78 results about "Melamine foam" patented technology

The application discloses a preparation method of three-dimensional hollow carbon spheres. The three-dimensional hollow carbon spheres are prepared by one-step pyrolysis method through the three-dimensional network structure of melamine foam and the compounding of MOFs materials. The method is simple in process, environment-friendly, low in cost and capable of industrial production. The three-dimensional hollow carbon spheres prepared by the method have uniform and good micro-morphology, the carbon spheres are hollow in the inside, each carbon sphere has four branches connected with other carbon spheres, and multiple carbon spheres are connected to form a three-dimensional network structure.

This utility model relates to the field of fire-resistant infill door technology, specifically: a reinforced fireproof infill door, comprising a door body, the door body being composed of an outer protective layer, a first fireproof and heat-insulating layer, a reinforcing support layer, a second fireproof and heat-insulating layer, a buffer and shock-absorbing layer, and an inner protective layer. The outer protective layer is a steel plate with a fireproof coating; the first fireproof and heat-insulating layer is an aerogel composite fireproof felt; the reinforcing support layer is a honeycomb stainless steel skeleton structure; the second fireproof and heat-insulating layer is an expanded perlite fireproof board; the buffer and shock-absorbing layer is melamine foam; and the inner protective layer is a fireproof decorative board. In this utility model, through the synergistic effect of the six layers, the performance of the door body is comprehensively improved from multiple aspects such as fireproofing, heat insulation, structural support, and buffer and shock absorption. It can effectively block the spread of flames and heat for a long time during a fire, ensuring the structural integrity of the door body and buying valuable time for safe evacuation and fire rescue.

The invention relates to the technical field of adsorption materials, in particular to ZIF-90-biochar-MF composite foam as well as a preparation method and application thereof. The preparation method comprises the following steps: by taking melamine foam as a matrix, carrying out coordination on a methanol solution of zinc nitrate hexahydrate and imidazole-2-formaldehyde to form a ZIF-90 precursor; the preparation method comprises the following steps: adding a ZIF-67 precursor into biochar to form a load liquid, then adding the load liquid into melamine foam, and then adding hexadecylamine for hydrophobic modification to obtain the ZIF-90-biochar (at) MF composite foam. According to the preparation method, cetylamine is used as a hydrophobic modifier, ZIF-90 is loaded on a melamine foam skeleton by an in-situ growth method, and charcoal is added, so that the prepared material can construct a micron-scale rough layer on the surface of a microporous membrane, the roughness of the surface of the MF skeleton is increased, and due to the fact that the surfaces of ZIF-90 and charcoal are rich in hydrophobic functional groups, the surface of the MF skeleton can be effectively improved. The surface hydrophobicity is improved, and the oil absorption performance of the composite material is improved.

The invention discloses a preparation method of an MF (at) NH2 (at) Ag SERS (Surface Enhanced Raman Scattering) sensor for detecting paraquat and diquat, belongs to the field of nano material synthesis and spectral analysis, and solves the problems that a traditional detection method is complicated in process and cannot detect pesticides and free radicals thereof at the same time, and a traditional SERS substrate is poor in enhancement effect and low in stability. The preparation method comprises the following steps: firstly segmenting melamine foam, cleaning and drying, soaking in hydrochloric acid, soaking in a polyethyleneimine aqueous solution to modify amino, drying, soaking in a silver nitrate solution for ultrasonic treatment, adding a sodium borohydride solution under an ice bath, stirring and reducing, and finally cleaning and drying to obtain the sensor. The sensor takes three-dimensional melamine foam as a support, silver nanoparticles are uniformly loaded on the surface of the three-dimensional melamine foam, paraquat, aquacide and free radicals thereof are enriched through electrostatic interaction based on a localized surface plasma resonance principle, and Raman signal enhancement is realized. The detection limit is 10 <-9 > mol / L, the signal stability and repeatability are excellent, the applicability to actual water sample detection is good, the detection of other pesticides can be expanded, and the method is suitable for on-site rapid trace detection.

