CN110685183A - Aldehyde-removing non-woven fabric and preparation method and application thereof - Google Patents
Aldehyde-removing non-woven fabric and preparation method and application thereof Download PDFInfo
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- CN110685183A CN110685183A CN201910940667.2A CN201910940667A CN110685183A CN 110685183 A CN110685183 A CN 110685183A CN 201910940667 A CN201910940667 A CN 201910940667A CN 110685183 A CN110685183 A CN 110685183A
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- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H15/00—Pulp or paper, comprising fibres or web-forming material characterised by features other than their chemical constitution
- D21H15/02—Pulp or paper, comprising fibres or web-forming material characterised by features other than their chemical constitution characterised by configuration
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D39/00—Filtering material for liquid or gaseous fluids
- B01D39/08—Filter cloth, i.e. woven, knitted or interlaced material
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/46—Removing components of defined structure
- B01D53/72—Organic compounds not provided for in groups B01D53/48 - B01D53/70, e.g. hydrocarbons
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- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H13/00—Pulp or paper, comprising synthetic cellulose or non-cellulose fibres or web-forming material
- D21H13/10—Organic non-cellulose fibres
- D21H13/12—Organic non-cellulose fibres from macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
- D21H13/16—Polyalkenylalcohols; Polyalkenylethers; Polyalkenylesters
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- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H13/00—Pulp or paper, comprising synthetic cellulose or non-cellulose fibres or web-forming material
- D21H13/10—Organic non-cellulose fibres
- D21H13/20—Organic non-cellulose fibres from macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
- D21H13/24—Polyesters
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- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H19/00—Coated paper; Coating material
- D21H19/36—Coatings with pigments
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- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H19/00—Coated paper; Coating material
- D21H19/36—Coatings with pigments
- D21H19/44—Coatings with pigments characterised by the other ingredients, e.g. the binder or dispersing agent
- D21H19/56—Macromolecular organic compounds or oligomers thereof obtained by reactions only involving carbon-to-carbon unsaturated bonds
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- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H19/00—Coated paper; Coating material
- D21H19/36—Coatings with pigments
- D21H19/44—Coatings with pigments characterised by the other ingredients, e.g. the binder or dispersing agent
- D21H19/64—Inorganic compounds
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- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
- D21H21/50—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by form
- D21H21/52—Additives of definite length or shape
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- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H23/00—Processes or apparatus for adding material to the pulp or to the paper
- D21H23/02—Processes or apparatus for adding material to the pulp or to the paper characterised by the manner in which substances are added
- D21H23/22—Addition to the formed paper
- D21H23/50—Spraying or projecting
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- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H25/00—After-treatment of paper not provided for in groups D21H17/00 - D21H23/00
- D21H25/04—Physical treatment, e.g. heating, irradiating
- D21H25/06—Physical treatment, e.g. heating, irradiating of impregnated or coated paper
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- D—TEXTILES; PAPER
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- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H27/00—Special paper not otherwise provided for, e.g. made by multi-step processes
- D21H27/08—Filter paper
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Abstract
The invention discloses an aldehyde-removing non-woven fabric and a preparation method and application thereof, wherein the aldehyde-removing non-woven fabric comprises coarse fibers, fine fibers, acrylic resin and a carrier, wherein the fineness of the coarse fibers is 5.0-8.0dtex, the fineness of the fine fibers is 1.0-2.0dtex, and the carrier contains inorganic porous particles. The aldehyde-removing non-woven fabric has the characteristics of low resistance, high aldehyde-removing efficiency and high stiffness, is particularly suitable for the field of air purification after being compounded with electrostatic non-woven fabric and the field of household and office fresh air filters with high requirements on the rigidity and resistance of the filter fabric at high air volume, and is used for the framework supporting layer of three-layer compound non-woven fabric clamped by active carbon and/or porous carriers.
Description
Technical Field
The invention belongs to the technical field of filter materials, and particularly relates to an aldehyde-removing non-woven fabric, and a preparation method and application thereof.
Background
At present, many new houses of families and office houses can have various materials when being decorated, more materials are applied to indoor space, the indoor space can be enriched, and the texture is stronger. However, some interior materials contain some formaldehyde content, i.e., after the new house is finished, the air of the new house is perceived to have an irritating odor. And at present, many families choose to place air purifiers in the indoor space to adsorb and filter the formaldehyde in the indoor space. At present, a plurality of aldehyde removing filter elements on the market are provided, such as honeycomb net type (medicament catalysis or reaction type), active carbon clamping type (medicament catalysis or reaction type) and photocatalytic type. However, in any of these methods, there is a problem that the initial efficiency of formaldehyde is low. The reason is that the honeycomb net type or the activated carbon holding type has large particles and a small specific surface area. The coarse particles not only increase the air intake resistance of the filter element, but also have less contact surface with formaldehyde gas, directly cause the reduction of formaldehyde removal effect (formaldehyde adsorption clean air quantity, referred to as FCADR for short), bring about the problem of the reduction of particulate matter removal effect (particulate matter clean air quantity, referred to as PCADR for short), thereby influencing the use effect. Therefore, on the basis of not increasing the resistance of the filter element, the problem in the industry is to increase the formaldehyde FCADR while maintaining the particle PCADR.
