Preparation method of light / heat curing moldable reactive liquid silicon resin emulsion composition and flexible high-connection-hole foam material

Abstract

The invention discloses a light / heat curing moldable reactive liquid silicon resin emulsion composition which comprises the following components in parts by mass: (A) reactive liquid M and (D) Q silicon resin 100, (B) 50 to 300 parts of water; (C) 0.1 to 12 parts of a nonionic surfactant; (D) 0.5-20 parts of a curing agent; (E) a proper amount of a catalyst; (F) 0-0.5% of an accelerant; and (G) 0-16 parts of nanofibers / particles. The invention further discloses a preparation method of the flexible liquid silicon resin foam material with the high connecting holes. According to the invention, the flexible high-pore-connection liquid silicon resin foam material with any required shape, fine pores, wide density range, high pore connection rate, adjustable hardness, environment friendliness and no pollution can be obtained.

Description

Technical Field

[0001] This invention relates to a liquid organosilicon reactive emulsion and a method for preparing foam materials, particularly to a photo / thermal curable moldable reactive liquid silicone resin emulsion composition and a method for preparing flexible high-pority foam materials, belonging to the technical field of organic foam materials and their preparation. Background Technology

[0002] Liquid silicone foam materials possess excellent flexibility, biocompatibility, and resilience due to their organopolysiloxane backbone. They also exhibit weather resistance, ozone resistance, and heat resistance. Thanks to the low energy consumption and ease of molding of liquid raw materials, products of different densities and shapes can be obtained, meeting the filling, cushioning, vibration isolation, and heat insulation needs of various applications such as medical, clothing, electronics, construction, vehicles, ships, aircraft, and precision instruments.

[0003] While researching liquid silicone rubber foam materials, the inventors discovered that, on the one hand, liquid silicone is limited by its high fluidity, making it difficult to utilize large amounts of high specific surface area (>100m²). 2 The use of nanoparticles (g) for reinforcement generally results in lower mechanical properties; on the other hand, their cell structure and properties are limited by the fluidity of the adhesive and the molding method. For example, the method of using hydroxyl silicone oil as a chemical foaming agent to generate hydrogen gas to form bubbles can only obtain isolated cell structures with large size (>0.3 mm), low mechanical properties, and poor compression recovery, or larger cells and lower density (0.17~0.42 g / cm³). 3 Foam materials with a coarse, continuous cell structure have a low interlocking rate; when using water-soluble solid substances (such as NaCl, NaNO3, etc.) as physical foaming pore-forming agents, the pre- and post-treatment of the pore-forming agent is very cumbersome, the preparation cycle is long, and the applicable density range is narrow (approximately 0.4–0.5 g / cm³). 3 It is difficult to obtain foams with lower or higher densities, and there are problems such as poor resilience, pore-forming agent residue, and environmental pollution from waste liquid. When using the emulsion template method, it is generally only possible to obtain foam materials with small pore size (<20mm) independent cell structure and poor compression recovery, and there are problems such as long molding time and difficulty in drying (requiring high temperature 200℃ long-term treatment). Even the high internal phase emulsion template HIPEs (internal phase >74%) method can only obtain low density (<0.26g / cm³). 3 Low mechanical strength intercellular foam materials, while the method of using anionic or water-soluble, water-absorbing polymers or inorganic green clays to thicken the aqueous phase in the emulsion can improve the cell connectivity, also has the problems of complex process and thickener reducing the heat resistance of foam.

[0004] Therefore, it is evident that liquid silicone rubber itself lacks sufficient strength, and the fluidity requirements limit the amount of reinforcing agent that can be added. When preparing highly interconnected foams, chemical foaming methods are unsuitable (low density, large pore size, low mechanical properties). While the emulsion template method, using high internal phase emulsions (HIPEs) and water for thickening, can produce interconnected foams, it suffers from slow curing speed, poor density adjustability, and the thickener reducing the foam's heat resistance. Furthermore, it cannot simultaneously meet the different crosslinking speed requirements of rapid molding for thin products and slow molding for thick products. To address these issues, the inventors, while researching and applying reactive M(D)Q liquid silicone resin materials, discovered that reactive liquid silicone resin itself possesses high mechanical strength. Using water as the physical foaming component (without special thickening components) and combining it with specific surfactants, it can be dispersed into a two-phase viscous emulsion. After adding curing agents, catalysts, accelerators, etc., and then mixing, dispersing, centrifuging, and molding, it can be cured under light / heat conditions and dried for a short time (1–6 hours) to obtain a foam with micropores and a wide density range (0.3–0.75 g / cm³). 3 This novel high-pority flexible silicone foam material features a high porosity structure (>80%), high mechanical properties, and strong load-bearing capacity. It can achieve rapid UV curing and slow heating curing, offering advantages such as a short process flow, good stability, no waste liquid or other environmental pollutants, and ease of preparation of foams of various sizes and thicknesses. It exhibits good flexibility, excellent resilience, and low compression set, making it particularly suitable for applications such as cushioning, energy absorption, padding, sound absorption, and vibration damping. It can also be used for the separation, recycling, and utilization of valuable waste or environmental pollutants such as waste oil and wastewater, and can be used as a new printing material after absorbing ink. Summary of the Invention

[0005] The purpose of this invention is to provide a photo / thermal curable moldable flexible reactive liquid silicone resin emulsion composition and a method for preparing its foam material, thereby obtaining foam materials with micropores of any desired shape and a wide density range (0.3–0.8 g / cm³). 3 A flexible, highly porous liquid silicone foam material with high interconnectivity (>80%), adjustable hardness, and environmentally friendly and pollution-free properties.

[0006] The present invention is implemented as follows: The inventors, through in-depth research to achieve the above-mentioned objectives, discovered that by combining reactive liquid M(D)Q silicone resin, water, specific nonionic surfactants, curing agents, photothermal catalysts, and nanofibers / particles such as aramid fibers and carbon nanotubes, and dispersing them into a viscous emulsion at room temperature, removing air under (vacuum) centrifugation, and then curing them under ultraviolet light irradiation or at room temperature for an extended period or at a temperature not exceeding 100°C (with pressure), a wide density range (0.3–0.8 g / cm³) can be obtained after drying. 3It is a flexible liquid M(D)Q silicone foam material with high interconnection rate (>80%) and micropores (less than 200 micrometers), adjustable load-bearing capacity, and excellent compression recovery.

[0007] Therefore, the present invention first provides a photo / thermal curable moldable flexible reactive liquid silicone resin emulsion composition, the composition comprising: (A) 100 parts by weight of reactive liquid M(D)Q silicone resin; (B) 50-300 parts by weight of water; (C) 0.1–12 parts by weight of nonionic surfactant; (D) 0.5–20 parts by weight of curing agent; (E) Appropriate amount of catalyst; (F) Accelerator 0-0.5 parts by weight; (G) Nanofibers / particles 0-16 parts by mass.

[0008] The functional groups of the reactive liquid M(D)Q silicone resin in component (A) are selected from at least one of (meth)acrylate, allyl, mercapto(hydrocarbon), vinyl, hydrosilyl, epoxy(hydrocarbon), and amino(hydrocarbon). The HLB value of the nonionic surfactant in component (C) is between 3.0 and 9. Component (G) is selected from at least one of nano-aramid fiber, carbon nanotube, white bleach, hydrophobic silica, and iron oxide.

[0009] A further step is: (A) The reactive M(D)Q liquid silicone resin is a liquid M(D)Q silicone resin (a-1) and its organosilicon dispersion (a-2) containing reactive functional groups of acrylate, allyl, mercapto(hydrocarbon), vinyl, hydrosilyl, epoxy(hydrocarbon), and amino(hydrocarbon). The M group of the reactive M(D)Q silicone resin includes methyl, ethyl, phenyl, and trifluoropropyl groups, and its MQ value is between 0.6 and 1.4, and the functional group content is between 0.018 and 0.15 mol. The viscosity is not greater than 80000 mPa·s, and the M(D)Q silicone resin content in the organosilicon dispersion (a-2) is not less than 37%. The organosilicon dispersion medium (a-3) is selected from at least one of the following liquids: (meth)acrylate-based polysiloxane, terminal allyl polysiloxane, divinyl polysiloxane, terminal acrylate-based polysiloxane, terminal methacrylate-based polysiloxane, mercapto-containing polysiloxane, terminal vinyl polydimethyl(methylvinyl) polysiloxane, dimethyl silicone oil, methyl phenyl silicone oil, terminal hydrogen-containing polysiloxane, terminal epoxy (hydrocarbon)-based polysiloxane, and terminal amino (hydrocarbon)-based polysiloxane. The side group of the polysiloxane is at least one of methyl, ethyl, phenyl, cyclohexyl, and trifluoropropyl. The viscosity of the organosilicon dispersion medium a-3 is not higher than 8000 mPa·s.