The invention provides a solar-driven photo-thermal water-power cogeneration system and a preparation method thereof, according to the system, Fe3O4 and an MAX phase material are firstly combined through a unique material design, and then the combined material is coupled with super-hydrophobic SiO2, so that a super-hydrophobic MAX-Fe3O4 coated SiO2 photo-thermal composite material is prepared. The composite material is sprayed on the hot end of a thermoelectric module to efficiently absorb solar energy. And the cold end of the thermoelectric module is respectively connected with the foamy copper radiator and a water delivery channel made of a melamine sponge material. According to the design, on one hand, waste heat transferred to the cold end can be used for seawater evaporation; on the other hand, the temperature of the cold end can be further reduced through water evaporation, a continuous temperature difference is formed between the cold end and the hot end, and finally efficient solar-driven water and electricity cogeneration is achieved. By means of the design, multiple functions are integrated, the energy utilization efficiency is greatly improved, and a brand new thought is provided for research, development and application of a seawater desalination coupling electric energy production system.

The invention discloses a magnetic nanoparticle anchored heterogeneous carbon-based heat-conducting and wave-absorbing integrated material and a preparation method thereof, and belongs to the field of functional composites.The preparation method comprises the steps that melamine foam is acidized, and then acidized MF is soaked into a zinc salt, cobalt salt and 2-methylimidazole methanol solution; the obtained MF (at) ZnCo-ZIF is subjected to high-temperature calcination, and the heterogeneous carbon-based heat conduction and wave absorption integrated material anchored by the Co magnetic nanoparticles is obtained. The Co magnetic nanoparticle anchored heterogeneous carbon-based heat-conducting and wave-absorbing integrated material has the advantages of controllable morphology, high heat conductivity and strong wave-absorbing performance through the synergistic strengthening effect of the high-graphitization heterogeneous carbon material with high heat / conductivity and high dielectric loss and the Co magnetic nanoparticles with high magnetic conductivity and high magnetic loss; actual requirements of different scenes can be met, and a new thought is provided for research and development of a high-performance heat-conducting and wave-absorbing integrated material.

The utility model discloses a silencing device for a ventilation system of a heating ventilation air conditioner, and relates to the technical field of heating ventilation air conditioner equipment, the silencing device comprises a ventilation pipeline and a silencing assembly, the silencing assembly is used for eliminating noise generated in the ventilation process of the interior of the ventilation pipeline, and the silencing assembly comprises a silencing laminated plate and a side position closing plate; the side closing plate is fixedly connected to the side face of the silencing laminated plate, and a first high-frequency absorption layer, a low-frequency absorption layer and a second high-frequency absorption layer are arranged between the silencing laminated plate and the side closing plate. According to the utility model, the high-frequency absorption layer I, the low-frequency absorption layer and the high-frequency absorption layer II are arranged to form the structure shaped like the Chinese character'pin ', so that noise with different frequencies is subjected to targeted absorption treatment. The high-frequency absorption layer adopts melamine foam plastic to effectively capture high-frequency sound wave energy, and the low-frequency absorption layer and the sound absorption cotton layer have a synergistic effect to absorb low-and-medium-frequency noise, so that comprehensive treatment of broadband noise generated by the ventilation system is realized.

An acoustic blanket absorbs acoustic energy and reduces noise in a launch vehicle. The acoustic blanket may be overlaid on a wall of a payload fairing of the launch vehicle. Materials and construction of the acoustic blanket allow for a relatively thin and light sound barrier. The acoustic blanket may comprise vertically-lapped polyester that is overlaid with a lightweight melamine foam. This combination of materials creates an acoustic impedance mismatch between layers that leads to absorption of acoustic energy across a relatively broad range of frequency bands. The acoustic blanket has a particular heat seal pattern that helps absorb noise while allowing the acoustic blanket to be relatively soft and flexible, which is useful for attaching the acoustic blanket to a curved wall of a fairing or other launch vehicle shapes. The acoustic blanket utilizes micro-perforations on multiple sides to allow for movement of air / venting while maintaining the bulk materials inside.

