阅读说明：本技术 一种阻燃芳纶空气滤纸及其制备方法和应用 (Flame-retardant aramid fiber air filter paper and preparation method and application thereof ) 是由 惠岚峰 孙晚红 刘子琪 于 2021-01-26 设计创作，主要内容包括：本发明公开了一种阻燃芳纶空气滤纸,由以下重量份数的原料组成：针叶木浆25-40份、阔叶木浆10-20份、芳纶纤维10-15份、丝光浆6-10份、玻璃纤维6-10份、阻燃剂8-15份、聚丙烯腈纤维4-6份、聚芳噁二唑纤维3-5份,酚醛树脂3-6份,苯丙乳液2-4份,丙烯酸乳液2-3份,滑石粉1-2份和抄纸助剂3-5份；该空气滤纸不仅阻燃效果好,而且强度性能好,使用寿命长。(The invention discloses flame-retardant aramid fiber air filter paper which is prepared from the following raw materials in parts by weight: 25-40 parts of softwood pulp, 10-20 parts of hardwood pulp, 10-15 parts of aramid fiber, 6-10 parts of mercerized pulp, 6-10 parts of glass fiber, 8-15 parts of flame retardant, 4-6 parts of polyacrylonitrile fiber, 3-5 parts of polyaryl oxadiazole fiber, 3-6 parts of phenolic resin, 2-4 parts of styrene-acrylic emulsion, 2-3 parts of acrylic emulsion, 1-2 parts of talcum powder and 3-5 parts of papermaking auxiliary agent; the air filter paper has the advantages of good flame retardant effect, good strength performance and long service life.)

1. The flame-retardant aramid air filter paper is characterized by comprising the following raw materials in parts by weight: 25-40 parts of softwood pulp, 10-20 parts of hardwood pulp, 10-15 parts of aramid fiber, 6-10 parts of mercerized pulp, 6-10 parts of glass fiber, 8-15 parts of flame retardant, 4-6 parts of polyacrylonitrile fiber, 3-5 parts of polyaryl oxadiazole fiber, 3-6 parts of phenolic resin, 2-4 parts of styrene-acrylic emulsion, 2-3 parts of acrylic emulsion, 1-2 parts of talcum powder and 3-5 parts of papermaking auxiliary agent.

2. The flame-retardant aramid air filter paper as claimed in claim 1, characterized in that: the composite material consists of the following raw materials in optimal parts by weight: 28 parts of softwood pulp, 12 parts of hardwood pulp, 13 parts of aramid fiber, 8 parts of mercerized pulp, 8 parts of glass fiber, 10 parts of flame retardant, 5 parts of polyacrylonitrile fiber, 3 parts of polyaryl oxadiazole fiber, 4 parts of phenolic resin, 3 parts of styrene-acrylic emulsion, 2 parts of acrylic emulsion, 1 part of talcum powder and 3 parts of papermaking auxiliary agent.

3. The flame-retardant aramid air filter paper as claimed in claim 2, wherein the flame retardant is a mixture of N, N' -piperazine tetraphenoxy phosphoramidate and decabromodiphenylethane fiber, and the weight ratio of the flame retardant is (3-6) to (3-6).

4. The flame-retardant aramid air filter paper as claimed in claim 1, characterized in that: the papermaking auxiliary agent comprises a defoaming agent, a wet strength agent and a dry strength agent cationic polyacrylamide, and the weight ratio of the components is (1-2): (3-4): (6-8).

5. The flame-retardant aramid air filter paper as claimed in claim 4, characterized in that: the defoaming agent comprises: polymerizing the mixture of propylene oxide and ethylene oxide, wherein the weight ratio of the propylene oxide to the ethylene oxide is (2-5) to (5-8).

6. The flame-retardant aramid air filter paper as claimed in claim 4, characterized in that: the wet strength agent is polyamide polyepichlorohydrin.

7. The preparation method of the flame-retardant aramid air filter paper as claimed in any one of claims 1 to 6, characterized in that: the method comprises the following steps:

1) weighing: weighing the raw materials in parts by weight;

2) pulping and mixing: mixing and pulping the softwood pulp, the mercerized pulp and the hardwood pulp obtained in the step 1), and sequentially adding a defoaming agent, aramid fibers, a flame retardant, glass fibers, polyacrylonitrile fibers and polyaryl oxadiazole fibers during pulping to obtain a mixture;

3) adjusting the pH value: adjusting the pH value of the mixture obtained in the step 2) to 3-5 by using dilute sulfuric acid, then adding talcum powder, wet strength agent and dry strength agent, and stirring to obtain mixed slurry;