[0010] A further step is: (B) The water in component (B) is selected from at least one of tap water, deionized water, distilled water, well water, purified water, and mineral water, and its pH value is between 6 and 8.

[0011] A further step is: (C) The nonionic surfactant of component has an HLB value between 3.0 and 9 and is selected from at least one of the following: sorbitan sesquioleate, glyceryl monostearate, ethylene glycol monostearate, sorbitan monooleate, propylene glycol monolaurate, diethylene glycol monostearate, sorbitan monostearate, diethylene glycol stearate, diethylene glycol monolaurate, glycol monostearate, diethylene glycol monolaurate, sorbitan monopalmitate, tetraethylene glycol monostearate, polyoxypropylene stearate, sorbitan monolaurate, and polyether-modified silicone oil.

[0012] A further step is: (D) The curing agent is selected from at least one of the following: vinyl-terminated polydimethyl(methylvinyl)polysiloxane, poly(methylhydro)dimethylsiloxane, polymethylhydrosiloxane, poly(methylhydro)methylphenylsiloxane, hydrogen-terminated polydimethylsiloxane, hydrogen-terminated poly(methylhydro)dimethylsiloxane, tetramethyldisiloxane, N-β-aminoethyl-γ-aminopropylpolysiloxane, side-amino silicone oil, side-epoxy silicone oil, and 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, amino-terminated hyperbranched siloxane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, tetraethoxysilane, tetrapropoxysilane, methyltributanone oxime silane, and g-(methacryloyloxy)propyltrimethoxysilane, wherein each molecule contains not less than two reactive functional groups that are connected to silicon atoms, and the viscosity is not greater than 500 mPa·s.

[0013] A further step is: (E) The catalyst is selected from complexes of rhodium and substituted phosphine, and complexes of platinum and (cyclopentadiene, (methyl)cyclopentadiene, cyclooctadiene, acetylacetone, substituted phosphine, non-conjugated olefins), dibutyltin dilaurate, stannous octoate, acetophenone, benzophenone, benzoin diether, 2,2-dimethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-[(4-tert-butyl)phenyl]-1-propanone, triaryliodohexafluorophosphate iodonium salt, diphenyliodohexafluorophosphate, At least one of 4-phenylthiophenyl diphenylthioium salts; the non-conjugated olefin includes at least one of 1,3-divinyl-1,3-diphenyl-dimethyldisiloxane, 1-hydroxy-3-vinyl-tetramethyldisiloxane, tetramethyldivinyldisiloxane, tetramethyltetravinylcyclotetrasiloxane, propylene, cyclohexene, hexene, vinylsiloxane, and vinylcyclosiloxane, wherein the substituent of the substituted phosphine is at least one of phenyl, tert-butyl, cyclohexyl, ethynyl, and chlorine atoms.

[0014] A further step is: (F) The curing accelerator is selected from at least one of 2,4,6-trimethylbenzoyl diphenylphosphine oxide, hexaallyl-m-phenyltricarboxamide, dimethyl azobenzene-4,4¢-dicarboxylate, N-phenyl-1,2,4-triazolidinedione, N-methyl-1,2,4-triazolidinedione, naphthalene, maleic acid ester, alkynyl alcohols with 4 to 9 carbon atoms and their silanized products, 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, polyvinylsiloxane, and polyvinylcyclosiloxane.

[0015] A further step is: The nanofibers / particles of component (G) are selected from at least one of aramid nanofibers, carbon nanotubes, hydrophobic silica particles, white hyaluronic acid, and nano iron oxide, wherein the carbon content of the hydrophobic silica is not less than 1.5%.

[0016] This invention also provides a method for preparing a flexible, highly porous foam material, which utilizes the photo / thermal curable moldable reactive liquid silicone resin emulsion composition provided in this application, and is mainly carried out according to the following steps: a. A viscous two-phase aqueous emulsion is formed by high-speed mechanical (emulsification) dispersion of reactive liquid M(D)Q silicone resin, water (including nanofiber aqueous dispersion), and nonionic surfactant. Curing agent, accelerator, catalyst, etc. are added and rapidly mixed and dispersed into a uniform emulsion. b. Load the silicone resin aqueous emulsion into a centrifuge or vacuum planetary mixer container, rotate it quickly to mix it evenly, and remove air bubbles under centrifugation or centrifugation with vacuum. c. Place the water-containing emulsion containing air bubbles under ultraviolet light, at room temperature for a long time, or in an oven or other container at a temperature not exceeding 100°C for pressureless curing. During molding, slowly inject the centrifugally degassed emulsion into the mold cavity under pressure and heat and pressurize it at a temperature not exceeding 100°C. Finally, remove the shaped foam product and dry it at a low temperature to obtain the flexible liquid silicone resin foam material with high porosity.

[0017] According to the present invention, a moldable flexible liquid silicone resin foam material with high interconnectivity can be obtained. Regardless of whether molding, injection molding, centrifugal casting, or rotational casting is used, a liquid silicone resin foam material with high interconnectivity, fine pores, strong load-bearing capacity, stable process, and good appearance can be obtained.

[0018] Based on the foregoing introduction of the basic scheme of the present invention, the applicant further provides the optimal scheme for implementing the present invention, as follows: -Component (A)- Component (A) consists of a reactive M(D)Q liquid silicone resin (a-1) and an organosilicon dispersion (a-2) containing reactive functional groups FGR of (meth)acrylate, allyl, mercapto(hydrocarbon), vinyl, hydrosilyl, epoxy(hydrocarbon), and amino(hydrocarbon) groups. The M groups of the reactive M(D)Q silicone resin include methyl, ethyl, phenyl, and trifluoropropyl groups, with an MQ value between 0.6 and 1.4 and a functional group content between 0.018 and 0.15 mol / L. The viscosity is not greater than 80000 mPa·s, and the resin content in the dispersion is not less than 37%. The organosilicon dispersion medium (a-3) is selected from at least one of the following: (meth)acrylate-based polysiloxane, terminal allyl polysiloxane, terminal vinyl polysiloxane, terminal acrylate-based polysiloxane, terminal methacrylate-based polysiloxane, mercapto polysiloxane, terminal vinyl polydimethyl(methylvinyl)polysiloxane, dimethyl silicone oil, methyl phenyl silicone oil, terminal hydrogen-containing poly(methylhydrogen)dimethylsiloxane, terminal epoxy (hydrocarbon)-based polysiloxane, and terminal amino (hydrocarbon)-based polysiloxane. The side group of the polysiloxane is at least one of methyl, ethyl, phenyl, cyclohexyl, and trifluoropropyl. The viscosity of the organosilicon dispersion medium a-3 is not higher than 8000 mPa·s.

[0019] Among them, the reactive liquid M(D)Q silicone resin (a-1) is composed of monofunctional chain segments (R3SiO2). 0.5M(D)Q silicone resin is a highly branched, three-dimensional (non-linear) polyorganosiloxane or its dispersion, consisting of a difunctional unit (D) [-(R)2SiO-], a tetrafunctional linker (-SiO2-, code Q), and an active functional group FGR. It is composed of these components and a Si-O bond backbone. Compared to reactive MQ silicone resin, reactive MDQ silicone resin exhibits better flexibility and elongation properties. M(D)Q silicone resin is mainly synthesized using the water glass method and the tetraethyl orthosilicate method, and is prepared using acid-catalyzed hydrolysis condensation polymerization, alkali-catalyzed hydrolysis condensation polymerization, and metal salt-catalyzed condensation polymerization. Introducing reactive functional groups into M(D)Q silicone resin can improve its reactivity and curing effect, regulate the adhesion properties of the substrate, and significantly improve its mechanical strength.