The invention relates to the technical field of electric energy storage systems, and provides a wind power system cooperative operation method adopting a supercritical airfoil blade structure, which is used for solving the problem that the wind power acceptance capability of a power grid is influenced by blade vibration, and comprises the supercritical airfoil blade structure and a layered cooperative control system; the supercritical airfoil blade structure comprises a blade body composed of a blade root part, a blade body part and a blade tip part, a noise reduction piece is fixedly arranged on the rear edge of the blade body, a splicing groove is formed in the noise reduction piece, the rear edge of the noise reduction piece is in a continuous curve shape or a continuous broken line shape, and a groove is formed in the surface of the noise reduction piece. A melamine foam vibration absorption layer is arranged at the rear edge of the blade body in a clamped mode, and a vibration absorption groove is formed in the bottom of the splicing groove. A V-shaped opening for reducing the wind resistance area is formed in the blade tip part of the blade body; the layered cooperative control system comprises a dynamic power distribution module and an angular frequency error feedback synchronous control module.

The present application belongs to the technical field of sewage purification, and particularly relates to a foamed carbon-red mud composite material and a preparation method and application thereof. The preparation method of the foamed carbon-red mud composite material comprises the following steps: S1, red mud pretreatment; S2, synthesis of foamed carbon: mixing a sodium alginate solution, a calcium chloride solution and melamine foam, standing at room temperature to obtain a pretreatment mixture, and performing annealing treatment on the pretreatment mixture to obtain foamed carbon; and S3, preparation of the foamed carbon-red mud composite material: spraying modified red mud obtained by step S1 after being uniformly dispersed in water onto the surface of the foamed carbon. The foamed carbon-red mud composite material of the present application exhibits good light absorption in the range of 300-800 nm, and has a relatively high local temperature, and has better light absorption capacity and photothermal effect compared with foamed carbon, and can better purify sewage.

A layered, highly absorptive electromagnetic shielding composite material and its preparation method involve selectively etching the Al layer of Ti3AlC2 to obtain an MX solution. Fe3O4 and MX are then assembled into a composite material, FM. Melamine foam is then carbonized to obtain a carbonized foam, CF. FM is then assembled onto a CF skeleton via an impregnation method to form a composite foam, FM@CF. Finally, MX is deposited on the bottom of FM@CF via vacuum filtration to form the layered, highly absorptive electromagnetic shielding composite material, FM@CF / MX. The preparation process is simple and easy to operate. The layered structure achieves a "low reflection-high absorption-high reflection-reabsorption" strategy for electromagnetic waves, successfully achieving a combination of high electromagnetic absorption and high electromagnetic shielding efficiency, significantly reducing secondary electromagnetic contamination and helping to address the hazards of electromagnetic radiation. This material is widely used in aerospace, military equipment, microelectronic devices, consumer electronics, and other fields.

A cleaning roller (110) for a cleaner head (100) of a cleaning appliance (1). The cleaning roller (110) comprises: a roller core (111); a melamine foam layer (113) disposed around the roller core (111); and a permeable protective layer (115) disposed around the melamine foam layer (113). Also provided is a cleaner head (100) for a cleaning appliance (1), the cleaner head (100) comprising the cleaning roller (110). Also provided is a cleaning appliance (1) comprising the cleaning roller (110) or the cleaner head (100).

