541 results about "Polyurethane elastomer" patented technology

The present invention relates to the field of polyurethane materials and particularly to a temperature-induced color-changing vehicle film and a preparation method therefor. The method of the present invention comprises: firstly, using polyurethane to wrap vanadium dioxide powder to obtain color-changing microcapsules; then using 1,1,1,3,5,5,5-heptamethyltrisiloxane and 3-allyloxy-1,2-propanediol as raw materials to synthesize an organosilicon-modified diol, and enabling trimellitic anhydride to react with toluene diisocyanate to synthesize a dicarboximide compound; enabling the organosilicon-modified diol and the dicarboximide compound to undergo an esterification reaction and a polymerization reaction to obtain an organosilicon-modified imide polyester diol; then mixing the organosilicon-modified imide polyester diol with polytetrahydrofuran ether glycol 2000, and then enabling the mixture to react with toluene diisocyanate to obtain a polyurethane elastomer; and mixing the polyurethane elastomer, the color-changing microcapsules, a silane coupling agent, a plasticizer, an antioxidant, and an ultraviolet light absorber, followed by melt extrusion and blow molding into a film, so as to obtain the temperature-induced color-changing vehicle film.

The invention relates to the field of drag chain cables, in particular to a high-flexibility shielding type drag chain cable and a preparation method thereof. The drag chain cable sequentially comprises a conductor layer, a shielding layer and a sheath layer from inside to outside. The conductor layer is formed by compositely twisting silver-plated copper wires and carbon fibers; the shielding layer comprises an inner shielding layer and an outer shielding layer, the inner shielding layer is wrapped by an aluminum-plastic composite belt, and the outer shielding layer is a tinned copper wire woven mesh. The sheath layer comprises the following components: a modified polyurethane elastomer, an ethylene-vinyl acetate copolymer, nitrile rubber, a composite flame retardant, a plasticizer, an antioxidant, a light stabilizer and a lubricant. Through the structural design of the conductor layer, the shielding layer and the sheath layer and the optimization of the material formula of the sheath layer, the problems that an existing drag chain cable is insufficient in strength and flexibility, limited in shielding effectiveness, poor in wear resistance and weather resistance and difficult to consider both flame retardance and mechanical property are solved.

The invention provides a carbon dioxide based polycarbonate-polyester-polyether block copolymerized diol, a star-shaped carbon dioxide based polycarbonate-polyester-polyether copolymerized polyol, and a star-shaped carbon dioxide based polycarbonate-polyester-polyether copolymerized polyol with a low molecular weight. By adjusting the specific polyether content, chain segment distribution and molecular weight, the three polyols can be used for preparing polyurethane elastomers, soft foam and hard foam respectively. The low-temperature brittleness of the polyurethane material is improved while the elasticity of the polyurethane material is improved.

The invention discloses a preparation method and application of a reproducible self-healing polyurethane elastomer with synergism of dynamic silicon oxygen bonds and multiple hydrogen bonds. The method comprises the following steps: (1) carrying out a pre-polymerization chain extension reaction on polytetrahydrofuran, isophorone diisocyanate and a catalyst; (2) adding a 3, 13-dihydroxy propyl octaphenyl double-layer silsesquioxane monomer to carry out a chain extension reaction, and then adding carbohydrazide to carry out a reaction; and (3) adding glycerol and camphorsulfonic acid, uniformly stirring, pouring into a mold, curing and drying, thereby obtaining the reproducible self-healing polyurethane elastomer with synergistic dynamic silicon-oxygen bonds and multiple hydrogen bonds. According to the invention, a common fabric is soaked in a dispersion liquid formed by uniformly mixing diluted polyurethane and hydrophobically modified MXene to obtain the multifunctional composite material with the functions of self-cleaning, self-repairing, photo-thermal conversion and human body sensing.

