142 results about "Expandable microsphere" patented technology

Thermally expandable microspheres comprise a polymeric shell surrounding a hollow core, wherein the hollow core comprises a blowing agent, and the polymeric shell comprises isolated lignin.

The invention relates to the technical field of polymer microspheres, in particular to a thermal expansion microsphere and a preparation method and application thereof. The thermal expansion microsphere comprises a polymer shell and an inner core coated in the shell, the inner core comprises a foaming agent, and the thermal expansion microsphere is characterized in that the polymer shell is formed by polymerization reaction of a monofunctional monomer and a cross-linking agent under the initiation of an initiator; wherein the difference value between the 10-hour half-life period temperature of the initiator and the peak exothermic temperature of the cross-linking agent is 60-81 DEG C. By controlling the decomposition activity of the initiator and the reaction activity of the cross-linking agent to be matched in a specific temperature difference range, construction of a uniform cross-linked network between shell polymer chain segments is achieved, and the obtained thermal expansion microspheres have a wide expansion temperature range, good heat resistance, stable expansion behavior and high expansion rate.

The present invention relates to a one-component thermosetting epoxy resin composition, comprising an epoxy resin A having on average more than one epoxide group per molecule, a latent hardener for epoxy resins, at least one heat-expandable microsphere HEM1 with a mean particle size D (0.5) between 2.5 – 22.5 μm and at least one heat-expandable microsphere HEM2 with a mean particle size D (0.5) between 25 - 75 μm. The epoxy resin adhesive is notable for a reduced difference in expansion volumes at 140 °C vs. 200 °C for 30 min, especially after storage at elevated temperatures and humidity.

The invention discloses a preparation process of secondary foaming type water-based synthetic leather, and relates to the technical field of polymer foaming materials, the preparation process comprises the following steps: 1) epoxy modified thermal expansion microspheres; 2) side chain amino modified polyurethane; 3) preparing foaming slurry; 4) preparing the synthetic leather; firstly, thermal expansion microspheres are epoxidized, waterborne polyurethane is grafted with side chain amino protected by t-butyloxycarboryl, the crosslinking degree is improved through triphenylmethane triisocyanate, and then the waterborne polyurethane is mixed with the epoxy modified thermal expansion microspheres; after the first time of foaming by a mechanical means, in the step 4), t-butyloxycarboryl is heated and dissociated, CO2 gas is generated, active amino is released, the t-butyloxycarboryl is crosslinked with epoxy of the thermal expansion microspheres, meanwhile, the thermal expansion microspheres are expanded, and chemical foaming, namely second time of foaming, is achieved. Through cooperation of mechanical and chemical secondary foaming processes, the problems that traditional water-based leather is hard in hand feeling, bubbles are prone to collapse and the performance is single are solved, and the comprehensive performance is remarkably improved compared with the prior art.

The invention discloses a method for synthesizing thermal expansion microspheres by a controlled free radical polymerization method and a product thereof. The method comprises the following steps: mixing a nitrile monomer, an acrylate monomer, an initiator, a cross-linking agent, a foaming agent and an RAFT reagent to form an oil phase, emulsifying and dispersing the oil phase and a water phase containing inorganic salt and a dispersing agent, and carrying out polymerization reaction under the protection of nitrogen by adopting an optimized two-stage temperature control process (55 DEG C / 20h to 65 DEG C / 8h) to prepare the thermal expansion microsphere with the core-shell structure. 2-cyano-2-propylbenzo dithio acid ester is preferably used as an RAFT reagent, so that the compactness of a shell layer of the obtained microsphere polymer is remarkably improved, the expansion rate is higher, the temperature resistance is better, and the application range of the thermal expansion microsphere is widened.