[0020] In the synthesis of reactive liquid M(D)Q silicone resin, bifunctional organosilicon materials such as dimethyldiethoxysilane, diphenyldimethoxysilane, diethyldiethoxysilane, and bis(trifluoropropyl)diethoxysilane can be selected, as well as phenyltriethoxysilane, methyltrimethoxysilane, vinyltriethoxysilane, allyltriethoxysilane, g-(methacryloyloxy)propyltrimethoxysilane, g-(methacryloyloxy)propyltriethoxysilane, and g-epoxypropyltriethoxysilane can be selected. Using trifunctional organosilicon materials such as triethoxysilane, trimethoxysilane, triethoxysilane, mercaptopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, 3-epoxypropoxypropylmethyldimethoxysilane, γ-glycidyl etheroxypropyltrimethoxysilane, and β-3,4-epoxycyclohexylethyltrimethoxysilane as raw materials, solvent-free organosilicon resins with various properties that can flow at room temperature are synthesized.

[0021] Reactive liquid M(D)Q silicone resin has an inorganic Si-O backbone and saturated organic side groups or reactive functional groups. It possesses heat resistance, water repellency, cold resistance, film-forming properties, flexibility, and adhesion that are difficult for ordinary organic resins to achieve, as well as solvent resistance, acid resistance, and alkali resistance. Furthermore, it exhibits excellent electrical insulation and mechanical properties, and is widely used in the reinforcement of liquid adhesives, tackifiers, pressure-sensitive adhesives, coatings, and other fields, possessing high industrial value. Examples of reactive liquid M(D)Q silicone resin include vinyl liquid MDQ silicone resin produced by Shanghai Aishengbo Organosilicon New Materials Co., Ltd., with an M / Q ratio of 0.8, a vinyl content of 0.11 mol%, and a viscosity of 6000 mPa·s.

[0022] The dispersion (a-2) of the vinyl M(D)Q silicone resin is a dispersion of liquid or solid vinyl M(D)Q silicone resin in a liquid organosilicon dispersion medium. The liquid organosilicon dispersion medium is selected from at least one of the following: terminal vinyl poly(dimethyl, diethyl, methylphenyl)siloxane, terminal allyl polysiloxane, terminal acrylate polysiloxane, terminal methacrylate polysiloxane, terminal vinyl polydimethyl(methylvinyl)polysiloxane, dimethyl silicone oil, terminal methyl polymethylvinylsiloxane, methylphenyl silicone oil, and terminal methyl polymethylphenylvinylsiloxane. The viscosity of the organosilicon dispersion medium a-3 is not higher than 8000 mPa·s. The terminal groups of the terminal vinyl polysiloxane are dimethylvinylsiloxane, divinylmethylsiloxane, etc., which can participate in crosslinking reactions, and the terminal (meth)acrylate groups are (meth)acrylate propoxydimethylsiloxane or di(meth)acrylate propoxydimethylsiloxane. The polysiloxanes include polydimethylsiloxane, polydiethylsiloxane, polydihexylsiloxane, and polytrifluoropropylsiloxane. The dispersion medium can be selected from materials with good compatibility and reactivity, such as terminal vinyldimethyl silicone oil, terminal vinylmethylphenyl silicone oil, terminal vinyltrifluoromethyl silicone oil, and terminal vinylmethyl diphenyl silicone oil; there are no other specific limitations.

[0023] There are no restrictions on the preparation method of the organosilicon dispersion medium (a-3). There are no specific restrictions on the molecular chain or end group / side group structure of the polysiloxane in the organosilicon dispersion medium (a-3). Polysiloxanes with a single side group or different molecular chain / side group / end group structures are acceptable. Mixtures of two or more functional polysiloxanes with single or different molecular weights (viscosities) are acceptable, preferably with a viscosity not exceeding 8000 mPa·s.

[0024] There are no specific restrictions on the preparation method of reactive liquid M(D)Q silicone resin (component A). Reactive liquid M(D)Q silicone resin can be synthesized directly, or the reactive M(D)Q silicone resin powder can be uniformly dispersed in a liquid organosilicon medium. There are also no specific restrictions on the preparation method of reactive MQ silicone resin dispersion. Solvent dissolution-mixing-(low-pressure) distillation or vacuum evaporation to remove the solvent can be used, as well as room temperature mixing-high-temperature melting-kneading dispersion or other methods. For reactive liquid M(D)Q silicone resin (a1) and reactive M(D)Q silicone resin dispersion (a2), if the resin content is high or the flexibility is insufficient during use, an organosilicon dispersion medium (a-3) that does not affect its curing can be added for further dispersion. As long as the reactive M(D)Q silicone resin content is not less than 37% and the functional group content is within the specified range of component A, suitable results can be achieved. Reactive liquid M(D)Q silicone resin can be used directly without the need for solvent dispersion and subsequent solvent removal. Compared to solid organosilicon resin powder, it is easier to use in industry, has a wider range of applications, and better application prospects. Examples of reactive liquid M(D)Q silicone resin dispersions include the vinyl liquid MQ silicone resin dispersion produced by Shandong Dayi Chemical Co., Ltd., with an M / Q ratio of 0.8, a vinyl content of 0.05 mol%, and a viscosity of 8000 mPa·s; and the vinyl liquid MQ silicone resin produced by Zhejiang Ningbo Runhe Organosilicon New Material Co., Ltd., with an M / Q ratio of 0.8, a vinyl content of 0.05 mol%, and a viscosity of 6000 mPa·s.

[0025] The reactive liquid M(D)Q silicone resin of component (A) can be a single molecular chain structure, or a mixture of two or more reactive liquid M(D)Q silicone resins and their organosilicon dispersions with different molecular chain structures or different viscosity-uniform polymerization degrees.

[0026] The reactive liquid M(D)Q silicone resin has an MQ value between 0.6 and 1.4, preferably between 0.8 and 1.2; a functional group content between 0.018 and 0.16 mol%, preferably between 0.022 and 0.11 mol%; a viscosity not greater than 80000 mPa×s, preferably between 2000 and 50000 mPa×s, more preferably between 3000 and 10000 mPa×s; and a resin content not less than 37%, preferably not less than 45%. As long as its indicators are within the corresponding range or even the preferred range, good results can be obtained.

[0027] Component (B) The water in component (B) is a physically porous component in the highly porous flexible silicone resin foam material. Component (B) is selected from at least one of tap water, deionized water, distilled water, well water, purified water, and mineral water, with a pH value between 6 and 8 and a content greater than 98%. If the nanofiber material (aramid nanofiber, carbon nanotube) is an aqueous dispersion, the water content is included in the amount of component (B).

[0028] Component (B) is preferably tap water, distilled water, or purified water.

[0029] The amount of component (B) is between 50 and 300 parts by weight, preferably 60 to 200 parts by weight, and more preferably 80 to 150 parts by weight.

[0030] Component (C) The nonionic surfactant in component (C) is a special surface-active substance for obtaining flexible, highly porous silicone resin foam materials. The nonionic surfactant in component (C) is characterized by an HLB value between 3.0 and 9, and is selected from at least one of the following: sorbitan sesquioleate, glyceryl monostearate, ethylene glycol monostearate, sorbitan monooleate, propylene glycol monolaurate, diethylene glycol monostearate, diethylene glycol monostearate, diethylene glycol monolaurate, glycol monostearate, diethylene glycol monolaurate, sorbitan monopalmitate, polyoxypropylene stearate, tetraethylene glycol monostearate, sorbitan monolaurate, and polyether-modified silicone oil. There are no restrictions on the type of polyether-modified silicone oil. Any type of modified silicone oil, such as polyoxyethylene, polyoxypropylene, or a mixture thereof, is acceptable. It can be either Si-OC or Si-C type. Its viscosity is between 200 mPa.s and 5000 mPa.s. As long as its HLB value meets the requirements, satisfactory emulsion dispersion and good molding effect can be obtained.

[0031] Component (C) is preferably sorbitan monostearate, diethylene glycol monolaurate, sorbitan monopalmitate, sorbitan monooleate, and polyether-modified silicone oil.

[0032] The nonionic surfactant described in this invention is an essential or effective component for achieving the purpose of this invention. Without this component, it is difficult to obtain the desired effect. The addition of other surfactant components cannot negate the effectiveness of this invention regarding nonionic surfactants.

[0033] The amount of component (C) added should preferably be 0.1 to 12 parts by mass of organic polymer per 100 parts by mass of component (A).