The invention relates to the field of high polymer material processing, in particular to an in-situ elastomer fiber toughened polylactic acid composite material and a preparation method thereof. The in-situ elastomer fiber toughened polylactic acid composite material provided by the invention comprises a polylactic acid matrix and elastomer fibers dispersed in the polylactic acid matrix, and the elastomer fibers are formed in the polylactic acid matrix in situ by a fiber forming phase; the fiber forming phase is a polyolefin elastomer, a polyurethane elastomer or a styrene elastomer; the polylactic acid matrix is formed by polylactic acid, and the mass ratio of the polylactic acid to the fiber forming phase is (80-100): (1-20). The elastomer added in the in-situ elastomer fiber toughened polylactic acid composite material prepared by the invention forms fibers in situ, so that the stress of a crack propagation tip is effectively absorbed, and the toughness of polylactic acid can be effectively improved under the condition of maintaining the strength and modulus of polylactic acid.

The invention discloses polycaprolactone dihydric alcohol containing maleimide groups and a preparation method and application thereof, and the preparation method of the polycaprolactone dihydric alcohol comprises the following steps: adding N-(2, 3-dihydroxy propyl) maleimide, caprolactone and a catalyst into a reaction container, carrying out high-temperature reaction for 12-18 hours, filtering, washing, and drying to obtain the polycaprolactone dihydric alcohol containing the maleimide groups. And cooling and discharging to obtain the polycaprolactone diol containing the maleimide group. The polycaprolactone diol containing the maleimide group is used as a raw material to prepare a polyurethane prepolymer, so that the side chain of the prepolymer is provided with the maleimide group, and then a difuran compound is introduced as a dynamic cross-linking agent to obtain the self-repairing polyurethane elastomer containing the Diels-Alder bond. Through the reversible Diels-Alder (D-A) reaction effect of the functional components, the polyurethane elastomer can be remodeled and recycled, and the polyurethane elastomer has excellent and stable mechanical properties, self-repairing efficiency and repeated self-repairing capability.

The invention discloses a wear-resistant stone-impact-resistant powder coating and a preparation method thereof, and belongs to the technical field of paints.The wear-resistant stone-impact-resistant powder coating has the advantages that epoxy resin, a polyurethane prepolymer mixture and a high-temperature-resistant and low-temperature-resistant elastomer modifier are compounded to form an epoxy-polyurethane-elastomer chemical bonding effect, and the wear-resistant stone-impact-resistant powder coating is excellent in compatibility and better in crosslinking density, flexibility and elasticity; the stone impact resistance is greater than or equal to 4B grade, and the problem of poor stone impact resistance of a powder coating in the prior art is effectively solved; the epoxy resin is compounded by bisphenol A epoxy resin and hydrogenated bisphenol A epoxy resin, and forms a coating system with a composite antirust system, a gradient wear-resistant filler (compounded by nano ZrO and emery powder), a composite antirust system and a composite flame retardant, and interacts with each other, so that the wear resistance, the impact resistance, the flame retardance and the corrosion resistance of the coating are further enhanced, and the service life of the coating is prolonged. And the coating is durable, so that the frequent maintenance or replacement requirement of the chassis is reduced, and the coating is also suitable for protecting high-value parts of the new energy automobile.

The invention discloses a compression-resistant and wear-resistant cable and a preparation method thereof, the compression-resistant and wear-resistant cable comprises a cable core, a wrapping layer and a sheath layer, the cable core is formed by twisting a plurality of wire cores, each wire core is composed of a conductor formed by twisting a plurality of tinned copper wires and an insulating layer wrapping the conductor, and fillers are arranged between the wire cores and the wrapping layer; the outer sheath layer is prepared from the following components in parts by weight: 100 parts of a polyurethane elastomer, 10-15 parts of a modified filler, 1-2 parts of a lubricant, 0.5-0.7 part of an antioxidant and 0.3-0.5 part of an ultraviolet light absorber. According to the pressure-resistant and wear-resistant cable, the modified filler prepared by a specific method is added into the outer sheath layer, and the interface bonding strength of the filler and a polyurethane matrix is greatly enhanced, so that the cable sheath layer is endowed with excellent tear strength, compression resistance and wear resistance, and the service life of the cable in a harsh industrial environment is remarkably prolonged.