The invention discloses a preparation method of a D-mannitol-melamine foam composite solid-solid phase change material. The preparation method comprises the following steps: cutting melamine foam MF into small blocks; placing the melamine foam sample cut into blocks on a porcelain boat in a quartz tube of a tubular resistance furnace, carbonizing in a nitrogen atmosphere, and cooling to room temperature after carbonization is finished; adding the carbonized melamine foam CF block into molten D-mannitol DM, and carrying out vacuum impregnation in a vacuum drying oven; and taking out the impregnated sample, heating the sample on a heating plate, and removing redundant mannitol on the surface to obtain the D-mannitol-melamine foam. The prepared DM / CF composite material has excellent shape stability, leakage, loss or form out-of-control of the phase change material in the phase change process can be avoided, the safety and reliability of the material are guaranteed, and potential application prospects are provided for the fields of solar energy utilization, industrial waste heat recovery and the like.

The application discloses a kind of fiber reinforced aerogel fireproof heat insulation sheet and preparation method thereof.The preparation method includes the following steps:S1 dispersing fiber: dispersing agent, binder and fiber are added into solvent respectively, the mixture is dissociated at room temperature, and the fiber slurry is obtained after cooling to room temperature, ready for use;S2 mixed aerogel: aerogel powder and melamine foam are added into fiber slurry respectively, and the fiber reinforced aerogel slurry is obtained after stirring;S3 coating;S4 forming, to obtain fiber reinforced aerogel fireproof heat insulation sheet.The fiber reinforced aerogel fireproof heat insulation sheet prepared by the above method has low density, low thermal conductivity, low water absorption and high flame retardancy.

This invention discloses a reconfigurable absorbing metasurface based on heterogeneous absorbing units using a tenon-and-mortise interlocking structure, and its configuration method, belonging to the field of electromagnetic wave absorption and metasurface structure technology. The metasurface is formed by assembling multiple lightweight absorbing units through a tenon-and-mortise interlocking structure. The absorbing units use melamine foam, PMI foam, polyurethane foam, or aerogel porous framework materials as the matrix, and are loaded with absorbing components such as graphene, carbon nanotubes, MXene, ferrite particles, carbonyl iron particles, or conductive polymers. The tenon-and-mortise connection structure has multiple levels of insertion positions and limiting structures, allowing adjacent units to form different insertion states, thereby adjusting the unit spacing, air layer thickness, array period, and equivalent electromagnetic parameters, achieving reconfigurable control of the absorption frequency band and response characteristics. Furthermore, heterogeneous absorbing units with different geometries and absorption parameters can be optimized through parametric design and electromagnetic simulation to form planar or curved broadband absorbing structures. This invention combines the advantages of lightweight, modularity, detachability, surface adaptability, and wideband absorption, and can be applied to fields such as electromagnetic stealth, radar absorption, electromagnetic protection, and complex curved electronic equipment.

The invention discloses a FeNiO / carbon nanotube / carbon foam composite material as well as a preparation method and application thereof, and belongs to the technical field of lithium air battery materials. The melamine foam is placed in a mixed solution composed of nickel salt and iron salt, ultrasonic treatment is carried out for 10-100 min, standing is carried out for 1-12 h, drying is carried out, metal salt attached to the surface layer is removed, and FeNi / melamine foam is obtained; placing FeNi / melamine foam at the downstream of the crucible, placing a carbon source at the upstream of the crucible, and covering the crucible with a crucible cover; under the inert gas atmosphere, heating to 600-900 DEG C at the heating rate of 2-10 DEG C / min, keeping the temperature for 5-240 minutes, and naturally cooling to room temperature; and heating to 300-400 DEG C at a heating rate of 8-10 DEG C / min in an air atmosphere, preserving heat for 5-30 minutes, and cooling to room temperature to obtain the FeNiO / carbon nanotube / carbon foam composite material. According to the prepared FeNiO / carbon nanotube / carbon foam composite material, under the synergistic effect of multiple components, the charge-discharge specific capacity of a battery is greatly improved, and the service life of the battery is obviously prolonged.