[0034] -Component (D)- The curing agent of component (D) is selected from at least one of the following: vinyl-terminated poly(methylvinyl)dimethylpolysiloxane, poly(methylhydro)dimethylsiloxane, polymethylhydrosiloxane, poly(methylhydro)methylphenylsiloxane, hydrogen-capped polydimethylsiloxane, hydrogen-capped poly(methylhydro)dimethylsiloxane, tetramethyldisiloxane, N-β-aminoethyl-γ-aminopropylpolysiloxane, side-amino silicone oil, side-epoxy silicone oil, and 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, amino-terminated hyperbranched siloxane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, tetraethoxysilane, tetrapropoxysilane, methyltributanone oxime silane, and g-(methacryloyloxy)propyltrimethoxysilane, wherein each molecule contains not less than two reactive functional groups that are connected to silicon atoms, and the viscosity is not greater than 500 mPa·s.

[0035] The curing agent can be a single molecular structure, or a mixture of two or more organopolysiloxanes with different molecular structures and varying contents of functional groups (such as 1.1 mol% and 0.1 mol%), such as a composition of different hydrogen-containing (poly)siloxanes, such as a mixture of hydrogen-containing silicone oil (poly(methylhydro)dimethylsiloxane) with 0.5% hydrogen content and tetramethyldisiloxane.

[0036] There is no specific limit to the average functional group content (based on functional groups directly bonded to silicon atoms) of component (D) curing agent, but it is preferable to ensure that the reactive liquid silicone resin of component (A) is fully cured. The viscosity of component (D) curing agent is not greater than 500 mPa·s, preferably not greater than 200 mPa·s, and more preferably not greater than 100 mPa·s.

[0037] The amount of component (D) curing agent composition added is preferably 0.5 to 20 parts by weight of reactive organosilicon resin per 100 parts by weight of component (A), and more preferably 3 to 15 parts by weight. As long as the amount of component (D) is within this range, the moldability, curing effect, physical and mechanical properties, high porosity, and flexibility of the liquid silicone resin foam can reach a satisfactory level.

[0038] Component (E) The catalyst of component (E) is characterized by being selected from complexes of rhodium and substituted phosphine, and complexes of platinum and (cyclopentadiene, (methyl)cyclopentadiene, cyclooctadiene, acetylacetone, substituted phosphine, non-conjugated olefins), dibutyltin dilaurate, stannous octoate, acetophenone, benzophenone, benzoin diether, 2,2-dimethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-[(4-tert-butyl)phenyl]-1-propanone, triaryliodohexafluorophosphate iodonium salt, and diphenyliodohexafluorophosphate. At least one of 4-phenylthiophenyl diphenylthioium salt; the non-conjugated olefin includes at least one of 1,3-divinyl-1,3-diphenyl-dimethyldisiloxane, 1-hydroxy-3-vinyl-tetramethyldisiloxane, tetramethyldivinyldisiloxane, tetramethyltetravinylcyclotetrasiloxane, propylene, cyclohexene, hexene, vinylsiloxane, and vinylcyclosiloxane, wherein the substituent of the substituted phosphine is at least one of phenyl, tert-butyl, cyclohexyl, ethynyl, and chlorine atom.

[0039] The non-conjugated olefins are non-p-bonded conjugated olefins, regardless of the number of olefin groups in a single molecule. There are no specific restrictions on the preparation or technical methods for platinum complexes with (methyl)cyclopentadiene, cyclooctadiene, acetylacetone, or non-conjugated olefins. For example, reactions of chloroplatinic acid (H₂PtCl₆×H₂O) with various alcohols (isopropanol, cyclohexanol, hexanol), reactions with divinyltetramethyldisiloxane followed by alkali washing, or the formation of platinum complexes followed by ligand exchange are all acceptable.

[0040] Specifically, platinum catalysts include complexes of platinum metal and alkene compounds such as methylcyclopentadiene platinum, trimethyl(methyl)cyclopentadiene platinum (IV), Karstedt catalyst ([(CH2=CHSiMe2)2O]2Pt) – the reaction product of H2PtCl6 with tetramethyldivinylsiloxane (DVDM) and NaHCO3, Willing catalyst – the product of H2PtCl6 reacting with tetramethyldivinylsiloxane and then washing with water to remove acid, (PPh3)2Pt-(CH2=CH2), isopropanol solution of chloroplatinic acid (H2PtCl6×H2O) (Sperier catalyst), hexanol solution of chloroplatinic acid, cyclohexanol solution of chloroplatinic acid, and platinum acetylacetonate (II).

[0041] Component (E) is preferably platinum-tetramethyldivinyldisiloxane complex ([(CH2=CHSiMe2)2O]2Pt), platinum-tetramethyltetravinylcyclotetrasiloxane complex, platinum-1,3-divinyl-1,3-diphenyl-dimethyldisiloxane complex, Karstedt catalyst, Willing catalyst, platinum(II) acetylacetonate, and trimethyl(methyl-cyclopentadienyl)platinum.

[0042] There are no restrictions on the concentration of component (E) (such as 1000ppm or 5000ppm for precious metals) and diluent. Diluents such as inert silicone oil or reactive silicone oil such as vinyl-terminated silicone oil are acceptable, as long as they are evenly dispersed, odorless, and do not affect the activity of the precious metal catalyst in the curing reaction.

[0043] The amount of component (E) added should be appropriate for every 100 parts by mass of reactive liquid M(D)Q silicone resin of component (A). For precious metal catalysts, it is recommended that the concentration of precious metals not exceed 100 ppm (ppm is the abbreviation for parts per million, based on the mass of precious metals). The preferred amount is 5-30 ppm, more preferably 7-20 ppm, to balance suitable curing speed and economy. As long as the amount of component (E) is within this range, the processing quality and physical and mechanical properties of the liquid silicone resin foam can achieve satisfactory results.

[0044] Component (E) is preferably methylcyclopentadiene platinum, trimethyl(methyl)cyclopentadiene platinum (IV), Karstedt catalyst, platinum-tetramethyldivinyldisiloxane complex, benzophenone, 2,2-dimethoxy-2-phenylacetophenone, benzoin diether, dibutyltin dilaurate, etc.

[0045] Component (F) The accelerator of component (F) is selected from at least one of 2,4,6-trimethylbenzoyl diphenylphosphine oxide, hexaallyl-m-phenyltricarboxamide, dimethyl azobenzene-4,4¢-dicarboxylate, N-phenyl-1,2,4-triazolidinedione, N-methyl-1,2,4-triazolidinedione, naphthalene, maleic acid ester, alkynyl alcohols with 4-9 carbon atoms and their silanized products, 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, polyvinylsiloxane, and polyvinylcyclosiloxane.

[0046] Examples of the maleic esters include monopropyl maleate, monoethyl maleate, monoallyl maleate, diallyl maleate, and 2-ethylhexyl maleate. The alkynols with 4 to 9 carbon atoms are specifically selected from 1-butynol, 1-methylbutynol, 1-pentynol, 3,3-dimethylpentynol, 1-hexynol, 1-ethynylcyclohexanol, 3-methyl-1-butyn-3-ol, 3-methyl-1-pentyn-3-ol, 3-hexyn-1-ol, and 3,5-dimethyl-1-hexyn-3-ol. Examples of the reactants of alkynols with 4-9 carbon atoms and silanes include tris-(3-methyl-1-butyn-3-oxy)methylsilane, trimethyl(3-((trimethylsilyl)oxy)prop-1-yn-1-1-yl)silane, tris-(3-methyl-1-butyn-3-oxy)vinylsilane, and 3-methyl-3-trimethylsilyloxy-1-butyn. Examples of polyvinylcyclosiloxanes include tetramethyltetravinylcyclotetrasiloxane, trimethyltrivinylcyclotrisiloxane, pentamethylpentavinylcyclopentasiloxane, and divinylcyclotetrasiloxane.

[0047] Component (F) is preferably 2,4,6-trimethylbenzoyl diphenylphosphine oxide, polyvinylcyclosiloxane, methylbutynol, 3,3-dimethyl-pentynol, 1-ethynyl-cyclohexanol, 3-methyl-1-butyn-3-ol, etc.