The invention discloses a soft and light cable for ocean engineering, and belongs to the technical field of ocean engineering, a sheath adopts a double-layer polyurethane structure, modified aramid fibers are embedded between inner and outer layers of polyurethane to serve as a reinforcing layer, and the modified aramid fibers are formed by generating oxygen-containing polar groups on the surfaces of the aramid fibers through surface modification. The modified aramid fiber and the polyurethane form chemical bonding in the processing process, and the sheath is made of thermoplastic polyether polyurethane elastomer; the interface bonding strength between the sheath material and the modified aramid fiber woven material is high, different use environments can be better adapted, the inner and outer sheath structures are not easy to move, and the inner material is better protected. The sheath is made of polyurethane, and the polyurethane has high tensile strength, wear resistance and tear resistance and can bear mechanical stress and impact in the marine environment.

The invention belongs to the technical field of new energy materials, and particularly relates to a solid electrolyte material for a lithium battery and a preparation method thereof. The solid electrolyte material for the lithium battery is a polyurethane elastomer and consists of a polyether ion conduction soft segment and an isocyanate crosslinking hard segment, the soft segment is selected from polyether polyol and accounts for 66-90% of the total mass of the polyurethane elastomer; the hard segment is formed by reacting diisocyanate with a chain extender, and accounts for 10-34% of the total mass of the polyurethane elastomer; and the ether solvent is sealed in the soft segment phase by the polymer network. The polyurethane elastomer disclosed by the invention has high ionic conductivity, excellent mechanical property and good interface compatibility, and can be suitable for different types of lithium batteries, such as lithium ion batteries, lithium metal batteries, high-voltage lithium ion batteries and the like; and the preparation process is simple and suitable for large-scale industrial production.

The invention discloses a double dynamic bond self-repairing polyurethane elastomer as well as a preparation method and application thereof, and belongs to the technical field of high polymer materials. The elastomer is prepared from the following raw materials in percentage by mass: 74 to 76 percent of polyether polyol, 15.5 to 18 percent of diisocyanate, 1.67 to 7 percent of dihydrazide compound and 2.1 to 6.7 percent of disulfide. The preparation method comprises the following steps: firstly, reacting polyether polyol with diisocyanate to obtain a prepolymer, then sequentially carrying out step-by-step chain extension reaction on the prepolymer, the bishydrazide compound and the disulfide compound, and finally, curing and forming. According to the invention, a synergistic structure of a hydrogen bond hard segment and a disulfide bond soft segment is constructed step by step, so that the material has high mechanical properties and efficient self-repairing capability. The elastomer is suitable for the fields of industrial pipeline sealing pieces, flexible packaging films, sports equipment accessories and the like, and solves the problem that the strength and repairing performance of an existing self-repairing polyurethane material are difficult to balance.

Disclosed in the present invention are a heat-insulating polyurethane multilayer film and a preparation method therefor. The preparation method comprises the following steps: uniformly mixing a polyester polyol and a polylactic acid polyol, then adding polyisocyanate, and heating and stirring the mixture to react to obtain a precursor; adding a chain extender and stirring the mixture to react to obtain a polyurethane elastomer solution; coating a PET release film with the polyurethane elastomer solution, and drying to obtain a first TPU base film and a second TPU base film; coating a surface of the first TPU base film with a coating layer containing a heat-insulating nanomaterial and then covering with the second TPU base film, followed by curing; forming a heat-insulating layer in the middle layer between the two base films; and peeling off the release film from the second TPU base film, coating the second TPU base film with a self-repairing protective coating layer, peeling off the release film from the first TPU base film, and coating a back surface of the first TPU base film with a pressure-sensitive adhesive layer, followed by baking and drying. The multilayer composite film obtained by the present invention has high transparency, and a good self-repairing function is realized by utilizing a polyurethane elastomer.