4) molding: adjusting the solid content of the mixed slurry obtained in the step 3) to be 0.5-2%, forming by a standard paper sheet former, and then carrying out suction dewatering on the formed wet paper sheet under the condition of 0.05-0.2Mpa vacuum degree until the water content is 3-5% to obtain a dewatered paper sheet;

5) dipping: compounding and mixing phenolic resin, acrylic emulsion and styrene-acrylic emulsion to prepare impregnation liquid, and immersing the dehydrated paper sheet prepared in the step 4) into the impregnation liquid for 15-30s to obtain an impregnated paper sheet;

6) drying: and (3) drying the impregnated paper sheet obtained in the step 5), and finishing and leveling to obtain the flame-retardant aramid air filter paper.

8. The preparation method of the flame-retardant aramid air filter paper as claimed in claim 7, wherein in the step 2), the mixing and beating are carried out to 20-40 ° SR.

9. The preparation method of the flame-retardant aramid air filter paper as claimed in claim 7, wherein in the step 6), the drying is performed at 130-150 ℃.

Technical Field

The invention relates to the technical field of high polymer materials, in particular to flame-retardant aramid fiber air filter paper and a preparation method and application thereof.

Background

The automobile air filter paper is an important filter material in the automobile industry, is one of main constituent materials for manufacturing the air filter, is a very important special paper variety, and with the rapid development of the automobile industry in China, the development and the application of a new variety of the automobile filter paper are promoted, so that the development prospect of the automobile air filter paper is wide.

The automobile air filter has the function of effectively filtering impurities in air sucked by an automobile air inlet system, so that the fault probability of an automobile engine is reduced, and the service life of the engine is prolonged. In an air intake system of an engine, because a large amount of heat needs to be released when a fuel engine works, and the spontaneous combustion accident of an automobile engine can be caused by the backfire of combustible matters with sparks or cylinders sucked in an air filter, the air filter paper used in the production of the air filter is required to have certain flame retardant performance so as to ensure the normal use of the air filter under the above state. The air filter paper produced by the traditional method has the disadvantages of non-lasting flame-retardant effect, poor flame-retardant effect and even no flame-retardant effect, so that the air filter has short service life and poor weather resistance, and brings serious potential safety hazard and energy loss to normal running of an automobile.

Therefore, the problem to be solved by those skilled in the art is how to provide an air filter paper for a vehicle with good flame retardant effect and good durability.

Disclosure of Invention

In view of the above, the invention provides the flame-retardant aramid fiber air filter paper which is good in flame-retardant effect, good in strength performance and long in service life.

In order to achieve the purpose, the invention adopts the following technical scheme:

the flame-retardant aramid air filter paper is characterized by comprising the following raw materials in parts by weight: 25-40 parts of softwood pulp, 10-20 parts of hardwood pulp, 10-15 parts of aramid fiber, 6-10 parts of mercerized pulp, 6-10 parts of glass fiber, 8-15 parts of flame retardant, 4-6 parts of polyacrylonitrile fiber, 3-5 parts of polyaryl oxadiazole fiber, 3-6 parts of phenolic resin, 2-4 parts of styrene-acrylic emulsion, 2-3 parts of acrylic emulsion, 1-2 parts of talcum powder and 3-5 parts of papermaking auxiliary agent.

As the preferable technical scheme of the invention, the flame-retardant aramid fiber air filter paper is prepared from the following raw materials in the optimal parts by weight: 28 parts of softwood pulp, 12 parts of hardwood pulp, 13 parts of aramid fiber, 8 parts of mercerized pulp, 8 parts of glass fiber, 10 parts of flame retardant, 5 parts of polyacrylonitrile fiber, 3 parts of polyaryl oxadiazole fiber, 4 parts of phenolic resin, 3 parts of styrene-acrylic emulsion, 2 parts of acrylic emulsion, 1 part of talcum powder and 3 parts of papermaking auxiliary agent.

The technical effect achieved by the technical scheme is as follows: the aramid fiber is a synthetic flame-retardant fiber with good heat resistance, fire resistance, chemical corrosion resistance and mechanical property, the continuous stable working temperature of the aramid fiber can reach about 190 ℃, the decomposition temperature is more than 400 ℃, the aramid fiber can be used in the environment with hot air and high-temperature smoke, and becomes an important basic raw material of an advanced flame-retardant and high-temperature gas filtering material.

As a preferable technical scheme of the invention, the flame retardant is a mixture of N, N' -piperazine tetraphenoxy phosphoramidate and decabromodiphenylethane fiber, and the weight portion ratio is (3-6) to (3-6).