The application discloses high-breathability sports shoes, comprising a vamp and a sole, wherein the sole comprises the following components in parts by weight: polyurethane 20-30 parts, polyoxyethylene ether 6-10 parts, butadiene styrene rubber 12-20 parts, modified polyvinylidene fluoride 5-10 parts, modified melamine foam 12-18 parts, zinc oxide 1-3 parts, vinyl trimethoxysilane 1-2 parts, diatomite 8-10 parts, calcium stearate 4-8 parts, vinyl silicone oil 5-8 parts and ethylenediaminetetraacetic acid 10-15 parts. The high-breathability sports shoes and the preparation method thereof improve the breathability of the material, and the material also has better mechanical strength.

This invention belongs to the field of polymer synthesis and application technology, and discloses a method for efficiently preparing melamine foam materials and their applications. This invention introduces unsaturated double bond groups into the melamine resin molecule design and employs a free radical-initiated chemical foaming technique to address the structural performance deficiencies of melamine foam materials, while simultaneously improving the overall material performance, thereby expanding its applications in high-performance adsorbent materials, wall insulation materials, and other fields. The melamine foam material efficiently prepared by the method of this invention has a brittleness mass loss rate of 2.0%, and the properties of the prepared foam material are as follows: apparent density 30-40 kg / m³. 3 The flexural strength is ≥200kPa, the compressive strength is ≥380kPa, and the volumetric water absorption rate is ≤1.0%. The brittle mass loss rate of the foam material of this invention is ≤2.0%, and it can be applied in the fields of wall insulation materials, adsorbent materials, etc.

The invention relates to a moisture power generation device and application thereof in degradation of VOCs, and belongs to the technical field of environmental protection. The moisture power generation device comprises a modified melamine foam electrolyte as well as an anode and a cathode which are arranged on two sides of the modified melamine foam electrolyte, the anode comprises carbon cloth and a thiazolyl conjugated polymer coated on the carbon cloth; the modified melamine foam electrolyte comprises melamine foam, and sodium alginate and phosphate group modified carbonized polymer points loaded on the melamine foam. The device does not need additional energy supply, can efficiently degrade pollutants under the conditions of normal temperature and normal pressure, and effectively breaks through the bottleneck problems of high reaction energy consumption, incomplete room-temperature degradation and the like in the existing VOCs treatment technology.

The invention discloses a PP-T / CMF-based composite phase change material with electromagnetic wave absorption performance, and the PP-T / CMF-based composite phase change material is prepared from the following raw materials: polyethylene glycol PEG 6000, poly-3, 4-ethylenedioxythiophene: polystyrene sulfonate PP, tetrabutyl titanate TBT and melamine foam MF; mF is used as a framework, and a T / MF foam matrix is obtained through hydrothermal reaction; calcining and carbonizing to obtain a T / CMF matrix; then, PP is subjected to vacuum impregnation and freeze drying, and a PP-T / CMF foam matrix is obtained; and finally, adsorbing PEG 6000 through vacuum. PEG 6000 is used as a heat storage medium; mF is a phase change material carrier and a supporting framework; pP is a conducting medium; tBT is used as a precursor; and ammonia water is used as a pH value regulator. The PP-T / CMF is of a three-dimensional network structure, and TiO2 nanoparticles are loaded on the surface of the PP-T / The preparation method comprises the following steps: 1, preparing T / CMF; 2, preparation of the PP-T / CMF; and 3, preparation of the PP-T / CMF / PEG. The material can be used as a phase-change material and a wave-absorbing material at the same time.

The present invention pertains to the field of functional materials technology, specifically relating to a preparation method, product, and application of modified melamine foam. The method described in this invention is simple, does not require special equipment or process conditions, and is easy to scale up for industrial production. The melamine foam produced by this method features a high open-cell rate and low density.

The invention relates to a preparation method of a ceramic fiber melamine composite flame-retardant thermal-insulation material and flame-retardant thermal-insulation cotton. The preparation method comprises the following steps: preheating ceramic fiber paper; preparing a binder, and coating one side surface of the ceramic fiber paper with the binder; the melamine foam is attached to the surface of one side of the binder layer, and the ceramic fiber paper layer and the melamine foam layer are attached together through the binder layer to form the composite flame-retardant thermal insulation material; and curing the composite flame-retardant thermal insulation material to complete the preparation. The inorganic glue is adopted as the binder layer to compound the ceramic fiber paper layer and the melamine foam layer, so that the composite flame-retardant thermal insulation material has the effects of low cost, high curing speed and outstanding thermal insulation effect, is simple to prepare, and is low in thickness and wider in application range under the same thermal insulation efficiency.