The invention discloses a liquid metal acoustic sensing fiber and a preparation method thereof.The sensing fiber is of a skin-core structure and comprises a skin layer and a core layer, the skin layer comprises a polyurethane elastomer, and the core layer comprises a conductive composite layer composed of liquid metal, nano-silver, carbon nanotubes and the polyurethane elastomer; wherein the conductive particles are liquid metal, nano silver and carbon nanotubes. The skin-core structure acoustic sensing fiber is prepared through the liquid metal, nano-silver and carbon nanotube composite conductive material and a coaxial wet spinning process, the skin-core structure acoustic sensing fiber is excellent in conductivity, stretchable, good in acoustic response performance and sensitive to sound waves of different frequencies, the preparation process is simple, large-scale production is easy, the cost is low, and the material is resistant to electromagnetic interference and high in environmental adaptability.

The invention discloses a high-resilience anti-fouling sponge material and a preparation method thereof, belongs to the technical field of preparation of anti-fouling sponges, and aims to solve the technical problem that the resilience and thermal aging resistance of anti-fouling sponges in the prior art need to be further improved. The preparation method specifically comprises the following steps: mixing polyethylene glycol, modified polysilanediol, flexible aerogel, a polyurethane foam stabilizer, deionized water and stannous octoate to obtain mixed alcohol; modified polysilanediol and flexible aerogel are introduced to construct a multi-scale collaborative network, the integrated design of structure enhancement and body pollution resistance of the polyurethane elastomer is achieved, and different from a traditional surface coating means, according to the scheme, pollution resistance and mechanical properties are embedded in a material system, so that the structural enhancement and body pollution resistance of the polyurethane elastomer are improved, and the structural enhancement and body pollution resistance of the polyurethane elastomer are improved. Long-term stability and complex working condition adaptability are both considered, and the flexible aerogel and the organic framework form a uniformly dispersed structure, and meanwhile, the framework is supported to improve toughness and rebound resilience.

The invention belongs to the technical field of polyurethane elastomers, and particularly relates to a high-adhesion and high-moisture-permeability polyurethane microporous elastomer as well as a preparation method and application thereof. Comprising a component A and a component B, wherein the component A comprises 55-80 parts of polyester polyol P1; 20 to 45 parts of polyester polymer polyol P2; 5 to 10 parts of silane modified polyether polyol S1; 3 to 10 parts of a chain extender; 1-2 parts of a cross-linking agent; 0.3 to 0.6 part of a foam stabilizer; 0.5 to 0.8 part of a foaming agent; 1-2 parts of a catalyst; the component B comprises the following components in parts by weight: 10-20 parts of polyester polyol P1; 2 to 10 parts of silane modified polyether polyol S1; and 70 to 88 parts of isocyanate. The prepared polyurethane microporous elastomer not only has excellent bonding strength and stable processability (no bubble is generated), but also has remarkably improved moisture permeability, comfort, high elasticity and folding resistance when being used as a sole material.

The invention relates to a polyurethane-based composite solid polymer electrolyte film and a preparation method and application thereof, and belongs to the field of organic polymer solid electrolyte preparation. Polyethylene glycol-polypropylene glycol triblock copolymer and hydroxyl-terminated polybutadiene are used as soft segments, isophorone diisocyanate is used as a hard segment, and under the action of a catalyst, the polyurethane-based composite solid polymer electrolyte film is prepared. A chain extender containing disulfide bonds is utilized, and a polyurethane elastomer is prepared through gradual addition polymerization reaction; a polyurethane elastomer and a mixed solution of a lithium salt and a polyvinylidene fluoride-hexafluoropropylene copolymer are uniformly mixed, the polyurethane elastomer accounts for 10%-30% of the mass of the polyvinylidene fluoride-hexafluoropropylene copolymer, a precursor solution is obtained, the precursor solution is prepared into a film, and the polyurethane-based composite solid polymer electrolyte film is obtained. The polymer solid electrolyte membrane with excellent mechanical property and excellent lithium ion conductivity is constructed, and the development requirement of a high-performance lithium metal battery is met.