As a preferable technical scheme of the invention, the papermaking auxiliary agent comprises a defoaming agent, a wet strength agent and a dry strength agent cationic polyacrylamide, and the weight ratio of the components is (1-2) to (3-4) to (6-8).

As a preferred embodiment of the present invention, the defoaming agent includes: polymerizing the mixture of propylene oxide and ethylene oxide, wherein the weight ratio of the propylene oxide to the ethylene oxide is (2-5) to (5-8).

As a preferable technical scheme of the invention, the wet strength agent is polyamide polyepichlorohydrin.

The preparation method of the flame-retardant aramid air filter paper is characterized by comprising the following steps of: the method comprises the following steps:

1) weighing: weighing the raw materials in parts by weight;

2) pulping and mixing: mixing and pulping the softwood pulp, the mercerized pulp and the hardwood pulp obtained in the step 1), and sequentially adding a defoaming agent, aramid fibers, a flame retardant, glass fibers, polyacrylonitrile fibers and polyaryl oxadiazole fibers during pulping to obtain a mixture;

3) adjusting the pH value: adjusting the pH value of the mixture obtained in the step 2) by using dilute sulfuric acid, then adding talcum powder, a wet strength agent and a dry strength agent, and stirring to obtain mixed slurry;

4) molding: adjusting the solid content of the mixed slurry obtained in the step 3) to be 0.5-2%, forming by a standard paper sheet former, and then performing suction dehydration on the formed wet paper sheet under the condition of 0.05-0.2Mpa vacuum degree to obtain a dehydrated paper sheet;

5) dipping: compounding and mixing phenolic resin, acrylic emulsion and styrene-acrylic emulsion to prepare impregnation liquid, and immersing the dehydrated paper sheet prepared in the step 4) into the impregnation liquid for 15-30s to obtain an impregnated paper sheet;

6) drying: and (3) drying and finishing the impregnated paper sheet obtained in the step 5) to obtain the flame-retardant aramid fiber air filter paper.

As a preferable technical scheme of the invention, in the step 2), the mixing and pulping are carried out to obtain the SR of 20-40 DEG

As a preferable technical scheme of the invention, in the step 6), the drying is performed at 130-150 ℃.

The flame-retardant aramid fiber air filter paper prepared by the preparation method is applied to preparation of an automobile filter.

In summary, compared with the prior art, the invention achieves the technical effects that:

(1) according to the invention, the aramid fiber is added into the raw materials, so that the flame retardant property of the air filter paper for the vehicle is greatly improved;

(2) the mixed liquid obtained by compounding the phenolic resin, the acrylic emulsion and the styrene-acrylic emulsion is used for replacing the conventional styrene-acrylic emulsion, so that the using amount of the flame retardant can be greatly reduced, and the mechanical property and the filtering property of the air filter paper can not be reduced; according to the invention, softwood pulp, mercerized pulp, hardwood pulp, aramid fiber, a flame retardant, glass fiber, polyacrylonitrile fiber and polyaryl oxadiazole fiber are matched for use, organic plant fiber and inorganic fiber are reasonably matched to exert the respective characteristics and performances of the organic plant fiber and the inorganic fiber, so that the total consumption of the plant fiber is effectively reduced, especially the consumption of the mercerized pulp is greatly reduced, and the raw material cost of the aramid flame-retardant air filter paper is reduced;

(3) the flame-retardant air filter paper prepared by the invention has the advantages of good air permeability, high strength, high filtering precision, good wear resistance, long service life and obvious flame-retardant effect.

Detailed Description

The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

The flame-retardant aramid air filter paper is prepared from the following raw materials in parts by weight: 25 parts of softwood pulp, 10 parts of hardwood pulp, 10 parts of aramid fiber, 6 parts of mercerized pulp, 6 parts of glass fiber, 8 parts of a mixture of N, N' -piperazine tetraphenoxy phosphoramidate and decabromodiphenylethane fiber (the weight part ratio is 3:3), 6 parts of polyacrylonitrile fiber, 5 parts of polyaryl oxadiazole fiber, 3 parts of phenolic resin, 2 parts of styrene-acrylic emulsion, 2.5 parts of acrylic emulsion, 1 part of talcum powder, 4 parts of a mixture of a defoaming agent, polyamide polyepichlorohydrin and a dry strength agent cationic polyacrylamide, and the weight part ratio is 1:4: 6; wherein the defoaming agent is a mixture of agent polymerization propylene oxide and ethylene oxide, and the weight ratio is 3: 7.