In addition, Chinese patent CN102794052A discloses an air filter material and application thereof, wherein the aldehyde-removing non-woven fabric material is obtained by mixing and spraying 5-150 micron activated carbon particles and an adhesive on a non-woven fabric (wherein the weight of the activated carbon particles is 10-100 g/m 2). In this patent technology, not only the fiber ratio of the nonwoven fabric is not further described, but also the pore volume of the porous material of activated carbon, and the specification and properties of the porous carrier such as D50 are not described in detail. Because of the fiber thickness, the arrangement of thick and thin fibers, the diameter of the porous carrier particles and the like, the sedimentation, the mangle amount, the dry weight attachment amount, the aldehyde removal efficiency and the like during the liquid preparation and processing can be influenced. According to the patented technology (CN102794052A), the amount of attached activated carbon and the effect of removing aldehydes were greatly reduced.
Disclosure of Invention
The invention aims to solve the technical problems and provides an aldehyde-removing non-woven fabric, a preparation method and application thereof.
The formaldehyde-removing non-woven fabric comprises coarse fibers, fine fibers, a carrier and acrylic resin, wherein the fineness of the coarse fibers is 5.0-8.0dtex, and the coarse fibers account for 25-45% of the total weight; the fineness of the fine fibers is 1.0-2.0dtex, and the fine fibers account for 5-20% of the total weight; the carrier contains inorganic porous fine particles, the D50 of the inorganic porous fine particles is 5-30 micrometers, and the inorganic porous fine particles account for 3-30% of the total weight; the glass transition temperature of the acrylic resin is 30-70 ℃, and the acrylic resin accounts for 25-40% of the total weight.
Furthermore, the carrier contains inorganic porous coarse particles, and the D50 of the inorganic porous coarse particles is 40-80 microns and is 0.5-3 wt%.
Further, the specific surface area of the inorganic porous fine particles and the inorganic porous coarse particles is 300-600 m2/g, and the pore diameters of the inorganic porous fine particles and the inorganic porous coarse particles are less than 20nm and account for more than 80% of the total pore volume.
Further, the carrier also contains one of macromolecule dendritic polymer, macromolecule dendritic modified polymer or a mixture of macromolecule dendritic polymer and macromolecule dendritic modified polymer, and the content of the macromolecule dendritic modified polymer is 5-10% of the total weight.
Further, the inorganic porous fine particles contain silica dendritic modified polymers, and the content of the silica dendritic modified polymers accounts for 50% -80% of the total weight of the inorganic porous coarse and fine particles.
Furthermore, 0.3-1.0 g/m2 antibacterial agent is added into the aldehyde-removed non-woven fabric.
The preparation method of the aldehyde-removing non-woven fabric comprises the following steps:
step (1): uniformly dispersing the coarse fibers and the fine fibers to prepare fiber slurry, mixing the fiber slurry with white water to form fiber slurry, forming by an inclined net, and finally forming a fiber net by vacuum water absorption;
step (2): coating acrylic resin on the surface of a fiber net, then drying in an oven at the speed of 15-40 m/min, reinforcing and forming to obtain a non-woven fabric;
and (3): the mixture of the porous carrier particles, acrylic resin and a surfactant is attached to the non-woven fabric through post-processing technologies such as spraying, liquid tank padding or foam padding, and the aldehyde-removing non-woven fabric is prepared after drying.
Furthermore, a spraying process is preferred, and when the standard flow of the spraying holes is 0.3MPa, the flow is 0.5-2.0L/min.
Further, in the acrylic resin coating process of step (2) or the post-processing process of step (3), a pigment or a disperse dye may be added for coloring.
The use of the above-described aldehyde-removing nonwoven fabric in an air filtration device or ventilation system.
The aldehyde-removing non-woven fabric has the characteristics of high carrier adhesion, low aldehyde-removing non-woven fabric resistance and high aldehyde-removing FCADR. Through the selection and design such as the fiber thickness, the thick and thin fiber collocation, the diameter size of porous carrier particulate matter when adding man-hour, solved settlement, the mangle gauge height of adding man-hour to guaranteed that porous carrier particulate matter adheres to the height, the pore is not blockked up by acrylic resin, removes aldehyde effect maximize.
Drawings
Fig. 1 is a schematic structural view of a composite nonwoven fabric of the present invention.
Detailed Description
The present invention will be further described with reference to the following specific examples.