[0048] The amount of component (F) added is preferably 0 to 0.5 parts by mass per 100 parts by mass of reactive liquid M(D)Q silicone resin of component (A), more preferably 0.05 to 0.25 parts by mass, and more preferably 0.08 to 0.2 parts by mass. As long as the amount of component (F) is within this range, the processability and physical and mechanical properties of the flexible high-porous liquid silicone resin foam can reach an acceptable level.

[0049] -Component (G)- Component (G) nanofibers / particles are used to provide the functionality (thermal conductivity, electrical conductivity, antistatic properties) and improved mechanical properties of liquid silicone resin foam materials, as well as better creep resistance. The nanofibers / particles of component (G) are selected from at least one of aramid nanofibers, carbon nanotubes, white hyaluronic acid, hydrophobic silica particles, and nano-iron oxide, wherein the carbon content of the hydrophobic silica particles is not less than 1.5%.

[0050] The aramid nanofibers in component (G) are para-aramid nanofibers with a diameter of 10–100 nm and an aspect ratio of approximately 3000, a logarithmic viscosity of 2.0–5.0 dL / g, and a solid content of 2.0–4.0%. The carbon nanotubes are single-walled or multi-walled carbon nanotubes (CNTs) with a diameter of 0.6–100 nm. There are no restrictions on the functional groups and dispersants on the surface of the carbon nanotubes. There are no particular restrictions on the application forms of hydrophobic nano-silica, nano-aramid fibers, and carbon nanotubes, except that organic solvents are not used as a medium. They can be in powder form, aqueous dispersion, or liquid polysiloxane dispersion. For example, nano-aramid fibers are commercially available as a 2–4% aqueous dispersion. When using them, there is no need to remove the water. They can be directly dispersed in water and then mixed with component (A). Due to differences in surface energy and affinity, they can be rapidly transferred into liquid organosilicon M(D)Q resin and organosilicon dispersion, which can achieve reinforcement and functionalization of liquid silicone resin materials.

[0051] (G) The hydrophobic silica particles in the component are selected from at least one of hydrophobic vapor-phase silica, hydrophobic precipitated silica, sol-gel hydrophobic nano silica, etc., and there is no specific limitation on the specific surface area of ​​the hydrophobic nano SiO2.

[0052] To ensure good flowability of the reactive liquid silicone resin, the carbon content of the hydrophobic nano-oxide particles is not less than 1.5%, more preferably not less than 2%. Examples of hydrophobic nano-inorganic oxide particles include materials such as silica that have undergone pre-reaction treatment under gas-phase or liquid-phase conditions with hexamethyldisilazane, hexamethylcyclotrisilazane, octamethylcyclotetrasiloxane, etc., have a high surface carbon content (greater than 1.8%), and exhibit high affinity for non-polar oils, such as Wacker's R-812S, Yichang Kelin Company's TB630 silica, and the Institute of Physics and Chemistry, Chinese Academy of Sciences' IPC220 hydrophobic fumed silica.

[0053] (G) Component Baiyanhua is ultrafine activated calcium carbonate with a particle size of no more than 0.08 micrometers and a specific surface area of ​​no less than 20 m² / g. Its surface is treated with stearic acid or resin acid, cationic surfactants, etc., and it has good affinity with rubber, resin, etc. Its commercial names include Baiyanhua, Baiyanhua, etc., and the preferred particle size is no more than 0.08 micrometers. Nano iron oxide consists of Fe₂O₃ particles with a particle size of no more than 100 nanometers. There are no special requirements for the surface and type of nano iron oxide; types a, b, and g can all be used.

[0054] The nanofibers / particles of component (G) can be mixed using various machines such as kneaders and mechanical stirrers. When using hydrophobic silica particles, there is no need for on-site hydrophobic treatment or removal of volatile substances. When using nanofiber aqueous dispersions, mechanical mixers are preferred to ensure that they are dispersed evenly with components A, B or their mixtures, thereby achieving the reinforcement and functionalization of liquid organosilicon resin materials.

[0055] The amount of nanofibers / particles added to component (G) is preferably 0 to 16 parts by mass per 100 parts by mass of reactive liquid M(D)Q silicone resin of component (A), and more preferably 5 to 10 parts by mass. As long as the amount of nanofibers / particles is within this range, the processability, physical and mechanical properties, and functionality of the liquid silicone resin foam can reach an acceptable level.

[0056] -Other components- The present invention may also include heat-resistant additives such as micron-sized iron oxide and micron-sized cerium dioxide; micron-sized thermally conductive fillers such as boron nitride, aluminum oxide, and zinc oxide; softeners such as liquid paraffin, methyl silicone oil, phenyl silicone oil, and paraffin oil; and organic or inorganic (iron yellow, iron black, etc.) coloring substances such as pigment orange, phthalocyanine green, permanent red, and permanent yellow.

[0057] -Preparation Method of High-Porosity Foam Material- The preparation method of high-pority foam material mainly follows these steps: a. The reactive liquid M(D)Q silicone resin, water (nanofiber aqueous dispersion), and nonionic surfactant are dispersed by high-speed mechanical (emulsification) to form a two-phase aqueous emulsion. Then, curing agent, accelerator, catalyst, etc. are added and quickly mixed and dispersed to form a uniform emulsion. b. Place the aqueous emulsion into a centrifuge or vacuum planetary mixer container, rotate it quickly to mix it evenly, and remove air bubbles under centrifugation or centrifugation with vacuum. c. Place the water-containing emulsion containing air bubbles under ultraviolet light, at room temperature for a long time, or in an oven or other container not exceeding 100°C to cure. During molding, slowly inject the centrifugally degassed emulsion into the mold cavity under pressure and heat and pressurize it at not exceeding 100°C. Finally, take out the shaped foam product and dry it at low temperature to obtain a flexible liquid silicone resin foam material with a wide density range and high porosity.

[0058] There are no particular restrictions on the method of adding component (B) – water – in step (a). Water can be added together with the nonionic surfactant when mixing with the reactive liquid M(D)Q silicone resin, or it can be added after the other components other than water have been mixed until they are generally uniform in appearance. As long as water and nonionic surfactant are mixed together at high speed or for a long time, a uniform, non-drip paste-like emulsion dispersion effect can be obtained.

[0059] There are no particular restrictions on the method of incorporating component (G) nanofibers / particles in step (a). Hydrophobic nano-inorganic oxide particles can be first mixed into the reactive liquid M(D)Q silicone resin (a-1) or the organosilicon dispersion medium (a-3) before mixing, or they can be added after water and the reactive liquid M(D)Q silicone resin have been mixed to form a viscous white emulsion, thus obtaining a mixture of hydrophobic nanoparticles and reactive liquid silicone resin. Both methods can achieve ideal dispersion and a soft, highly porous organosilicon foam material. Nano-aramid fibers and carbon nanotubes can be added directly in the form of an aqueous dispersion or powder, with the amount of water in the aqueous dispersion included in the amount of component (B). There are no specific restrictions on the rapid mixing method of the materials; any equipment such as a mechanical stirrer, planetary stirrer, high-speed mixer, or (ultra)high-speed emulsifying disperser can be used, as long as the silicone oil and water are rapidly and uniformly mixed without separation.

[0060] The liquid silicone resin emulsion composition of this invention is a pseudo-Bingham fluid or a yield pseudoplastic fluid with a yield pressure between 3 and 20 Pa. It exhibits poor self-flow and leveling properties, requiring the removal of air bubbles using the (vacuum) centrifugation and (vacuum) planetary stirring methods described in this invention before transfer molding, injection molding, or centrifugal casting can be performed to ensure the uniformity of the internal pores. There are no special limitations on the molding method of the liquid silicone resin emulsion composition of this invention; centrifugal casting, compression molding, injection molding, or transfer molding can all be used. Centrifugal casting, compression molding, and injection molding are preferred, as they all achieve a fine, uniform, and elastic pore structure with stable foaming and good repeatability. There are no special limitations on the molding pressure conditions of the liquid silicone resin emulsion composition of this invention; pressureless curing or pressure curing is acceptable, as long as the required pressure is sufficient to fill the mold and maintain the desired shape of the mold cavity.

[0061] The ultraviolet light irradiation of the aqueous emulsion described in this invention is not limited by the source of the ultraviolet light; either sunlight or a dedicated device for generating ultraviolet light is acceptable. There are no restrictions on the duration of ultraviolet light irradiation or the subsequent heat curing time. The room temperature curing of the aqueous emulsion described in this invention is limited to an ambient temperature of 5°C to 35°C (preferably 15°C to 30°C) and a time of 0.5 to 3 days (preferably 1 to 1.5 days). As long as the temperature and time are within these ranges, satisfactory molding results can be obtained.