The invention relates to the technical field of adsorption materials, in particular to a charcoal modified melamine foam material as well as a preparation method and application thereof. The preparation method comprises the following steps: by taking melamine foam as a matrix, adding an alkali-activated charcoal dispersion liquid into the matrix, and loading alkali-activated charcoal through the matrix, so as to form a precursor; and sequentially adding hexadecane and dopamine hydrochloride into the precursor, and activating and modifying the alkali-activated biochar through hexadecane and dopamine hydrochloride by adopting an impregnation method to obtain the biochar modified melamine foam material. The prepared biochar modified melamine foam material has excellent super-hydrophobicity and super-lipophilicity, when the biochar modified melamine foam material is in contact with water, due to the fact that the surface of the biochar modified melamine foam material has a rough structure, and the surface energy is further reduced after cetane is soaked and covered, the biochar modified melamine foam material has excellent super-hydrophobicity and super-lipophilicity, and the biochar modified melamine foam material has excellent super-hydrophobicity and super-lipophilicity. The structures are difficult to wet by water and cannot enter the grid structures of the material, so that the hydrophobic and oleophylic effects are finally achieved.

The invention discloses a preparation method and application of bionic structure temperature adjusting foam, and belongs to the technical field of functional material and phase change energy storage crossing. According to the method, melamine foam serves as a matrix, phenolic resin is used for filling part of pores of foam, polyethylene glycol is adsorbed in vacuum for modification, and the formed temperature-adjusting foam has the characteristics of high enthalpy value and leakage prevention and has the functions of temperature adjustment, photo-thermal conversion, flame retardance and the like. The method is high in operability, simple in equipment, short in process and energy-saving, all component materials can be fully utilized, and waste is avoided; the obtained temperature-adjusting foam does not leak the phase-change material in a general state and can be recycled for multiple times; and the melting enthalpy and the crystallization enthalpy are relatively large, and an excellent temperature adjusting effect can be realized.

This utility model discloses a multi-layer conical cavity composite plywood, which, from top to bottom, consists of a surface layer, a flame-retardant layer, an upper microporous noise-reducing layer, an upper core layer, a middle layer, a lower core layer, a lower microporous noise-reducing layer, a moisture-proof layer, and a bottom layer. The surface layer is made of oak, the flame-retardant layer is made of antimony trioxide modified non-woven fabric, and the moisture-proof layer is made of aluminum foil. The upper and lower microporous noise-reducing layers have noise-reducing micropores, the upper and lower core layers have noise-reducing conical holes, the middle layer is embedded with rectangular melamine foam board, and the surface of the surface layer also has microgrooves. This plywood achieves multiple functions through a multi-layer structure. The various noise-reducing structures work together to reflect, refract, and absorb sounds of different frequencies multiple times, significantly reducing noise; the flame-retardant layer effectively improves fire resistance; and the aluminum foil moisture-proof layer can prevent moisture intrusion and extend service life. Its structural design is reasonable and can meet the needs of various places for flame retardancy, noise reduction, and moisture protection of the plywood.