As shown in fig. 1, the nonwoven fabric comprises coarse fibers, fine fibers, acrylic resin and porous carrier particles, and the coarse fibers and the fine fibers are mixed for use, so that the effects of coarse fibers, high stiffness, high air permeability maintenance, and low resistance can be achieved; meanwhile, the low resistance also increases the FCADR of the material, because at low resistance, the number of times of ventilation is increased, thereby increasing the number of times of contact between the gaseous pollutants and the aldehyde-removing non-woven fabric, and further increasing the FACDR; fine fibers with more specific surface area can be attached with more carriers, including inorganic porous particles; the material of the fiber is not limited to polyester fiber, vinylon fiber, nylon fiber, viscose fiber, modified fiber, and the like; preferably, the coarse polyester fiber and the fine vinylon fiber are matched for use; the acrylic resin is used as an adhesive to ensure that particularly inorganic porous particles cannot fall off due to compounding and folding; wherein the fineness of the coarse fibers is 5.0-8.0dtex, and the coarse fibers account for 25-45% of the total weight; the fineness of the fine fibers is 1.0-2.0dtex, and the fine fibers account for 5-20% of the total weight; the carrier contains inorganic porous fine particles, the D50 of the inorganic porous fine particles is 5-30 micrometers, and the inorganic porous fine particles account for 3-30% of the total weight; the glass transition temperature of the acrylic resin is 30-70 ℃, and the acrylic resin accounts for 25-40% of the total weight; the fineness of the coarse fiber is higher than 8dtex, so that the fiber is unevenly dispersed in water, the filamentation of the fiber is easy to finish, and the fineness is lower than 5dtex, so that the aim of coarse fiber-high stiffness cannot be achieved; the proportion can reach the supporting function when the proportion is maintained to be minimum 25 percent, the normal use and the high air volume of the filter element are achieved, the fiber quantity is reduced when the proportion is higher than 40 percent, and the attaching quantity of the carrier, including the porous carrier particles, is lower because the specific surface area is less, and even is lower than 5g/m 2; the fineness of the fine fiber is 1.0-2.0dtex, of course, the invention is not objected to lower than 1.0dtex due to the fiber manufacturing process, as long as the dispersibility and the processability are simultaneously satisfied during production, such as 0.8dtex and 0.6dtex superfine fibers with good hydrophilicity and uniformity; above 2.0dtex, the specific surface area of the fiber is reduced, the attachment amount of the carrier, including porous carrier particles, is reduced, and the aldehyde removal effect is greatly reduced; 5% -20% is recommended for the proportion of the fine fibers, the existence of the fine fibers can not only increase the specific surface area and increase the attachment amount of the porous carrier particles, but also improve the uniformity of the cloth cover; meanwhile, the amount of fine fibers is more than 20 percent, so that the attachment amount of the porous carrier particles can be improved, but the corresponding amount of coarse fibers is reduced, the stiffness and the air permeability of the non-woven fabric can be greatly reduced, and after the non-woven fabric is processed into a filter element (a flat plate or a cylinder), the filter paper can deform under high air flow, the resistance can be improved, and the noise is increased; of course, the present invention is not directed to the increase of fine fibers or the total fine fibers, regardless of the negative effects of the decrease in stiffness and air permeability, and the fibers of the present invention, whether coarse fibers or fine fibers, are all fibers, but glass fibers, nylon fibers, vinylon fibers, and the like can be used as long as they can improve the stiffness of the nonwoven fabric and the amount of the porous carrier particles adhered thereto without affecting the production process.
The proportion of the fine fiber is preferably 5-10%, and in the range, the proportion of the coarse fiber and the fine fiber is comprehensively considered, so that the best effects of stiffness, porous particulate matter attachment amount and air permeability are achieved, and the best aldehyde removal filtering effect is brought.
The carrier comprises porous carrier particles, and the purpose of the carrier is to provide more contact area and capacity for functional agents which generate chemical reaction with formaldehyde, or catalysts which accelerate the decomposition of formaldehyde and self-generated formaldehyde due to light, heat, ultraviolet rays and the like; although the functional medicament is also good, the photocatalyst and the cold catalyst can be directly attached to the surface of the non-woven fabric, compared with the use of a carrier, the attachment amount is different by several times, even dozens of or hundreds of times; the carrier can be natural or artificial, can be a stable phase which is dissolved or suspended in water, and can also be inorganic particles; however, since the nonwoven fabric needs to be folded at a later stage, and the nonwoven fabric needs to be contacted with a folding knife, the aldehyde-removing nonwoven fabric is required to have the requirements of non-sticking, no deformation when being heated, and difficult bringing out when the folding knife is pulled out from the aldehyde-removing nonwoven fabric, the invention requires that the nonwoven fabric contains inorganic porous fine particles, is convenient to process, and has the D50 (median diameter) of 5-30 microns and the weight percentage of 3-30%. Preferably 7 to 15 microns. For the particles D50, the particle size is less than 5 microns, the particles are too fine, the particles are easy to fly during production, and meanwhile, when the particles are adhered to the surface of the fiber, the particles are easily covered by acrylic resin, most of pores are blocked, and the aldehyde removal effect is reduced; moreover, the adsorption rate is high at the initial stage due to the excessive fineness/excessive amount of the particulate matter, which leads to a decrease in the adsorption life (durability); in particular, the wide presence of fine particles is not conducive to the folding process; the particle size is larger than 30 microns, the particle size is relatively overlarge, the adhesion is easy to reduce, and sedimentation and poor aldehyde removal are easy to occur during production; moreover, the particles are large, the adhesion amount to fine fibers is reduced, and the aldehyde removal effect is reduced; particularly, the particles are relatively too large, and fall off easily during folding and processing on the formaldehyde-removing non-woven fabric, so that the formaldehyde-removing performance is reduced; d50 is preferably 7-15 μm, and the particle size range can be optimized for the adhesion of non-woven fabric, powder scattering during production, dispersion in water, and aldehyde removal effect; meanwhile, in order to increase the aldehyde removal effect and prolong the service life, the invention recommends that the mixture of the coarse porous carrier particles with the D50 of 05-3 percent and the particle size of 40-80 microns is used; the existence of coarse particles of 40-80 microns can greatly delay the direct reaction with formaldehyde at the initial stage, delay the reaction time and prolong the service life; meanwhile, the coarse and fine mixed porous carrier particles are mixed for use, so that direct coverage of acrylic resin can be avoided, and the actual utilization rate of the formaldehyde removal substance is improved.