[0062] The low-temperature drying conditions for the shaped (aqueous) foam products described in this invention are limited to a temperature not exceeding 150°C, more preferably not exceeding 130°C, and even more preferably not exceeding 120°C. There are no restrictions on the drying procedure or time for the (aqueous) foam products; there are no limitations on the temperature and time for one, two, or even three stages of drying, as long as the fastest drying time is achieved and there is no significant moisture inside the foam. Detailed Implementation

[0063] The present invention will now be described in detail with reference to a series of embodiments and comparative examples, but the present invention is not limited in any way to the following embodiments. In the following embodiments, "parts" refers to "parts by mass".

[0064] Example 1

[0065] 83.3 parts by weight of reactive liquid MDQ silicone resin with vinyl functional groups (vinyl functional group content 0.11 mol%, MQ value 0.8, viscosity 5000 mPa×s, manufactured by Shanghai Aispo Silicone Materials Co., Ltd.) and 16.7 parts by weight of α,W-terminated vinyl polydimethylsiloxane (viscosity 1000 mPa.s, produced by Zhejiang Quzhou Jiancheng Silicone Co., Ltd.) were rapidly mixed evenly to obtain a reactive liquid silicone resin dispersion with a resin content of 83%. Then, 100 parts by weight of tap water (pH value 7.0), 1.0 parts by weight of the dispersion of carbon nanotubes, and 1.2 parts by weight of diethylene glycol monolaurate (HLB value 6.1) were added and rapidly stirred to form a uniform paste-like emulsion. Then, add 5.8 parts by weight of liquid hydrogen-containing silicone oil (poly(methylhydrogen)dimethylsiloxane, viscosity 30 mPa.s, hydrogen content 0.75%, produced by Shenzhen Lianhuan Organosilicon Co., Ltd.), 0.04 parts by weight of 3,5-dimethyl-1-ethyn-3-ol (produced by Maclean, purity not less than 97%), 0.13 parts by weight of tetramethyltetravinylcyclotetrasiloxane (produced by Zhonghao Chenguang Chemical Research Institute, purity not less than 99%), and 0.17 parts by weight of platinum catalyst (VM-23, platinum complex catalyst, the main components are [(CH2=CHSiMe2)2O]3Pt2 and [(CH2=CHSiMe2)2O]Pt[CH2=CHSiME2OSiMe2OH], Pt mass fraction 3000ppm, produced by Zhejiang Quzhou Jiancheng Organosilicon Co., Ltd.) to the emulsion. Mix in a beaker at room temperature with a mechanical stirrer at a speed of 500-1000 rpm until the appearance is uniform and no water droplets leak out.

[0066] The above-mentioned uniformly mixed paste emulsion is transferred into a (vacuum) centrifuge container and centrifuged at 1000-2000 rpm for 1-4 min (internal pressure 20-100 kPa). The resulting paste emulsion is then cured at a constant temperature in an oven at 70-80°C. When molding is required, the paste emulsion is transferred into a centrifuge tube and centrifuged at 1000-3000 rpm for 2-4 min to remove air. The emulsion is then injected into a mold cavity (e.g., F20mm×20mm) and molded and cured at 60-85°C for 0.5-2 h or at room temperature for 1-3 days. The cured liquid silicone foam material is then removed and dried in an oven at 70°C and 150°C for 2-3 h and 2-4 h respectively to completely remove moisture from the foam, thus obtaining the flexible high-porous liquid silicone resin foam material described in this patent.

[0067] The obtained flexible liquid silicone rubber foam material was tested for Shore C hardness according to GB / T531-1999, and the foam density was determined according to GB / T533-2008. For centrifugally cast foam, foam sheets of 1mm to 2mm thickness were obtained by slitting. The cell size was observed under an optical or electron microscope. The hardness of the pressed F20×20mm foam cylinders was tested using a Shore C hardness tester. Fluid (e.g., water) displacement was performed using a vacuum degassing method to test the foam continuity rate (calculated as: continuity rate = ((m2-m1) / r)). w ) / (m1 / r1-m1 / r0), where m1 and r1 are the foam mass and density, r0 is the density of solid glue, m2 is the foam mass after vacuum degassing and fluid replacement, and r w To replace the density of the fluid, the F20×20mm foam cylinder was pressurized to 50% strain for 72 hours at room temperature and then unloaded for 15 minutes to test the compression set. The F20×20mm foam cylinder was placed in a paper cup containing 20% ​​colored liquid paraffin / water to test the oil absorption value (in g / g, 30 minutes).

[0068] Example 2

[0069] 90.9 parts by weight of reactive liquid MDQ silicone resin with vinyl functional groups (vinyl functional group content 0.11 mol%, MQ value 0.8, viscosity 5000 mPa·s, manufactured by Shanghai Aispo Silicone Materials Co., Ltd.) and 9.1 parts by weight of α,w-terminated vinyl polydimethylsiloxane (viscosity 1000 mPa·s, produced by Zhejiang Quzhou Jiancheng Silicone Co., Ltd.) were rapidly mixed evenly to obtain a reactive liquid silicone resin dispersion with a silicone resin content of 90%. Then, 133 parts by weight of tap water and 1.35 parts by weight of diethylene glycol monolaurate (HLB value 6.1) were added and rapidly mixed evenly. Finally, a carbon content of 2.3% and a BET specific surface area of ​​175 m² were added. 29.1 parts by mass of hydrophobic fumed silica (produced by Beijing Institute of Physics and Chemistry, Chinese Academy of Sciences) were mixed evenly, and then 8.2 parts by mass of liquid hydrogen-containing silicone oil (poly(methylhydrogen)dimethylsiloxane, viscosity 30 mPa.s, hydrogen content 0.75%, produced by Shenzhen Lianhuan Organosilicon Co., Ltd.) and 0.02 parts by mass of acetylacetone platinum catalyst (97%, produced by Aladdin) were added. The mixture was then stirred evenly in a beaker at room temperature using a mechanical stirrer and an ultra-high speed disperser at speeds of 500-2000 rpm and 6000-10000 rpm to obtain a paste-like emulsion.

[0070] The uniformly mixed material is transferred into a centrifuge container and centrifuged (vacuum). The degassed paste emulsion is then squeezed into a light-transmitting mold or evenly coated onto a flat plate as needed. It is then irradiated in an ultraviolet light box for 10–30 minutes, cured at room temperature for a sufficient time, and dried at 70–150°C until all moisture is removed to obtain a liquid silicone resin foam material with fine pore size and high bubble-connecting rate.

[0071] Example 3

[0072] 100 parts by weight of reactive liquid MQ silicone resin with vinyl functional groups (vinyl functional group content 0.038 mol%, MQ value 0.8, viscosity 5000 mPa·s, resin content 50%, manufactured by Zhejiang Runhe Organosilicon New Material Co., Ltd.), 6 parts by weight of liquid hydrogen-containing silicone oil (viscosity 30 mPa·s, hydrogen content 0.75%, produced by Shenzhen Lianhuan Organosilicon Co., Ltd.), and 0.07 parts by weight of platinum catalyst (VM-23, platinum catalyst, Pt mass fraction 3000 ppm, manufactured by Zhejiang Quzhou Jiancheng Organic Chemical Co., Ltd.) were prepared. The mixture consisted of 3.0 parts by weight of diethylene glycol monolaurate (HLB value 6.1) and 250 parts by weight of tap water. The above components were directly mixed in a beaker at room temperature using a mechanical stirrer at 500-2000 rpm and an ultra-high speed disperser at 6000-10000 rpm. After being transferred to a centrifuge container, the mixture was centrifuged at high speed for 1-4 minutes. Then, it was heated and pressurized to form the foam in the same manner as in Example 1, and the moisture in the foam was dried to obtain a liquid silicone resin foam material with good appearance and good curing.