The utility model relates to the technical field of thermal expansion microsphere production, and particularly discloses equipment for producing small-particle-size thermal expansion microspheres, which comprises a water phase homogenizing kettle, an oil phase homogenizing kettle, a water-oil phase homogenizing kettle, a centrifugal pump, a primary static mixer, a secondary static mixer, a polymerization kettle, a bypass assembly and a backflow assembly, the water phase homogenizing kettle and the oil phase homogenizing kettle are respectively connected with the water-oil phase homogenizing kettle through pipelines, the water-oil phase homogenizing kettle is connected with the centrifugal pump through a pipeline, the first-stage static mixer is connected with the centrifugal pump through a pipeline, the second-stage static mixer is connected with the first-stage static mixer through a pipeline, and the second-stage static mixer is connected with the second-stage static mixer through a pipeline. The polymerization kettle is connected with the second-stage static mixer through a pipeline, the bypass assembly and the backflow assembly are both connected with the pipeline between the centrifugal pump and the first-stage static mixer, and through the arrangement, the thermal expansion microspheres with better particle size distribution, better expansion performance and lower residual monomer amount can be obtained.

The invention relates to the technical field of molding powder coatings, in particular to low-temperature curing type electrostatic spraying molding powder and a production process thereof. The coating comprises modified polyester resin, thermal expansion microspheres, modified amide wax, a latent curing agent, a conductive composite filler, a pigment filler and an auxiliary agent, through a dual leveling system constructed by thermal expansion microspheres and modified amide wax, the resin viscosity can be reduced through microsphere expansion stress in the initial low-temperature melting stage, meanwhile, amide wax directionally forms a lubricating layer through hydrogen bonds, the surface tension is dynamically adjusted, and the problem of insufficient leveling or excessive migration caused by a fixed proportion of a traditional auxiliary is solved; the flatness of the coating is improved, and surface defects are eliminated; through a'resin-wax-curing agent 'ternary covalent network, an interpenetrating cross-linked structure is formed in the low-temperature curing process, the cohesion strength and weather resistance of the coating are enhanced, and the adaptability and long-term protection capability of the coating to a base material are improved through the interface interpenetrating effect of the thermal expansion microspheres and a resin matrix.

Methods, kits fand photothermal compositions for removing nail coatings are described. The nail coatings include a thermally responsive material, such as thermally expandable microspheres, and a nail product to be removed (e.g. nail polish, gel, dip, nail art, and / or artificial nail. Optionally, a bottom coating, such as lipoic acid, is in contact with the nail surface. The method includes (ii) applying a removal stimulus to a removal layer containing a photothermal additive to induce heat generation and cause at least partial expansion, shape change, and / or phase change of the thermally responsive material or partial detachment of the nail product. Optionally the method includes applying the photothermal nail composition on top of a nail coating prior to step (ii).

The present invention relates to tannin-based heat-expandable microspheres, and also to a process for their preparation. The heat-expandable microspheres comprise a thermoplastic shell surrounding a hollow core, wherein the hollow core comprises a blowing agent, and the thermoplastic shell comprises tannin.

Intumescent composition comprising an acid donor (A), a carbon donor (B), a binder polymer (C) and a blowing agent (D). The acid donor (A) is selected from the group consisting of ammonium polyphosphate, ammonium dihydrogen phosphate, ethylenediamine phosphate, ammonium pentaborate, guanylurea phosphate, diguanidine phosphate and mixtures thereof. The carbon donor (B) is selected from the group consisting of glucose, arabinose and other monosaccharides, lactose, maltose and other disaccharides, starch, cellulose, dextrin and other polysaccharides, sorbitol, erythritol, pentaerythritol, dipentaerythritol, mannitol and other polyhydric alcohols and mixtures thereof. The blowing agent is provided in the form of microsphere particles comprising a thermoplastic polymer shell encapsulating a propellant, which microsphere particles are expandable microspheres.