For acrylic resin, the glass transition temperature is 25-55 ℃, the weight percentage is 25-40%, the glass transition temperature is preferably 35-45 ℃, the too low glass transition temperature reduces the stiffness and exceeds 55 ℃, the adhesive force between fibers is reduced, the tensile strength is low, and the post-processing is not easy; for the content of the acrylic resin, the minimum amount necessary for serving as a support material is maintained, and meanwhile, the phenomena of powder falling and the like of inorganic porous particles are avoided; of course, the proportion of more than 40% will block the pores of the porous carrier, resulting in a large reduction in the aldehyde removal effect.
The porous carrier particles comprise coarse particles and fine particles, the specific surface area is 300-600 m2/g, and the actual attachment amount of the aldehyde-removing medicament can be increased to the maximum extent; if the concentration is higher than 600m2/g, the porous carrier particles are easily extruded by a rolling rod, a tension rod and the like during later use, and the porous carrier particles are crushed, so that the defects of powder falling and the like of the cloth cover are caused; meanwhile, the problem of easy adsorption and separation of gas molecules or hydrophilic micromolecules and secondary odor generation due to the excessively high specific surface area; the adhesive amount of the aldehyde removing agent is greatly reduced when the adhesive amount is less than 300m 2/g; the pores have a size of 20nm or less which accounts for 80% or more of the total pore volume; the fine and numerous pores can adsorb more formaldehyde gas, and simultaneously avoid the risk of reduction of the filtering effect caused by secondary escape; the pore volume is 1.0-9.0 ml/g, and in the range, aldehyde small molecules, particularly formaldehyde molecules, can easily enter the inner wall of the pores and have a penetrating effect, and meanwhile, large molecules such as TVOC (total volatile organic compound) are difficult to enter; therefore, the formaldehyde remover is particularly suitable for being in direct contact with formaldehyde removing agents, and the formaldehyde removing efficiency and the service life are improved.
In order to avoid the sedimentation of the porous carrier particles, part of the porous carrier particles can be subjected to hydrophilic modification to achieve the aim of difficult sedimentation in water; meanwhile, it is also recommended that a polyethylene glycol surfactant is further used to improve the dispersibility of the particles and the medicament and avoid the particle sedimentation during production; the proportion is 0.1-1.0%, and is determined according to the production process. More than 1.0 percent, or too many hydrophilic modified porous carrier particles can increase the hygroscopicity, so that the stiffness of the non-woven fabric is increased, the porous carrier particles absorb moisture, and mildew is generated, so that a series of problems such as peculiar smell and the like can be caused; for the present invention, as long as the later use and the generation of problems are not affected, the mixed use of the common porous carrier particles and the hydrophilic modified porous carrier particles, even the addition of a part of the surfactant and the like, is within the technical scope of the present patent.
The carrier contains a macromolecular dendritic polymer and/or a macromolecular dendritic modified polymer, and the content of the macromolecular dendritic modified polymer is 5-10%. The high molecular dendritic polymer has a regular and controllable branched structure, a large number of functional groups on the surface of the high molecular dendritic polymer can be covalently connected with an aldehyde removal medicament, and hollow hydrophobic cavities in the spherical shape can also be connected with functional aldehyde removal groups through hydrogen bonds, electrostatic action, van der waals force and the like, so that formaldehyde molecules can be adsorbed/reacted directionally, slowly and more efficiently; the presence of a dendrimer in general has a problem of hydrophilicity due to covalent bonding with an aldehyde-removing group or the like; although a part of the inorganic porous carrier particles is selectively mixed in the present invention, an excessive amount, particularly more than 10%, causes problems such as folding, sticking and folding of a knife and an equipment part during assembly, and also causes problems such as moisture absorption and generation of an offensive odor over a long period of time; of course, below 5%, the effect of removing aldehydes is greatly impaired.
Further, in the porous particles, the proportion of the silica dendritic modified polymer accounts for 50-80% of the total weight percentage of the total porous particles; in order to improve the hydrophilic effect of the inorganic porous particles, the porous particles can be subjected to dendritic modification; the invention recommends the silicon dioxide dendritic modified polymer, which not only can functionalize the surface of silicon dioxide powder, but also can obviously improve the dispersibility and compatibility of the silicon dioxide in water; meanwhile, the attachment amount of the aldehyde removing agent can be greatly increased by virtue of the characteristics of the dendritic modified polymer; the use amount of 50 to 80 percent can achieve the best effect on the aspects of aldehyde removal effect, processability and the like.