[0073] Example 4

[0074] A 4% aqueous dispersion of nano-aramid was mixed with 75 parts by mass of tap water to obtain a 1% aqueous dispersion of nano-aramid. This dispersion was then reacted with MDQ silicone resin (vinyl content 0.11 mol%, MQ value 0.8, viscosity 5000 mPa × s), a reactive liquid with vinyl functional groups. 100 parts by weight of diethylene glycol monolaurate surfactant (HLB value 6.1) manufactured by Shanghai Aishibo Organosilicon Materials Co., Ltd. were rapidly mixed evenly to obtain a paste emulsion. Then, 6 parts by weight of liquid hydrogen-containing silicone oil (viscosity 30 mPa.s, hydrogen content 0.75%, produced by Shenzhen Lianhuan Organosilicon Co., Ltd.), 1 part by weight of tetramethyldisiloxane (produced by Shanghai Jiancheng Organosilicon Co., Ltd., polymer grade), 0.10 parts by weight of 3,5-dimethyl-1-hexyn-3-ol, and 0.25 parts by weight of platinum catalyst (VM-23, platinum catalyst, Pt mass fraction 3000 ppm, produced by Zhejiang Quzhou Jiancheng Organosilicon Co., Ltd.) were directly mixed evenly in a beaker at room temperature using a mechanical stirrer at a speed of 500-2000 rpm to obtain a paste emulsion. The mixture was then transferred to a centrifuge container and centrifuged. In the same manner as in Example 1, it was heated and pressurized to form a fully cured, highly porous liquid silicone resin foam material with good resilience was obtained.

[0075] Example 5

[0076] The reactive liquid MDQ silicone resin with vinyl functional groups (vinyl functional group content 0.11 mol%, MQ value 0.8, viscosity 5000 mPa × s) was used. 100 parts by weight of (manufactured by Shanghai Aishibo Organosilicon Materials Co., Ltd.), 0.5 parts by weight of diethylene glycol monolaurate surfactant (HLB value 6.1), 0.1 parts by weight of commercially available detergent, and 60 parts by weight of tap water were rapidly mixed evenly to obtain a paste-like emulsion. Then, 9 parts by weight of liquid hydrogen-containing silicone oil (viscosity 30 mPa·s, hydrogen content 0.75%, produced by Shenzhen Lianhuan Organosilicon Co., Ltd.), 0.15 parts by weight of tetramethyltetravinylcyclotetrasiloxane, 0.05 parts by weight of 3,5-dimethyl-1-hexyn-3-ol, and 0.17 parts by weight of platinum catalyst (VM-23, platinum catalyst, Pt mass fraction 3000 ppm, produced by Zhejiang Quzhou Jiancheng Organosilicon Co., Ltd.) were directly mixed evenly in a beaker at room temperature using a mechanical stirrer at a speed of 500-2000 rpm to obtain a paste-like emulsion. The mixture was then transferred to a centrifuge container, centrifuged and degassed, and heated and pressurized in the same manner as in Example 1 to obtain a fully cured, highly porous liquid silicone resin foam material with good resilience.

[0077] Example 6

[0078] The reactive liquid MQ silicone resin with vinyl functional groups (vinyl functional group content 0.038 mol%, MQ value 0.8, viscosity 5000 mPa × s) was used. 100 parts by weight of diethylene glycol monolaurate surfactant (HLB value 6.1) and 110 parts by weight of tap water (manufactured by Zhejiang Ningbo Runhe Organosilicon Materials Co., Ltd.) are rapidly mixed evenly to obtain a paste emulsion. Then, 6 parts by weight of liquid hydrogen-containing silicone oil (viscosity 30 mPa.s, hydrogen content 0.75%, produced by Shenzhen Lianhuan Organosilicon Co., Ltd.), 0.10 parts by weight of 3,5-dimethyl-1-hexyn-3-ol, and 0.25 parts by weight of platinum catalyst (VM-23, platinum catalyst, Pt mass fraction 3000 ppm, produced by Zhejiang Quzhou Jiancheng Organosilicon Co., Ltd.) are added. The above components are directly mixed evenly in a beaker at room temperature using a mechanical stirrer at a speed of 500-2000 rpm to obtain a paste emulsion. The mixture is then transferred to a centrifuge container, centrifuged and degassed, and heated and pressurized in the same manner as in Example 1 to obtain a fully cured, highly porous liquid silicone resin foam material with good resilience.

[0079] Comparative Example 1 100 parts by weight of α,W-terminated vinyl polydimethylsiloxane (colorless, transparent, flowing liquid, viscosity 2000 mPa×s, volatile matter 1.0%, produced by Zhejiang Quzhou Jiancheng Organosilicon Co., Ltd.) and 25 parts by weight of BET specific surface area 175 m² were mixed. 2 / g of hydrophobic fumed silica (manufactured by Beijing Institute of Physics and Chemistry, Chinese Academy of Sciences, carbon content 2.3%) was mixed evenly, and then 100 parts by weight of tap water and 2.0 parts by weight of diethylene glycol monolaurate were added. After high-speed mixing, a paste emulsion was obtained. Then, 5 parts by weight of liquid hydrogen-containing silicone oil (hydrogen content 0.75%, viscosity 20 mPa.s, produced by Shenzhen Lianhuan Organosilicon Co., Ltd.), 0.10 parts by weight of tetramethyltetravinylcyclotetrasiloxane (produced by Zhonghao Chenguang Chemical Research Institute, purity not less than 99%) and 0.17 parts by weight of platinum catalyst (VM-23 platinum catalyst, Pt mass fraction 3000ppm) were added. The mixture was mixed evenly in a beaker at room temperature with a mechanical stirrer at a speed of 500-2000 rpm.

[0080] The uniformly mixed material is transferred into a (vacuum) centrifuge container and centrifuged at 1000-2000 rpm. The centrifuged paste emulsion is cured at room temperature for 1-3 days or in an oven at 60-90°C for 1-3 hours, or it is injected into a mold cavity and heated under pressure on a plate at 60-90°C. After curing, the water-containing foam is dried at 70-150°C to obtain a well-cured liquid silicone foam material with fine pores and an isolated pore structure. Various performance characteristics are performed in the same manner as in Example 1.

[0081] Comparative Example 2 100 parts by weight of α,W-terminated vinyl polydimethylsiloxane (colorless, transparent, flowing liquid, viscosity 500 mPa×s, volatile matter 1.0%, produced by Zhejiang Quzhou Jiancheng Organosilicon Co., Ltd.) were mixed with 1.0 part by weight of diethylene glycol monolaurate and 100 parts by weight of tap water at high speed to obtain a paste-like emulsion. 4 parts by weight of liquid hydrogen-containing silicone oil (hydrogen content 0.75%, produced by Shenzhen Lianhuan Organosilicon Co., Ltd.), 0.10 parts by weight of tetramethyltetravinylcyclotetrasiloxane (produced by Zhonghao Chenguang Chemical Research Institute, purity not less than 99%), 0.17 parts by weight of platinum catalyst (VM-23, platinum catalyst, Pt mass fraction 3000 ppm), and 0.05 parts by weight of 3,5-dimethyl-1-hexyn-3-ol were added and mixed evenly. The mixture was then heated and pressurized as in Comparative Example 1 to obtain an exceptionally soft, well-cured, microporous, continuous-cell but slightly brittle liquid organosilicon foam material.

[0082] Comparative Example 3 A reactive liquid MDQ silicone resin with vinyl functional groups (vinyl functional group content 0.11 mol%, MQ value 0.8, viscosity 5000 mPa×s, manufactured by Shanghai Aispo Organosilicon Materials Co., Ltd.), 100 parts by weight of commercially available Nais Group Super Vitality Lemon Ion Degreasing Detergent (active ingredients C10-16 alkylbenzene sulfonate sodium, C10-16 alcohol polyoxyethylene ether sulfate sodium, C8-16 alkyl glucoside), and 100 parts by weight of tap water were rapidly mixed evenly to obtain an emulsion. Then, 7.0 parts by weight of liquid hydrogen-containing silicone oil (hydrogen content 0.75%, manufactured by Shenzhen Lianhuan Organosilicon Co., Ltd.), 0.05 parts by weight of 3,5-dimethyl-1-hexyn-3-ol, and 0.10 parts by weight of... A mixture of 0.17 parts by mass of tetramethyltetravinylcyclotetrasiloxane (produced by Zhonghao Chenguang Chemical Research Institute, purity not less than 99%) and 0.17 parts by mass of platinum catalyst (VM-23, platinum catalyst, Pt mass fraction 3000ppm, produced by Zhejiang Quzhou Jiancheng Organosilicon Co., Ltd.) was directly mixed in a beaker at room temperature using a mechanical stirrer at a speed of 500-2000 rpm to obtain a thin emulsion. After natural degassing, the mixture was poured into a plastic beaker and heated in a 70℃ oven for curing, ultimately yielding a partially cured, non-formed, and locally water-encapsulated liquid silicone resin material. Replacing the detergent in this comparative example with sodium dodecyl sulfonate (SDS) and polyether-modified heptamethyltrisiloxane (99%, produced by Maclean) yielded the same results.