The present invention relates to a foamable polymer composition containing a polymer selected from the group consisting of polyolefins (PO),polyolefin elastomers (POE), polyolefin block co-polymers (OBC), ethylene vinyl acetate copolymers (EVA), EVA / PO copolymers, EVA / OBC copolymers, polyvinylchloride (PVC), polymers of styrene, natural and synthetic rubbers, polyamides, polyimides, and combinations thereof, a functionalized particulate bicarbonate, and thermally expandable microspheres, to methods for manufacturing a foamed polymer using such foamable polymer composition, and the use of said foamed polymers.

A coating composition, a preparation method therefor and use thereof are provided. The coating composition includes at least 60% heat-expandable microspheres having a wall thickness of less than or equal to 5 μm, a water-based thermoplastic resin, a water-based thermosetting resin, and a hot-melt filling resin. Thin-shell spheres can be quickly softened and ruptured within a short time in the heat-expansion process, and with the volatilization of an organic solvent, the coating composition cross-links with a resin matrix in the coating to form a cross-linked network structure, thus strengthening the gap support of the coating, and enabling the coating to achieve stepped expansion. After expansion, some polymer materials wrap an airbag and harden to form a stable hollow structure. Therefore, the expanded coating can be used for the fixation of high temperature-resistant parts, and can maintain adhesive stability when placed in a high-temperature environment (140-180° C.) for a long time.

The invention relates to a composition comprising at least one thermoplastic polyamide, wherein the average carbon content of the repeating units of said at least one thermoplastic polyamide is greater than or equal to 7; from 0.1 to 6.0 % by weight of expandable microspheres, based on the total weight of the composition; and optionally at least one additional thermoplastic polymer; wherein the composition has a melt flow index lower than or equal to 150 g / 10 min. The invention also relates to a method for preparing such a composition, to an expanded composition obtainable from such a composition and to a method for producing said expanded composition.

An electronic device manufacturing method comprising: a step for preparing a structure (100) including an adhesive film (10) that is provided with a base material layer (A) and an adhesive resin layer (C), and a workpiece (20) that is temporarily fixed to the adhesive resin layer (C); and a step for processing the workpiece (20) temporarily fixed to the adhesive resin layer (C), wherein the adhesive resin layer (C) includes thermally expandable microspheres, and the sphericity R of the thermally expandable microspheres as calculated by a prescribed formula is 0.93 or more.

To provide alternative thermoplastic expandable microspheres whose thermoplastic polymeric shell is at least partially derived from a sustainable source, a method for preparing the microspheres, and use of the microspheres.SOLUTION: There are provided thermally expandable microspheres comprising a polymeric shell surrounding a hollow core, wherein the hollow core comprises a blowing agent, and the polymeric shell comprises isolated lignin. The isolated lignin preferably comprises Kraft lignin such as acetylated Kraft lignin. A method for preparing thermally expandable microspheres comprising a polymeric shell surrounding a hollow core comprises the steps of (i) preparing a mixture comprising the isolated lignin and the blowing agent in a solvent, and (ii) spray-drying the mixture obtained in step (i) to obtain thermally expandable microspheres.SELECTED DRAWING: Figure 1

The application discloses a preparation method of homogeneous poly-methacrylimide wave-absorbing foam, and belongs to the technical field of functional foam materials. Thermally expandable microspheres are used as carriers, and iron metal framework structures with 5-hydroxy isophthalic acid as monomers are loaded on the surfaces of the carriers to obtain dispersed thermally expandable microspheres, which can be uniformly dispersed in the wave-absorbing foam, realize uniform foaming, and have uniform foaming effect and insignificant layering phenomenon. Meanwhile, core-shell toughening composite powders generated by a molten salt method are used as fillers of the wave-absorbing foam, so that the impact resistance and performance stability of the wave-absorbing foam in the foaming process are effectively ensured. The strong covalence of Ti-B bonds in the shell of the core-shell toughening composite powders makes the core-shell toughening composite powders have high conductivity, can absorb electromagnetic wave energy through a dielectric loss mechanism, and the boron nitride of the core can assist in forming multiple scattering interfaces and prolonging the electromagnetic wave propagation path, so that the wave-absorbing performance of the absorbent is increased.