The non-woven fabric is also added with 0.3-1.0 g/m2The antibacterial agent of (1); for the convenience of underwater processing (dispersion in water, processing such as spraying, sprinkling, dipping, etc.), it is necessary to perform partial hydrophilic processing or to add a surfactant to the inorganic porous particulate matter. But also brings the problems of moisture absorption and even generation of peculiar smell due to breeding of bacteria and mould; in order to avoid the problem, the effect of the formaldehyde removing medicament is not easily influenced, and the optimal antibacterial effect can be achieved by adding a small amount of the formaldehyde removing medicament, the invention recommends nano metal particles of silver, copper, zinc and the like or compounds thereof.
The preparation method of the formaldehyde-removing non-woven fabric comprises the steps of uniformly dispersing coarse fibers and fine fibers to prepare fiber slurry, mixing the fiber slurry with white water to obtain fiber slurry with a concentration, forming the fiber slurry through an inclined net, and finally forming a fiber net through vacuum water absorption; then coating acrylic resin on the surface of the fiber net, then drying in an oven at the speed of 15-40 m/min, reinforcing and forming, and finally preparing a non-woven fabric; finally, the mixture of the carrier, the aldehyde-removing medicament, the acrylic resin, the surfactant and the like is applied to the surface and the inside of the non-woven fabric through post-processing technologies such as spraying, liquid tank padding or foam padding, and the like, and the aldehyde-removing non-woven fabric is prepared after drying; according to the method, preferably, coarse fibers and fine fibers are uniformly dispersed and are separately prepared into fiber slurry, then the fiber slurry is respectively mixed with white water to form fiber slurry, the fiber slurry is formed by inclined net forming, coarse (upper)/fine (lower) fiber nets are overlapped and formed, then the fiber nets are formed by vacuum water absorption, finally acrylic resin is coated on the surfaces of the fiber nets, and the fiber nets are dried in an oven and are reinforced and formed to finally prepare the non-woven fabric; compared with the common non-woven fabric mixed with thick and thin fibers on the market, the non-woven fabric with the thick/thin fibers layered up and down achieves the characteristic of a gradient structure; the filter screen not only has the optimized air-permeable structure of the coarse fiber layer-coarse particles and the fine fiber layer-fine particles when a carrier is added in the next process, but also has the advantage of gradient filtration of the coarse/fine particles when being used after being compounded with electret melt-blown nonwoven fabric into the filter screen, thereby prolonging the service life of the filter material; the structure formed by overlapping the fine (upper)/coarse (lower) fiber webs is not beneficial to the permeation of acrylic resin; because the acrylic resin is coated on the surface of the fiber net, the acrylic resin passes through the upper fiber layer, then the lower fiber layer and finally the rubber groove/barrel through the vacuum negative pressure pipeline by means of the vacuum negative pressure from top to bottom; the upper fibrous layer, if of fine fiber construction, is clearly detrimental to the permeability of the acrylic resin.
Preferably, a spraying process is adopted; for the selection of the size of the spray hole, the spray hole with the flow rate of 05-20. L/min is adopted when the standard flow rate is 0.3 MPa; the spray holes larger than 2.0L/min are too large, the uniformity of sprayed liquid is poor, and the non-uniform high-low formaldehyde removal efficiency of the non-woven fabric surface is easily caused; less than 0.5L/min, too small pores, easy friction of the porous carrier particles with the porous carrier particles, less ejection amount, reduced adhesion of the porous carrier particles on the surface of the non-woven fabric, and reduced aldehyde removal effect; the material of the orifice may be SUS stainless steel or ceramic.
Meanwhile, in the acrylic resin coating process in the step (2) or the post-processing process in the step (3), a pigment or a disperse dye can be added for coloring; the required colors of blue, purple, black and the like can be prepared by mixing pigments or dyes with different colors.
The aldehyde-removing nonwoven fabric of the invention is used in an air filtering device or a ventilation system; in particular for reducing the concentration of formaldehyde gas in a relatively confined space. Can be used for adsorption filtration and can also be matched with other forms or types of adsorption materials for use.
The test method adopted by the embodiment of the invention is as follows:
1. resistance force: cutting the non-woven fabric into a fixed size, and standing for 24 hours for pretreatment under the conditions of constant temperature and constant humidity (23 ℃, humidity of 50% RH); then placing the filter medium on a machine with a filtering area of 100 square centimeters, adjusting the wind speed to 5.3cm/sec, and measuring the resistance of the filter medium after the filter medium is stabilized; (for too low a nonwoven resistance, 5 overlap tests can be performed, averaged) units: pa.