The invention discloses a method for preparing a high-impact-resistance cosmetic bottle material through PET regeneration, belongs to the technical field of PET regeneration and utilization, and aims at solving the technical problem that in the prior art, when PET is regenerated for preparing an impact-resistance cosmetic material, the mechanical property and the transparency of the material need to be further improved. Comprising the following steps: crushing waste PET into PET powder with the particle size of 2-5mm, and then performing alcoholysis regeneration on the PET powder to obtain BHET. According to the invention, the waste PET is taken as a raw material, the regenerated PET with reaction activity is obtained through depolymerization, amination and repolymerization, and the regenerated PET is reinforced through the polyurethane elastomer and the activated silicon dioxide, so that the bending stress and the impact resistance of the cosmetic bottle material are effectively improved, and the transparency of the cosmetic bottle material is also improved; the high-valued application of the waste PET regenerated material in the field of high-end cosmetic packaging is realized.

The invention discloses a large-current-carrying-capacity copper core conductor flexible fire-resistant low-voltage cable, belongs to the technical field of flexible fire-resistant cables, is used for solving the technical problem that in the prior art, the current-carrying capacity, the flexibility, the mechanical property and the flame-retardant and fire-resistant performance of a flexible fire-resistant low-voltage cable need to be further improved, and specifically comprises a copper core conductor, a fire-resistant layer and an insulating layer, the insulating layer comprises the following components in parts by weight: 60-70 parts of silicone rubber, 40-50 parts of a polyurethane elastomer, 3-5 parts of an additive and 0.8-1.2 parts of a vulcanizing agent. According to the low-voltage cable, a polyurethane / silicone rubber composite system with the synergistic effect of the surface modified inorganic filler and the modified polysiloxane is coated outside a conductor structure wrapped by the folded slotted copper bars and the mica tape, and the low-voltage cable with large current-carrying capacity, excellent flexibility, relatively high mechanical property and flame-retardant and fire-resistant performance is prepared.

The application provides a light EVA composite chemical foaming sole material with a bimodal cell structure and a preparation method thereof, and the method comprises the following steps: S1, 50-70 parts of ethylene-vinyl acetate, 10-25 parts of polyolefin thermoplastic elastomer, 20-40 parts of low-molecular-weight thermoplastic elastomer, wear-resistant agent and active agent are mixed, melt homogenization granulation is carried out, and a first material is obtained; the low-molecular-weight thermoplastic elastomer is selected from one or more of polyurethane elastomer, polyester elastomer and polyamide elastomer; S2, the first material, a chemical foaming agent and a crosslinking agent are mixed and then granulated to obtain a second material; S3, the second material is subjected to injection pressure holding and temperature reduction foaming; and S4, the small foaming semi-finished product obtained is subjected to secondary mold pressing to obtain the light EVA composite chemical foaming sole material. The foaming sole prepared by the application has the characteristics of low specific gravity, high resilience and small shrinkage, the physical properties are controllable, and the market prospect is good.

The invention discloses a design method of an anti-corrosion and wear-resistant reinforced sucker rod, and relates to the technical field of oil exploitation equipment. According to the method, chemical components of the sucker rod are optimized, alloy elements such as chromium, nickel and molybdenum and microalloy elements such as niobium, titanium and vanadium are added, meanwhile, the surface treatment processes of boriding, nickel-phosphorus alloy plating and polyurethane elastomer coating are adopted, all links of the manufacturing process are optimized, and the manufacturing process is optimized. The corrosion resistance, the wear resistance and the comprehensive mechanical property of the sucker rod are obviously improved. Tests prove that the sucker rod adopting the design method can effectively deal with a complex and severe underground environment, the service life is prolonged, the oil extraction operation cost of an oil field is reduced, and the sucker rod has a wide application prospect.

The invention belongs to the technical field of polyurethane elastomers, and particularly relates to a modified polyester polyol, an antibacterial polyurethane microporous elastomer and a preparation method of the elastomer. The modified polyester polyol is prepared by adopting graft modification Ag (at) SiO2, and the antibacterial polyurethane microporous elastomer is prepared from the modified polyester polyol. The antibacterial polyurethane microporous elastomer is mainly prepared by mixing and curing a component A and a component B, the component A mainly comprises conventional polyester polyol and modified polyester polyol, and the component B mainly comprises conventional polyester polyol, polyether polyol and isocyanate; according to the antibacterial polyurethane microporous elastomer and the preparation method thereof provided by the invention, the prepared polyurethane microporous elastomer is long-acting and stable in antibacterial performance and uniform in dispersion, and keeps excellent physical and mechanical properties and a microporous structure at the same time.