[0083] The data for the relevant embodiments and comparative examples are shown in the table below: [Table 1]

[0084] Although the present invention has been described herein with reference to illustrative embodiments, the above embodiments are merely preferred embodiments of the present invention, and the implementation of the present invention is not limited to the above embodiments. It should be understood that those skilled in the art can devise many other modifications and implementations, which will fall within the scope and spirit of the principles disclosed in this application.

Claims

1. A photo / thermal curable moldable reactive liquid silicone resin emulsion composition, characterized in that: It includes the following components in parts by weight: (A) 100 parts by weight of reactive liquid M(D)Q silicone resin; (B) 50-300 parts by weight of water; (C) 0.1–12 parts by weight of nonionic surfactant; (D) 0.5–20 parts by weight of curing agent; (E) Appropriate amount of catalyst; (F) Accelerator 0-0.5 parts by weight; (G) Nanofibers / particles 0-16 parts by weight; The nonionic surfactant in component (C) has an HLB value between 3.0 and 9; the nanofibers / particles in component (G) are selected from at least one of nano-aramid fibers, carbon nanotubes, white hyaluronic acid, hydrophobic silica particles, and nano-iron oxide.

2. The photo / thermal curable moldable reactive liquid silicone resin emulsion composition according to claim 1, characterized in that, Component (A) comprises a reactive M(D)Q liquid silicone resin a-1 having reactive functional groups including (meth)acrylate, allyl, mercapto(hydrocarbon), vinyl, hydrosilyl, epoxy(hydrocarbon), and amino(hydrocarbon) groups, and its organosilicon dispersion a-2. The M groups of the reactive M(D)Q silicone resin include methyl, ethyl, phenyl, and trifluoropropyl groups, with an MQ value between 0.6 and 1.4 and a functional group content between 0.018 and 0.

15. The viscosity is not greater than 80000 mPa·s, and the resin content in the organosilicon dispersion a-2 is not less than 37%. The organosilicon dispersion medium a-3 is selected from at least one of the following liquids: terminal vinyl polysiloxane, terminal acrylate polysiloxane, terminal methacrylate polysiloxane, mercapto(hydrocarbon) polysiloxane, terminal vinyl polydimethyl(methylvinyl) polysiloxane, dimethyl silicone oil, methylphenyl silicone oil, terminal hydrogen-containing poly(methylhydrogen)dimethylsiloxane, terminal epoxy(hydrocarbon) polysiloxane, and terminal amino(hydrocarbon) polysiloxane. The side group of the polysiloxane is at least one of methyl, ethyl, phenyl, cyclohexyl, and trifluoropropyl. The organosilicon dispersion medium a-3 is characterized by a viscosity not higher than 8000 mPa·s.

3. The photo / thermal curable moldable reactive liquid silicone resin emulsion composition according to claim 1, characterized in that: (B) The water in component (B) is selected from at least one of tap water, deionized water, distilled water, well water, purified water, and mineral water, and its pH value is between 6 and 8.

4. The photo / thermal curable moldable reactive liquid silicone resin emulsion composition according to claim 1, characterized in that: (C) The nonionic surfactant of component has an HLB value between 3.0 and 9 and is selected from at least one of the following: sorbitan sesquioleate, glyceryl monostearate, ethylene glycol monostearate, sorbitan monooleate, propylene glycol monolaurate, diethylene glycol monostearate, sorbitan monostearate, diethylene glycol stearate, diethylene glycol monolaurate, glycol monostearate, diethylene glycol monolaurate, sorbitan monopalmitate, tetraethylene glycol monostearate, polyoxypropylene stearate, sorbitan monolaurate, and polyether-modified silicone oil.

5. The photo / thermal curable moldable reactive liquid silicone resin emulsion composition according to claim 1, characterized in that: (D) The curing agent is selected from at least one of the following: vinyl-terminated poly(methylvinyl)dimethylpolysiloxane, polymethylhydrosiloxane, poly(methylhydro)dimethylsiloxane, poly(methylhydro)methylphenylsiloxane, hydrogen-terminated polydimethylsiloxane, hydrogen-terminated poly(methylhydro)dimethylsiloxane, tetramethyldisiloxane, N-β-aminoethyl-γ-aminopropylpolysiloxane, side-amino silicone oil, side-epoxy silicone oil, and 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, amino-terminated hyperbranched siloxane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, tetraethoxysilane, tetrapropoxysilane, methyltributanone oxime silane, and g-(methacryloyloxy)propyltrimethoxysilane, wherein each molecule contains not less than two reactive functional groups that are connected to silicon atoms, and the viscosity is not greater than 500 mPa·s.

6. The photo / thermal curable moldable reactive liquid silicone resin emulsion composition according to claim 1, characterized in that: (E) The catalyst is selected from complexes of rhodium and substituted phosphine, and complexes of platinum and (cyclopentadiene, (methyl)cyclopentadiene, cyclooctadiene, acetylacetone, substituted phosphine, non-conjugated olefins), dibutyltin dilaurate, stannous octoate, acetophenone, benzophenone, benzoin diether, 2,2-dimethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-[(4-tert-butyl)phenyl]-1-propanone, triaryliodohexafluorophosphate iodonium salt, diphenyliodohexafluorophosphate, At least one of 4-phenylthiophenyl diphenylthioium salts, wherein the non-conjugated olefin comprises at least one of 1,3-divinyl-1,3-diphenyl-dimethyldisiloxane, 1-hydroxy-3-vinyl-tetramethyldisiloxane, tetramethyldivinyldisiloxane, tetramethyltetravinylcyclotetrasiloxane, propylene, cyclohexene, hexene, vinylsiloxane, and vinylcyclosiloxane, wherein the substituent of the substituted phosphine is at least one of phenyl, tert-butyl, cyclohexyl, ethynyl, and chlorine atoms.

7. The photo / thermal curable moldable reactive liquid silicone resin emulsion composition according to claim 1, characterized in that: (F) The accelerator is selected from at least one of 2,4,6-trimethylbenzoyl diphenylphosphine oxide, hexaallyl-m-phenyltricarboxamide, dimethyl azobenzene-4,4¢-dicarboxylate, N-phenyl-1,2,4-triazolidinedione, N-methyl-1,2,4-triazolidinedione, naphthalene, maleic acid ester, alkynyl alcohols with 4-9 carbon atoms and their silanized products, 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, polyvinylsiloxane, and polyvinylcyclosiloxane.

8. The photo / thermal curable moldable reactive liquid silicone resin emulsion composition according to claim 1, characterized in that: The carbon content of the hydrophobic silica particles is not less than 1.5%.

9. A method for preparing a flexible, highly porous foam material, comprising using the photo / thermal curable moldable reactive liquid silicone resin emulsion composition as described in claims 1-8, characterized in that... Includes the following steps: a. The reactive liquid M(D)Q silicone resin, water, nanofibers / particles or nanofibers / particles aqueous dispersion, and nonionic surfactant are emulsified and dispersed by high-speed mechanical emulsification to form a viscous two-phase aqueous emulsion. Curing agent, accelerator, and catalyst are added and rapidly mixed and dispersed to form a uniform emulsion. b. Pour the emulsion into a centrifuge or vacuum planetary mixer container, rotate it quickly to mix it evenly, and remove air bubbles under centrifugation or centrifugation with vacuum. c. Place the emulsion with the air bubbles removed under ultraviolet light, at room temperature for a long time, or in an oven or other container at a temperature not exceeding 100°C for pressureless curing. During molding, slowly inject the centrifugally degassed emulsion into the mold cavity under pressure and heat and pressurize it at a temperature not exceeding 100°C. Finally, take out the shaped foam product and dry it at low temperature to obtain a flexible high-pore foam material.

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