to synthesize, the basic reaction is the reaction of polyol and polyisocyanate to produce polyurethane, commonly used sponge is called polyurethane soft foam rubber, polyurethane is the common kind of polymer material in life, widely used in the production of various “sponge” products. As well as shock absorbers, anti-friction elastic materials EVA is made of ethylene (E) and ethylene acetate (VA) copolymerization and referred to as EVA. EVA is characterized by good softness, rubber-like elasticity, good flexibility at -50℃, good transparency and surface gloss, good chemical stability, good anti-aging and ozone resistance, and no toxicity. Good mixing with filler, good coloring and forming processing. EVA can be injection molding, extrusion, blow molding, rolling, vacuum thermoforming, foaming, coating, heat sealing, welding and other molding processes, can be used as building materials used as waterproof, fire, sound insulation and other functions of the three differences mainly have the following points: 1 with the naked eye can be distinguished, sponge is generally slightly yellow, very elastic, relatively lighter than these three. EVA is a bit hard, usually black, and is the heaviest among the three. EPE pearl cotton is generally white, which is easy to distinguish from sponge. Sponge can be divided into its original state no matter how you press it, while EPE pearl cotton will hear patter sound when you press it hard, and the place where you press it will be concave. 2.EPE pearl cotton has wavy pattern and looks like it has a lot of foam stuck together. It’s very light.EVA is solid. What’s the partial concentration? It’s heavy.

Some sponges are poisonous. Those that are soft and colourful are likely to be poisonous chemicals. The commonly used sponge is made of foamed plastic polymer, and the recycled sponge is a new type of product, which is mainly formed by crushing, stirring, and high-temperature sterilization of glue steam. Its advantages are good elasticity, good resistance, no odor, and the production cost is lower than that of ordinary sponges. Why do sponges catch fire so badly? Ordinary sponges are actually not very easy to catch fire, and the combustion of sponges requires the presence of heat and oxygen to occur. The sponge will not burn unless it encounters an open flame. For example, an unextinguished cigarette butt falls on the sponge. Under the action of high temperature, the sponge is easily melted, wrapping the cigarette butt, so that the cigarette butt is isolated from the air and extinguished. But the sponge is still very easy to catch fire under the action of an open flame. There are a lot of pores in the sponge. The lower the density of the sponge, the higher the porosity, the lower the ignition point, and the easier it is to catch fire. The pores in the sponge are equivalent to expanding the contact area between the fuel and the air. Therefore, the sponge burns faster and at a higher temperature than ordinary materials. What’s more serious is that after the sponge catches fire, the smoke emitted by the sponge also contains toxic gases. Common sponges in the market include polyurethane type, polyethylene type and polystyrene type. When these types of sponges are burned, they will release toxic gases containing cyanide, carbon or benzene, and the human body will suffocate quickly after excessive inhalation. From the material point of view, the recycled sponge is synthesized from sponge scraps. The properties of the base material are similar to those of ordinary sponges, and the ignition characteristics should be similar.

Latex generally refers to a colloidal emulsion formed by dispersing polymer particles in water. It is customary to refer to the aqueous dispersion of rubber particles as latex; the aqueous dispersion of resin particles is called emulsion. Latex products processed from latex as raw materials, also known as latex products, such as sponges, gloves, toys, hoses, etc., are widely used in daily life. Classification natural latex It flows out from rubber tree tapping (see natural rubber), which is milky white, with a solid content of 30% to 40%, and the average rubber particle size is 1.06μm. Fresh natural latex contains rubber components 27%-41.3% (mass), water 44%-70%, protein 0.2%-4.5%, natural resin 2%-5%, sugar 0.36%-4.2%, ash 0.4% . In order to prevent natural latex from coagulating due to the action of microorganisms and enzymes, ammonia and other stabilizers are often added. In order to facilitate transportation and processing, natural latex is concentrated to a solid content of more than 60% by centrifugation or evaporation, which is called concentrated latex. Natural latex is mainly used in sponge products, extruded products and impregnated products. synthetic latex Generally, synthetic latex (such as polybutadiene latex, styrene-butadiene latex, etc.) with a solid content of 20% to 30% can be obtained by emulsion polymerization. In order to make the solid content reach 40% to 70%, the rubber particles are ly agglomerated into larger particles, that is, in the industry, measures such as adjusting the polymerization formula, adding agglomerating agents, stirring, pressurizing, freezing, etc. Natural rubber latex is concentrated in a similar way. Synthetic latex is mainly used in industrial sectors such as carpet, paper, textile, printing, coatings and adhesives.

Memory foam refers to a polyether polyurethane foam sponge with slow rebound mechanical properties, which is a special sponge developed by a European company. When the flat memory foam surface is pressed by hand, a fingerprint will appear and then slowly disappear. This is the iconic effect of memory foam – “slow rebound”, and it is difficult for other materials to imitate the slow speed of its rebound. The memory foam is soft to the touch. When you hold the memory foam with your hand, you will feel that the palm of your hand is constantly empty, such as an hourglass. When people sit on the memory foam waist pad, they will feel the gradual settling process, like falling into a quagmire, and hear the subtle sound of the continuous flow of gas in the memory foam; when people sit on the memory foam waist pad, they will be deformed continuously at , and then the sense of resistance will disappear. , and the back pain that should have appeared after sitting for a long time, it is hard to find traces. Comprehensive performance (1) It has performance in mechanics such as absorbing impact force, reducing vibration, and releasing low rebound force; it is a buffer material to protect the body of astronauts when the space capsule lands, and it is the material for the packaging of valuable instruments. (2) Provide uniform surface pressure distribution; adapt to the surface shape of external pressure through stress relaxation, so as to reduce the pressure at the point to a , thereby avoiding the parts with microcirculation pressure, and it is a long-term bed rest to effectively prevent bedsores. It can gently maintain the shape of foreign objects and is a good material for posture cushions. (3) Molecular stability, no toxic and side effects in contact with human body, no allergies, no volatile irritating substances, good flame retardant effect and other reliable chemical properties