The present invention relates to a lightweight waterproof roll and a preparation method thereof, comprising a first resin layer and a second resin layer, wherein heat-expandable microspheres are added to the first or second resin layer, the heat-expandable microspheres comprising a core material and an outer shell, the core material comprising a hydrocarbon compound and a liquid phosphorus-containing flame retardant, and the outer shell being an acrylic ester polymer obtained by polymerizing monomers; the polymerized monomers comprising a first polymerized monomer and a second polymerized monomer, the first polymerized monomer being an acrylic phosphate monomer, and the second polymerized monomer being at least one of a nitrile monomer, a carboxyl acrylic monomer, and a methacrylate monomer. The present invention provides a lightweight waterproof roll with a multi-layered resin layer structure, adding specific heat-expandable microspheres to one of the layers, and utilizing a multiple flame-retardant approach: the phosphorus-containing polymer outer shell of the heat-expandable microspheres and the phosphorus-containing flame retardant coating within the heat-expandable microspheres. This allows the waterproof roll to maintain its original flame retardancy while reducing its weight while maintaining mechanical properties.

The application relates to the field of functional fabric technology and discloses a one-way moisture absorption and sweat releasing double-sided warm-keeping fabric and application thereof. The one-way moisture absorption and sweat releasing double-sided warm-keeping fabric is formed by multi-dimensional weaving of hydrophilic fibers and hydrophobic fibers, the hydrophobic fibers are the inner layer, and the hydrophilic fibers are the surface layer; the hydrophilic fibers are polyester fibers, nylon fibers, spandex or bamboo fibers, and the hydrophobic fibers are heat-sensitive closed-cell foaming fibers. The heat-sensitive closed-cell foaming fibers are prepared by the following method: a glue agent is added into a solvent, dissolved at 70-90 DEG C, and stirred to obtain a resin solution; expandable microspheres, titanium dioxide and silica aerogel are added into the resin solution, and stirred to obtain foaming slurry; the matrix fibers are subjected to surface treatment, then the foaming slurry is coated, and then foaming treatment is carried out to obtain the heat-sensitive closed-cell foaming fibers. The fabric has the one-way moisture absorption and sweat releasing warm-keeping and heat insulation functions through the moisture gradient structure existing in the hydrophilic side and the hydrophobic side, has excellent warm-keeping and heat insulation and air and moisture permeation functions, and can be applied to the field of clothes.

This invention discloses a tearable shielded railway digital signal cable and its manufacturing method. The cable, from the inside out, comprises a cable core, an inner sheath, a shielding layer, and an outer sheath. The shielding layer includes: a functional composite layer, which is an integrated film containing a polyolefin matrix, conductive filler, and adhesive modifier; a structural carrier layer, which is a fiber-reinforced layer with a tensile strength greater than its transverse tensile strength along the cable length; and an outer sheath comprising an adhesive inner layer and a foamed outer layer. The adhesive inner layer contains dispersed thermally expandable microspheres; the structural carrier layer has openings. During the molding process of the outer sheath, the thermally expandable microspheres expand under heat and are squeezed into the openings of the structural carrier layer. After cooling, the adhesive inner layer and the structural carrier layer interlock. The cable of this invention possesses stable shielding layer peel performance, a uniform and lightweight foamed sheath structure, and reliable interlayer bonding, comprehensively improving construction convenience, electromagnetic shielding effectiveness, flexibility, and long-term reliability.

The present application provides a kind of thermal expansion microsphere with core-shell structure and its preparation method, the thermal expansion microsphere includes core and shell layer, the core includes foaming agent, the shell layer includes thermoplastic polymer, and the preparation monomer of the thermoplastic polymer includes conjugated diene monomer;By selecting thermoplastic polymer as the shell layer material of thermal expansion microsphere, and limiting the preparation monomer of the thermoplastic polymer includes conjugated diene monomer, the obtained thermal expansion microsphere with core-shell structure not only has lower initial expansion temperature, higher expansion degree, but also has excellent solvent resistance, and application field is more extensive.