The waveguide polyurethane laminated shock insulation support comprises an upper connecting plate, a lower connecting plate and a shock absorption body arranged between the upper connecting plate and the lower connecting plate, the upper end face of the shock absorption body is fixed to the bottom face of the upper connecting plate through an upper pressure-bearing wear-resisting layer, and the lower end face of the shock absorption body is fixed to the upper end face of the lower connecting plate through a lower pressure-bearing wear-resisting layer; the damping main body comprises a plurality of multi-layer corrugated steel plates which are distributed up and down and polyurethane elastomers which wrap the multi-layer corrugated steel plates and are alternately vulcanized and tightly attached into a whole. The internal structure of the shock insulation support is optimized, energy is absorbed through waveform deformation during shear deformation, transverse expansion deformation of the polyurethane elastomer is limited under vertical load, the contact area with the polyurethane elastomer is increased, friction force is increased, the energy dissipation capacity is enhanced, and the service life of the shock insulation support is prolonged. The problem that a steel plate and polyurethane are separated or relatively slide due to insufficient binding force of a traditional shock insulation support is solved, the interlayer peeling strength is improved, and the vertical bearing capacity of the support is improved.

The invention relates to a carding spunlace non-woven fabric of a composite elastomer and a preparation method thereof, the carding spunlace non-woven fabric of the composite elastomer is prepared from the elastomer and inelastic fiber by adopting a carding web-forming composite spunlace entanglement process, the elastomer is one or a combination of a polyolefin elastomer, a polyurethane elastomer and a spandex elastomer, and the inelastic fiber is one or a combination of the polyolefin elastomer, the polyurethane elastomer and the spandex elastomer. The non-elastic fibers are one or a combination of cellulosic fibers, polyester fibers and polypropylene fibers, and are arranged into a three-dimensional net structure in a carding net forming manner, so that the prepared carding spunlace non-woven fabric has transverse elasticity. According to the product prepared by the invention, the elastomer is used as a skeleton structure and is compounded with inelastic fibers such as the cellulosic fibers, the polyester fibers and the polypropylene fibers, so that the transverse tensile elasticity of the material is realized while better hygroscopicity, air permeability and softness are maintained.

The invention discloses a 3D printing polyurethane elastomer as well as a preparation method and application thereof, and relates to the technical field of high polymer materials. The polyurethane elastomer is composed of a prepolymer containing a dynamic hydrazide urea bond and a hindered urea bond and a monomer containing primary amine, the prepolymer takes polyether polyol and diisocyanate as basic raw materials, a dynamic hydrazide urea bond hard segment is introduced into the prepolymer through a hydrazide chain extender, a side chain is introduced through glycidyl methacrylate, and the primary amine-containing monomer is prepared. A dynamic hindered urea bond and a photocuring group are introduced through an acrylate end-capping reagent, and a reactive diluent and a photoinitiator are matched to optimize the forming performance. In the preparation process, a prepolymer and a primary amine-containing monomer are mixed and then subjected to 3D printing forming, in the low-temperature stage, reversible exchange of dynamic hydrazide urea bonds and hindered urea bonds is promoted to heal interlayer defects, and in the high-temperature stage, the hindered urea bonds are triggered to break and react with primary amine to form a stable cross-linked network. The 3D printing polyurethane elastomer has excellent rebound resilience, mechanical strength and hydrophobic effect.

A protective layer forming device includes lubricant including fatty acid metal salt and a lubricant application blade. The lubricant application blade includes a contact portion contacting a surface of an image bearer to apply the lubricant on the surface of the image bearer. The contact portion includes polyurethane elastomer that includes a reaction product of polytetramethylene ether glycol, aromatic isocyanate, and amine. The contact portion has a Martens hardness of 5.0 N / mm2 or more and 30.0 N / mm2 or less. The lubricant applied to the surface of the image bearer by the lubricant application blade has a normalized ionic strength A of a metal ion amount derived from the fatty acid metal salt, satisfying a following expression (1),1⁢E-4<A<20⁢E-4,(1)where the normalized ionic strength A is measured by a time-of-flight secondary ion mass spectrometer.