The preparation process comprises the following steps:

(1) mixing and pulping softwood pulp, mercerized pulp and hardwood pulp to 30-degree SR, adding a mixture of polymerized propylene oxide and ethylene oxide in the pulping process, and then adding a mixture of aramid fiber, N' -piperazine tetraphenyloxyphosphoramidate and decabromodiphenylethane fiber, glass fiber, polyacrylonitrile fiber and polyaryl oxadiazole fiber;

(2) after the pulping is finished, adjusting the pH value by using dilute sulfuric acid, adding talcum powder, wet strength agent and dry strength agent, and fully and uniformly stirring to prepare mixed slurry;

(3) adding water to adjust the solid content of the mixed pulp to be 0.5-2%, molding the mixed pulp by a standard paper sheet former, and then pumping and dehydrating the molded wet paper sheet under the condition of 0.06Mpa vacuum degree;

(4) compounding and mixing phenolic resin, acrylic emulsion and styrene-acrylic emulsion to prepare impregnation liquid, and impregnating the paper sheet prepared in the step (3) in the impregnation liquid for 30 seconds;

(5) and (4) drying and finishing the impregnated paper sheet obtained in the step (4) at the temperature of 150 ℃ to obtain the flame-retardant aramid fiber air filter paper.

Example 2

The flame-retardant aramid air filter paper is prepared from the following raw materials in parts by weight: 28 parts of softwood pulp, 12 parts of hardwood pulp, 13 parts of aramid fiber, 8 parts of mercerized pulp, 8 parts of glass fiber, 10 parts of a mixture of N, N' -piperazine tetraphenoxy phosphoramidate and decabromodiphenylethane fiber (the weight part ratio is 4:4), 5 parts of polyacrylonitrile fiber, 3 parts of polyaryl oxadiazole fiber, 4 parts of phenolic resin, 3 parts of styrene-acrylic emulsion, 2 parts of acrylic emulsion, 1 part of talcum powder, 3 parts of a defoaming agent, 3 parts of a mixture of polyamide polyepichlorohydrin and dry strength agent cationic polyacrylamide, the weight part ratio is 2:4:7, and the defoaming agent is a mixture of polymerized propylene oxide and ethylene oxide, and the weight part ratio is 2: 8.

The preparation process comprises the following steps:

(1) mixing and pulping softwood pulp, mercerized pulp and hardwood pulp to 20-degree SR, adding a defoaming agent in the pulping process, and then adding aramid fiber, a mixture of N, N' -piperazine tetraphenyloxyphosphoramidate and decabromodiphenylethane fiber, glass fiber, polyacrylonitrile fiber and polyaryl oxadiazole fiber;

(2) after the pulping is finished, adjusting the pH value by using dilute sulfuric acid, adding talcum powder, a wet strength agent and a dry strength agent, and fully and uniformly stirring to prepare mixed slurry;

(3) adding water to adjust the solid content of the mixed pulp to be 0.5-2%, molding the mixed pulp by a standard paper sheet former, and then pumping and dehydrating the molded wet paper sheet under the condition of 0.05Mpa of vacuum degree;

(4) compounding and mixing phenolic resin, acrylic emulsion and styrene-acrylic emulsion to prepare impregnation liquid, and impregnating the paper sheet prepared in the step (3) in the impregnation liquid for 20 s;

(5) and (4) drying and finishing the impregnated paper sheet obtained in the step (4) at 140 ℃ to obtain the aramid flame-retardant air filter paper.

Example 3

The flame-retardant aramid air filter paper is prepared from the following raw materials in parts by weight: 40 parts of softwood pulp, 20 parts of hardwood pulp, 15 parts of aramid fiber, 10 parts of mercerized pulp, 10 parts of glass fiber, 15 parts of a mixture of N, N' -piperazine tetraphenoxy phosphoramidate and decabromodiphenylethane fiber (the weight part ratio is 4:6), 6 parts of polyacrylonitrile fiber, 4 parts of polyaryl oxadiazole fiber, 6 parts of phenolic resin, 4 parts of styrene-acrylic emulsion, 3 parts of acrylic emulsion, 1.5 parts of talcum powder, 5 parts of a defoaming agent, a mixture of polyamide polyepichlorohydrin and dry strength agent cationic polyacrylamide, the weight part ratio is 1:4:7, and the defoaming agent is a mixture of polymerized epoxypropane and ethylene oxide, and the weight part ratio is 5: 5.