Provided are methods of making a three-dimensional object that include (a) producing an intermediate object from a polymerizable liquid that includes heat expandable microspheres by additive manufacturing; (b) optionally, cleaning the intermediate object; and (c) moisture curing the intermediate object to form the three-dimensional object, said moisture curing performed before or after heating the object for a time and at a temperature sufficient to expand the microspheres. Objects produced by the methods are also provided.

This invention relates to a protective article comprising first and second walls. Each of the walls includes superimposed plies enclosing an expansion space therebetween, and an expandable composite disposed in the expansion space. The expandable composite includes a biodegradable matrix, and a plurality of cellulose-based expandable microspheres. The expandable microspheres are configured to cause the biodegradable matrix to expand upon activation of the expandable microspheres. The invention further relates to an expandable web comprising a first ply, second ply and an expandable composite deposited between the first ply and the second ply. The invention further relates to a method for making an expandable protective article.

Provided is a thermally expandable microsphere-containing water-dispersed adhesive composition which is capable of forming an adhesive that has good releasability by heating. The water-dispersed adhesive composition contains an acrylic polymer that serves as a base polymer, thermally expandable microspheres, and a crosslinking agent. With respect to the water-dispersed adhesive composition, the crosslinking agent contains at least one selected from the group consisting of an epoxy-based crosslinking agent, an oxazoline-based crosslinking agent, a carbodiimide-based crosslinking agent, an isocyanate-based crosslinking agent, a hydrazide-based crosslinking agent, and an aziridine-based crosslinking agent.

The low-hardness conductive silicone rubber is prepared from the following raw materials in parts by weight: 100 parts of methyl vinyl silicone rubber, 5-10 parts of fumed silica, 2-5 parts of hydroxyl silicone oil serving as a structure regulator, 1-2 parts of 2, 5-dimethyl-2, 5-bis (tert-butylperoxy) hexane serving as a vulcanizing agent, 0.1-1 part of TAIC (triallyl isocyanurate) serving as an assistant crosslinker, 1-10 parts of carbon nanotubes, 1-5 parts of MXene expandable microspheres and 1-6 parts of modified sodium bicarbonate. The invention also provides a preparation method of the low-hardness conductive silicone rubber. Through synergistic foaming of the ultrafine modified sodium bicarbonate and the MXene expandable microspheres, a uniform micropore and microsphere expansion hole interlocked foam structure is formed in the silicone rubber, the material is endowed with the lightweight characteristic by the structure, meanwhile, the hardness is remarkably reduced, the rebound resilience is improved, and the silicone rubber has compactness and flexibility due to the micropore filling effect; the material is an ideal material as a high-performance silicon rubber transfer printing rubber roller and a flexible sensing material.

An adhesive film (10) comprising a substrate layer (A) and an adhesive resin layer (C), wherein the adhesive resin layer (C) contains thermally expandable microspheres, and the number of pieces of foreign matter observed by a predetermined method is less than 10.

The present invention relates to a lightweight and aging-resistant cable sheath material based on expandable microspheres and a preparation method thereof, comprising the following raw materials in parts by weight: 63-75 parts of ethylene propylene diene monomer (EPDM), 22-32 parts of chlorinated polyethylene, 13-21 parts of expandable microspheres, 6-8 parts of processing aids, 5-7 parts of zinc oxide, 2-4 parts of vulcanizing agent, and 0.3-0.5 part of co-crosslinking agent; taking EPDM as the main body endows the material with excellent anti-aging performance; among them, chlorinated polyethylene can enhance the aging resistance of the material; among them, expandable microspheres can lighten the sheath material and improve the aging resistance of the material; one of the raw materials added to the expandable microspheres is modified boron nitride containing a variety of functional groups, which significantly enhances the mechanical properties and aging resistance of the material, and the performance is stable; the present invention has the advantages of good anti-aging performance, strong aging resistance, lightweight, and reduced agglomeration phenomenon.