2. Aldehyde removal efficiency: cutting the non-woven fabric into a fixed size, and standing for 24 hours for pretreatment under the conditions of constant temperature and constant humidity (23 ℃, humidity of 50% RH); then, the filter cloth is placed in a 3-cubic meter bin and is fixed on a die with the filtering area of 100 square centimeters; generating formaldehyde gas to stabilize the concentration of formaldehyde in the bin at 1.0 +/-0.2 mg/m3Left and right, the specific concentration is read as V1; continuously passing the gas in the bin through the nonwoven fabric sample at the wind speed of 5.3cm/sec, and testing the formaldehyde gas concentration V2 in the bin after 35 minutes to obtain the formaldehyde removal efficiency of (V1-V2)/V1 x 100%; unit: % of the total weight of the composition.
3. Rigidity: cutting a nonwoven fabric into a fixed size of 3.5 × 1.0 inch according to JIS 1096, and standing the cut nonwoven fabric for 24 hours under constant temperature and humidity conditions (23 ℃, humidity 50% RH); the warp direction rigidity of the nonwoven fabric was measured using a grignard type rigidity (stiffness) tester; unit: and (5) mg.
4. FCADR: folding and injecting glue to the non-woven fabric to manufacture the filter element of the air purifier, wherein the size of the filter element is 361mm by 276mm by 38 mm; put into a Philips air purifier AC1212In the test, the formaldehyde adsorption clean air quantity, called (filter element) FCADR (m) is tested according to the GB18801-2015 standard3/h)。
5. Particle size (median diameter D50): the particle size distribution of the inorganic porous particles was tested using a laser particle sizer, model Winner 2000Z; the median diameter is obtained. The number of samples was 3 and the average was taken.
6. Pore diameter: the pore size distribution of the inorganic porous particulate matter was tested using a BJT method suction-desorption pore volume pore size distributor, model BK 200A. Obtaining the aperture of the meso-position; the number of samples was 3 and the average was taken.
Example 1
Porous particulate matter, porous particulate matter using silica, specific surface area 520m2G, pore volume 3.2 ml/g.
The polyester fiber with the fineness of 8.0dtex and 1.0dtex and acrylic resin (Tg is 47 ℃, the same below) are processed by a wet papermaking process to obtain the weight of 60g/m2Support layer nonwoven fabric of (1). Mixing and stirring a common high-molecular dendritic polymer carrier, a silica porous particulate carrier with 20 microns of D50, an aldehyde-removing functional medicament and the like (succinic dihydrazide is used as an experimental medicament in the embodiment, but not limited to other aldehyde-removing medicaments) according to the proportion of a table 1, spraying the mixture on the surface of the supporting layer non-woven fabric through a spraying process at a flow rate of 2L/min, and drying to obtain the aldehyde-removing non-woven fabric; the weight percentage of each component in the aldehyde-removed non-woven fabric is shown in the table 1;
the average fiber diameter is 2.1 microns, and the gram weight is 25g/m2E12-grade (refer to EN1822) electret melt-blown nonwoven fabric is subjected to composite processing by a hot melt adhesive compound machine and an aldehyde-removing nonwoven fabric line to obtain aldehyde-removing nonwoven fabric filter cloth; the physical properties of the non-woven fabric filter cloth for removing aldehyde are shown in Table 1 (gram weight, resistance, efficiency for removing aldehyde, FCADR, processability).
Example 2
Porous particulate matter, porous particulate matter using silica, specific surface area 520m2G, pore volume 3.2 ml/g.
Polyester fibers having a fineness of 8.0dtex or 2.0dtex and an acrylic resin (Tg: 47 ℃ C., the same applies hereinafter) were subjected to a wet papermaking process to obtain a wet-process paper having a basis weight of 60g/m2A support layer nonwoven fabric of (a); fully mixing and uniformly stirring a silica porous particulate carrier with D50 of 10 microns, an aldehyde-removing functional medicament and the like (succinic dihydrazide is used as an experimental medicament in the embodiment, but is not limited to other aldehyde-removing medicaments) according to the proportion of table 1, spraying the mixture onto the surface of the supporting layer non-woven fabric through a spraying process at a flow rate of 2L/min, and drying to obtain the aldehyde-removing non-woven fabric; the weight percentage of each component in the aldehyde-removed non-woven fabric is shown in the table 1;
the average fiber diameter is 2.1 microns, and the gram weight is 25g/m2E12-grade (refer to EN1822) electret melt-blown nonwoven fabric is subjected to composite processing by a hot melt adhesive compound machine and an aldehyde-removing nonwoven fabric line to obtain aldehyde-removing nonwoven fabric filter cloth; the physical properties of the non-woven fabric filter cloth for removing aldehyde are shown in Table 1 (gram weight, resistance, efficiency for removing aldehyde, FCADR, processability).
Example 3
Porous particulate matter, porous particulate matter using silica, specific surface area 520m2G, pore volume 3.2 ml/g.