A cleaning roller for a cleaner head of a cleaning appliance comprises a roller core 111, a melamine foam layer 113 disposed around the roller core and a permeable protective layer 115 disposed around

The invention relates to a preparation method of a photo-thermal-photocatalytic synergistic hydrogel evaporator with excellent salt resistance. The preparation method comprises the following steps: step 1, dissolving zirconium oxychloride octahydrate and 2-aminoterephthalic acid in N, N-dimethylformamide; 2, carrying out a hydrothermal reaction to obtain a reactant; step 3, taking out a reactant, washing with N, N-dimethylformamide and water, centrifuging, and freeze-drying, so as to obtain a UiO-66-NH2 metal organic framework; step 4, adding sodium alginate into water, and stirring under a constant-temperature magnetic stirring condition; step 5, sequentially adding a pyrrole monomer Py and a UiO-66-NH2 metal organic framework material into the uniform and transparent solution, and continuously mixing by using the constant-temperature magnetic stirrer to prepare homogeneous slurry; step 6, infiltrating melamine foam into the homogeneous slurry, and transferring the melamine foam into a CaCl2 solution; and 7, the sample obtained after calcium ion crosslinking treatment is placed in a FeCl3. 6H2O solution to be treated, and the photo-thermal-photocatalytic synergistic hydrogel evaporator is obtained. The preparation method has the characteristics of simple preparation process and large-area preparation.

The present invention belongs to the field of material processing technology, and specifically relates to a method for preparing a melamine foam component with adjustable and controllable density. The present invention foams a melamine formaldehyde resin solution in a microwave radiation field to form a lightweight melamine foam, which is then cooled and cut into rectangular plates by a cutting machine; the plates are immersed in an aqueous solution containing 0-5% silane or siloxane hydrolyzate or a slurry with a solid phase volume content of 0-25% to improve their surface properties; the foam absorbed with the aqueous solution is placed in a hot pressing mold with a large number of through-hole top covers; a hot press is used to hot press the plates, and the density and shape of the plates are adjusted by controlling the distance between the upper and lower metal hot pressing plates of the hot press; a vibration cutting machine or an engraving machine is used to perform shape processing on the hot-pressed plates to obtain the final melamine foam component with adjustable density, whose density ranges from 10 to 100 kg / m 3 , this method can effectively control the density uniformity of the product.

The invention provides a production method of melamine foam plastic with ultralow formaldehyde residue, which comprises the following steps: mixing melamine and paraformaldehyde in a molar ratio of 1: (1.5-1.9) with water, carrying out hydroxymethylation reaction, adding an amino-terminated hyperbranched polymer, and carrying out pre-polycondensation reaction, thereby obtaining the melamine foam plastic with ultralow formaldehyde residue. A hyperbranched modified melamine-formaldehyde resin prepolymerization solution is obtained; mixing the hyperbranched modified melamine-formaldehyde resin prepolymer with an emulsifier, a foaming agent, a curing agent, a graphite phase carbon nitride / reduced graphene oxide composite photocatalyst and potassium persulfate serving as a cocatalyst, and performing microwave foaming to obtain a primary foam product; and carrying out post-curing treatment, putting the treated melamine foam into a closed circulating treatment bin provided with a photocatalytic reactor, introducing steam, and carrying out decomposition and purification treatment and drying, so as to obtain the melamine foam plastic with ultralow formaldehyde residue. The invention solves the problems of high residual quantity of formaldehyde in the melamine foam plastic and complex and low-efficiency subsequent treatment process.

A collector comprising an absorption element 100 held on a fixed tray (Figure 5, 207) connected to a rod 200 having a channel 201 accommodating a test or indicator strip 300, wherein the tray is in fluid communication with an outlet of the channel. An elastic sheet may be fixed onto the tray in contact with, and optionally bonded with an adhesive to, the absorption element. One end of the strip may be in contact with the end of the absorption element through the outlet provided on the sheet. The adhesive may be applied so as not to seal the outlet. The tray may have a chamber with a bottom and a side wall wherein the opening is on the bottom of the chamber, one end of the absorption element is in the chamber and the fixing element surrounds the absorption element. The elastic element may be provided in two parts and may be made of annular rubber or latex. The absorption element may comprise polyester, a sponge, cotton and a filter paper, or a polypropylene sponge, a polyvinyl alcohol sponge and a polypropylene or melamine foam, and may be rigid when dry but deform when wet, or soft and compressible when dry.