The application belongs to the technical field of clothing and textile, and provides a warm-keeping clothing material and a preparation method thereof, which comprises the following steps: mixing polyimide powder, foaming powder, adhesive, cross-linking agent and solvent to prepare foaming slurry; the foaming powder is thermoplastic expandable microsphere foaming powder; the foaming slurry is applied to one surface of clothing fabric by printing or coating; after high-temperature baking, foaming printed fabric is obtained; the printed and coated surface of the foaming printed fabric is treated by three-dimensional embossing to form a certain depth of concave-convex structure, and the warm-keeping clothing material is obtained. The textile fabric prepared by the application has excellent temperature-locking and warm-keeping performance, thereby significantly improving the warm-keeping experience of the wearer of the clothing.

A method for manufacturing an electronic device, comprising the steps of: preparing a structure (100) including an adhesive film (10) having a base layer (A) and an adhesive resin layer (C), and a workpiece (20) temporarily fixed to the adhesive resin layer (C); and processing the workpiece (20) temporarily fixed to the adhesive resin layer (C), wherein the adhesive resin layer (C) includes thermally expandable microspheres, and the ratio (Ra2 / Ra1) of the arithmetic mean roughness Ra2 of the adhesive film (10) after a predetermined treatment by a predetermined method 2 to the arithmetic mean roughness Ra1 of the adhesive film (10) after a predetermined treatment by a predetermined method 1 is 0.40 or more.

The application relates to the field of flame-retardant technology, and particularly discloses a flame-retardant thermal expansion type foaming microsphere and a preparation method thereof. The thermal expansion type foaming microsphere has a core-shell structure and sequentially comprises a capsule core, an inner layer capsule wall and an outer layer flame-retardant capsule wall from inside to outside. Raw materials of the outer layer flame-retardant capsule wall include a phosphazene flame retardant, cobalt naphthenate and cyclohexanone peroxide. The flame-retardant thermal expansion type foaming microsphere provided by the application is coated with the phosphazene flame retardant which does not contain halogen, and the combination and coating rate of the phosphazene flame retardant and the foaming microsphere are improved through the cobalt naphthenate and the cyclohexanone peroxide, so that the flame-retardant efficiency and the flame-retardant stability of the foaming microsphere are significantly improved. In addition, the cobalt naphthenate and the cyclohexanone peroxide can promote the phosphazene flame retardant to degrade rapidly when a fire occurs, so that a dense carbon layer is rapidly formed on the surface of the foaming microsphere, and good flame-retardant and ablation-resistant effects are achieved. Therefore, the foaming microsphere has good foaming performance and flame-retardant performance, and has a wide application prospect.

The invention relates to the technical field of hollow silver-plated microspheres, in particular to a polymer hollow silver-plated microsphere and a preparation method thereof. At present, research on the polymer hollow silver-plated microspheres in the prior art is little, and a method for plating silver on the surfaces of the polymer hollow microspheres is not reported. In order to solve the technical problem, the invention provides the polymer hollow silver-plated microsphere which sequentially comprises a polymer hollow microsphere, a polythionocarbamate modified layer and a silver-plated layer from inside to outside. Polymer hollow microspheres obtained after thermal expansion microspheres are expanded serve as a matrix, polythionocarbamate modification is conducted on the surfaces of the polymer hollow microspheres through chemical modification, then chemical silver plating is conducted on the surfaces of polythionocarbamate modified layers, and finally the polymer hollow silver-plated microspheres are obtained. The silver plating layer obtained by the method is compact, continuous and uniform, and endows the polymer hollow microspheres with good conductivity and electromagnetic shielding performance.