The polyester fiber with the fineness of 6.0dtex and 1.0dtex and acrylic resin (Tg is 47 ℃, the same below) are processed by a wet papermaking process to obtain the weight of 60g/m2Support layer nonwoven fabric of (1). Fully mixing and uniformly stirring a silica porous particulate carrier with D50 of 10 microns, an aldehyde-removing functional medicament and the like (succinic dihydrazide is used as an experimental medicament in the embodiment, but is not limited to other aldehyde-removing medicaments) according to the proportion of table 1, spraying the mixture onto the surface of the supporting layer non-woven fabric through a spraying process at a flow rate of 2L/min, and drying to obtain the aldehyde-removing non-woven fabric; the weight percentage of each component in the aldehyde-removed non-woven fabric is shown in the table 1;
the average fiber diameter is 2.1 microns, and the gram weight is 25g/m2E12-grade (refer to EN1822) electret melt-blown nonwoven fabric is subjected to composite processing by a hot melt adhesive compound machine and an aldehyde-removing nonwoven fabric line to obtain aldehyde-removing nonwoven fabric filter cloth; the physical properties of the non-woven fabric filter cloth for removing aldehyde are shown in Table 1 (gram weight, resistance, efficiency for removing aldehyde, FCADR, processability).
Example 4
Porous particulate, porous particulate using silica, specific surface area 520m2G, pore volume 3.2 ml/g.
The polyester fiber with the fineness of 6.0dtex, the vinylon fiber with the fineness of 1.0dtex and acrylic resin (Tg is 47 ℃, the same is carried out below) are subjected to a wet papermaking process to prepare the polyester fiber with the gram weight of 60g/m2A support layer nonwoven fabric of (a); fully mixing and uniformly stirring modified silica high-molecular dendritic polymer with D50 of 10 micrometers, silica porous particle carrier with D50 of 75 micrometers, silica porous particle carrier with D50 of 10 micrometers, aldehyde-removing functional medicament and the like (succinic dihydrazide is used as an experimental medicament in the embodiment, but not limited to other aldehyde-removing medicaments) according to the proportion in the table 1, spraying the mixture onto the surface of the supporting layer non-woven fabric through a spraying process at the flow rate of 2L/min, and drying to obtain aldehyde-removing non-woven fabric; the weight percentage of each component in the aldehyde-removed non-woven fabric is shown in the table 1;
the average fiber diameter is 2.1 microns, and the gram weight is 25g/m2E12-grade (refer to EN1822) electret melt-blown nonwoven fabric is subjected to composite processing by a hot melt adhesive compound machine and an aldehyde-removing nonwoven fabric line to obtain aldehyde-removing nonwoven fabric filter cloth; the physical properties of the non-woven fabric filter cloth for removing aldehyde are shown in Table 1 (gram weight, resistance, efficiency for removing aldehyde, FCADR, processability).
Example 5
Porous particulate matter, porous particulate matter using silica, specific surface area 520m2G, pore volume 3.2 ml/g.
Polyester fibers having a fineness of 8.0dtex or 2.0dtex and an acrylic resin (Tg: 47 ℃ C., the same applies hereinafter) were subjected to a wet papermaking process to obtain a wet-process paper having a basis weight of 54g/m2A support layer nonwoven fabric of (a); fully mixing and uniformly stirring a silica porous particulate carrier with D50 of 10 microns, an aldehyde-removing functional medicament and the like (succinic dihydrazide is used as an experimental medicament in the embodiment, but is not limited to other aldehyde-removing medicaments) according to the proportion of table 1, spraying the mixture onto the surface of the supporting layer non-woven fabric through a spraying process at a flow rate of 2L/min, and drying to obtain the aldehyde-removing non-woven fabric; the weight percentage of each component in the aldehyde-removed non-woven fabric is shown in the table 1;
the average fiber diameter is 2.1 microns, and the gram weight is 25g/m2E12 class (cf. EN1822) electret melt-blown nonwoven fabricCarrying out composite processing on an overheating glue-melting compound machine and the aldehyde-removing non-woven fabric to obtain aldehyde-removing non-woven fabric filter cloth; the physical properties of the non-woven fabric filter cloth for removing aldehyde are shown in Table 1 (gram weight, resistance, efficiency for removing aldehyde, FCADR, processability).
Comparative example 1
The polyester fiber with the fineness of 6dtex and acrylic resin are prepared into the basis weight of 60g/m by a wet papermaking process2A support layer nonwoven fabric of (a); a silica porous particulate support having a D50 value of 10 μm (specific surface area 130 m)2(0.5 ml/g) and aldehyde-removing functional agents (succinic dihydrazide is used as an experimental agent in the embodiment, but not limited to other aldehyde-removing agents) according to the proportion of table 1, fully mixing and stirring uniformly, spraying the mixture onto the surface of the supporting layer nonwoven fabric through a spraying process at a flow rate of 2L/min, and drying to obtain aldehyde-removing nonwoven fabric; the weight percentage of each component in the aldehyde-removed non-woven fabric is shown in the table 1;
the average fiber diameter is 2.1 microns, and the gram weight is 25g/m2E12-grade (refer to EN1822) electret melt-blown nonwoven fabric is subjected to composite processing by a hot melt adhesive compound machine and an aldehyde-removing nonwoven fabric line to obtain aldehyde-removing nonwoven fabric filter cloth; the physical properties of the non-woven fabric filter cloth for removing aldehyde are shown in Table 1 (gram weight, resistance, efficiency for removing aldehyde, FCADR, processability).