The invention belongs to the technical field of pressure sensors, and relates to a high-resistance pressure-sensitive carbon paste for a thin film type array pressure sensor, and a preparation method and application of the high-resistance pressure-sensitive carbon paste. According to the high-resistance pressure-sensitive carbon paste disclosed by the invention, in the cured carbon paste layer, the carbon powder and the epoxy resin cooperatively construct a stable three-dimensional network structure through the polyurethane elastomer. Wherein the polyurethane endows the material with excellent rebound resilience, so that the material can be quickly recovered after being pressed; the hollow glass beads are uniformly dispersed in the network, so that not only is the supporting capacity of the structure enhanced, but also the effects of stress dispersion and elastic supporting are achieved in the compression process, and rapid separation of carbon powder contact points after pressure relief is promoted; the epoxy resin provides excellent structural stability and adhesive force, prevents aging, cracking or performance degradation of the coating in long-term use, and ensures the durability of the sensor.

This application discloses a diaphragm for a sound-generating device and its preparation method, as well as the sound-generating device itself. The diaphragm comprises at least one microporous polyurethane elastomer film layer, which includes a polyurethane elastomer and a micropore-forming material. The microporous polyurethane elastomer film layer has micropores. The micropore-forming material includes inorganic hollow microspheres, with the content of inorganic hollow microspheres accounting for 5wt% to 50wt% of the total amount of the microporous polyurethane elastomer film layer. The average pore size of the micropores is 1μm to 60μm, and the loss factor of the microporous polyurethane elastomer film layer at room temperature is ≤0.15. The diaphragm of this application, by incorporating inorganic hollow microspheres into the polyurethane elastomer to form a microporous polyurethane elastomer film layer, not only reduces the density of the diaphragm and improves the mid-frequency sensitivity of the sound-generating device, but also, by controlling the amount of inorganic hollow microspheres added, enables the diaphragm material to have suitable damping, balancing the strength and transient resilience required during diaphragm vibration.

The invention discloses a transparent polyurethane elastomer as well as a preparation method and application thereof, and the preparation method comprises the following steps: reacting diisocyanate with polyester polyol under the action of a catalyst to generate an isocyanato-terminated polyurethane prepolymer; and reacting the polyurethane prepolymer with 2, 2 '-dithiobis (acethydrazide) in a first solvent, evaporating the first solvent, and curing to generate the transparent polyurethane elastomer. Through multiple synergistic effects of increasing molecular entanglement, inhibiting hard phase aggregation, promoting supramolecular network crosslinking, a compact hydrogen bond network and a high-hardness hard domain, the polyurethane elastomer has excellent mechanical strength and toughness and has certain self-repairing performance.

Urethane group-containing, isocyanate-terminated prepolymers are made from an organic polyisocyanate and a poly(propylene oxide) that has mainly primary hydroxyl groups and contains 90% by weight or more oxypropylene groups. The prepolymers are useful for making polyurethane elastomers when used in either a one-part, moisture cured process or as a component of a two-part elastomer-forming reactive system. The elastomers tend to have unexpectedly high tensile moduli at a given hard segment content.

The invention discloses a self-repairing anti-twisting shielding composite cable, and relates to the technical field of cables, the self-repairing anti-twisting shielding composite cable comprises a conductor, an insulating layer, a shielding layer and an outer sheath which are sequentially sleeved from inside to outside, and the insulating layer and / or the outer sheath are / is obtained by extruding a self-repairing polyurethane elastomer; the self-repairing polyurethane elastomer is prepared from the following components in parts by weight: 100 parts of soft-segment polyol, 40 to 80 parts of isophorone diisocyanate, 12 to 20 parts of a chain extender containing disulfide bonds and 5 to 12 parts of a chain extender containing ureido, and the soft-segment polyol is selected from at least one of polytetrahydrofuran ether glycol and amino-terminated polydimethylsiloxane. The self-repairing anti-twisting shielding composite cable is high in self-repairing capacity, excellent in anti-twisting performance and stable in shielding performance.