Comparative example 2
The polyester fiber with the fineness of 6.0dtex and 1.0dtex and the acrylic resin are processed by a wet papermaking process to prepare the polyester fiber with the gram weight of 50g/m2A support layer nonwoven fabric of (a); mixing and stirring a common high-molecular dendritic polymer carrier, an aldehyde-removing functional medicament and the like (succinic dihydrazide is used as an experimental medicament in the embodiment, but is not limited to other aldehyde-removing medicaments) fully and uniformly according to the proportion of table 1, spraying the mixture onto the surface of the supporting layer non-woven fabric through a spraying process at a flow rate of 2L/min, and drying to obtain the aldehyde-removing non-woven fabric; the weight percentage of each component in the aldehyde-removed non-woven fabric is shown in the table 1;
the average fiber diameter is 2.1 microns, and the gram weight is 25g/m2E12-grade (EN 1822) electret melt-blown nonwoven fabric is processed by compounding a hot melt adhesive compounding machine and an aldehyde-removing nonwoven fabric line to obtain an aldehyde-removing nonwoven fabric filterCloth; the physical properties of the non-woven fabric filter cloth for removing aldehyde are shown in Table 1 (gram weight, resistance, efficiency for removing aldehyde, FCADR, processability).
TABLE 1
1 ordinary high molecular dendritic polymer, 2 modified silica high molecular dendritic polymer, D50 ═ 10 um.
Resistance is the resistance of the support layer nonwoven.
As can be seen from the above table, the formaldehyde-removing nonwoven fabric of the present invention has the characteristics of low resistance, high formaldehyde adsorption amount, high stiffness, and low resistance.
Claims (10)
1. An aldehyde-scavenging nonwoven fabric characterized by: the fiber size of the fiber is 5.0-8.0dtex, and the coarse fibers account for 25-45% of the total weight; the fineness of the fine fibers is 10-2.0 dtex, and the fine fibers account for 5-20% of the total weight; the carrier contains inorganic porous fine particles, the D50 of the inorganic porous fine particles is 5-30 micrometers, and the inorganic porous fine particles account for 3-30% of the total weight; the glass transition temperature of the acrylic resin is 30-70 ℃, and the acrylic resin accounts for 25-40% of the total weight.
2. The aldehyde-removing nonwoven fabric of claim 1 wherein: the carrier contains inorganic porous coarse particles, and the D50 of the inorganic porous coarse particles is 40-80 microns and is 0.5-3 wt%.
3. The aldehyde-removing nonwoven fabric of claim 2 wherein: the specific surface area of the inorganic porous fine particles and the inorganic porous coarse particles is 300-600 m2/g, and the pore diameters of the inorganic porous fine particles and the inorganic porous coarse particles are less than 20nm and account for more than 80% of the total pore volume.
4. The aldehyde-removing nonwoven fabric of claim 1 wherein: the carrier also contains one of macromolecule dendritic polymer, macromolecule dendritic modified polymer or a mixture of the macromolecule dendritic polymer and the macromolecule dendritic modified polymer, and the content of the macromolecule dendritic modified polymer is 5-10% of the total weight.
5. The aldehyde-removing nonwoven fabric of claim 2 wherein: the inorganic porous fine particles contain silica dendritic modified polymers, and the content of the silica dendritic modified polymers accounts for 50-80% of the total weight of the inorganic porous coarse particles and the inorganic porous fine particles.
6. The aldehyde-removing nonwoven fabric of claim 1 wherein: also comprises 0.3-1.0 g/m2 of antibacterial agent.
7. A method for preparing aldehyde-removing non-woven fabric is characterized in that: the method comprises the following steps:
step (1): uniformly dispersing the coarse fibers and the fine fibers to prepare fiber slurry, mixing the fiber slurry with white water to form fiber slurry, forming by an inclined net, and finally forming a fiber net by vacuum water absorption;
step (2): coating acrylic resin on the surface of a fiber net, then drying in an oven at the speed of 15-40 m/min, reinforcing and forming to obtain a non-woven fabric;
and (3): the mixture of the carrier, the acrylic resin and the surfactant is attached to the non-woven fabric through a spraying, liquid tank padding or foam padding post-processing technology, and the aldehyde-removing non-woven fabric is prepared after drying.
8. The method for producing a non-woven fabric with aldehyde removed according to claim 7, wherein: the spraying process is preferably adopted in the step (3), and when the standard flow of the spraying holes is 0.3MPa, the flow is 0.5-2.0L/min.
9. The method for producing a non-woven fabric with aldehyde removed according to claim 7, wherein: in the acrylic resin coating process in the step (2) or the post-processing process in the step (3), a pigment or a disperse dye may be added for coloring.
10. Use of a non-woven fabric for removing aldehydes according to any one of claims 1 or 6 in an air filtration device or ventilation system.
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| CN112619287A (en) * | 2020-11-04 | 2021-04-09 | 海信（广东）空调有限公司 | Filter screen and preparation method thereof, air conditioner indoor unit with filter screen and air purifier |
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| CN112619287A (en) * | 2020-11-04 | 2021-04-09 | 海信（广东）空调有限公司 | Filter screen and preparation method thereof, air conditioner indoor unit with filter screen and air purifier |
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