The preparation process comprises the following steps:

(1) mixing and pulping softwood pulp, mercerized pulp and hardwood pulp to 40-degree SR, adding a mixture of polymerized propylene oxide and ethylene oxide in the pulping process, and then adding aramid fiber, N' -piperazine tetraphenyloxyphosphoramidate, decabromodiphenylethane fiber, glass fiber, polyacrylonitrile fiber and polyaryl oxadiazole fiber;

(2) after the pulping is finished, adjusting the pH value by using dilute sulfuric acid, adding talcum powder, a wet strength agent and a dry strength agent, and fully and uniformly stirring to prepare mixed slurry;

(3) adding water to adjust the solid content of the mixed pulp to be 0.5-2%, molding the mixed pulp by a standard paper sheet former, and then pumping and dehydrating the molded wet paper sheet under the condition of 0.2Mpa vacuum degree;

(4) compounding and mixing phenolic resin, acrylic emulsion and styrene-acrylic emulsion to prepare impregnation liquid, and impregnating the paper sheet prepared in the step (3) in the impregnation liquid for 15 seconds;

(5) and (4) drying and finishing the impregnated paper sheet obtained in the step (4) at 130 ℃ to obtain the aramid flame-retardant air filter paper.

Example 4

The flame-retardant aramid air filter paper is prepared from the following raw materials in parts by weight: 30 parts of softwood pulp, 12 parts of hardwood pulp, 10 parts of aramid fiber, 8 parts of mercerized pulp, 8 parts of glass fiber, 10 parts of a mixture (the weight part ratio is 6:4) of N, N' -piperazine tetraphenyloxyphosphoramidate and decabromodiphenylethane fiber, 6 parts of polyacrylonitrile fiber, 4 parts of polyaryl oxadiazole fiber, 6 parts of phenolic resin, 3 parts of styrene-acrylic emulsion, 2 parts of acrylic emulsion, 1 part of talcum powder, 3 parts of a mixture of a defoaming agent, polyamide polyepichlorohydrin and a dry strength agent cationic polyacrylamide, wherein the weight part ratio is 2:3: 7; the defoaming agent is a mixture of polymerized propylene oxide and ethylene oxide, and the weight ratio of the defoaming agent to the ethylene oxide is 4: 8.

The preparation process comprises the following steps:

(1) mixing and pulping softwood pulp, mercerized pulp and hardwood pulp to 35-degree SR, adding a defoaming agent in the pulping process, and then adding aramid fiber, a flame retardant N, N' -piperazine tetraphenyloxyphosphoramidate, decabromodiphenylethane fiber, glass fiber, polyacrylonitrile fiber and polyaryl oxadiazole fiber;

(2) after the pulping is finished, adjusting the pH value by using dilute sulfuric acid, adding talcum powder, a wet strength agent and a dry strength agent, and fully and uniformly stirring to prepare mixed slurry;

(3) adding water to adjust the solid content of the mixed pulp to be 0.5-2%, molding the mixed pulp by a standard paper sheet former, and then pumping and dehydrating the molded wet paper sheet under the condition of 0.1Mpa vacuum degree;

(4) compounding and mixing phenolic resin, acrylic emulsion and styrene-acrylic emulsion to prepare impregnation liquid, and impregnating the paper sheet prepared in the step (3) in the impregnation liquid for 25 s;

(5) and (4) drying and finishing the impregnated paper sheet obtained in the step (4) at 140 ℃ to obtain the aramid flame-retardant air filter paper.

Example 5

The flame-retardant aramid air filter paper is prepared from the following raw materials in parts by weight: 30 parts of softwood pulp, 12 parts of hardwood pulp, 10 parts of mercerized pulp, 8 parts of glass fiber, 10 parts of a mixture of N, N' -piperazine tetraphenoxy phosphoramidate and decabromodiphenylethane fiber (the weight part ratio is 6:4), 6 parts of polyacrylonitrile fiber, 4 parts of polyaryl oxadiazole fiber, 6 parts of phenolic resin, 3 parts of styrene-acrylic emulsion, 2 parts of acrylic emulsion, 1 part of talcum powder, 3 parts of a mixture of a defoaming agent, polyamide polyepichlorohydrin and a dry strength agent cationic polyacrylamide, and the weight part ratio is 2:3:7, wherein the defoaming agent is a mixture of epoxy propane and ethylene oxide, and the weight part ratio is 4: 8.

the preparation process comprises the following steps:

(1) mixing and pulping softwood pulp, mercerized pulp and hardwood pulp to 35-degree SR, adding a mixture of polymerized propylene oxide and ethylene oxide in the pulping process, and then adding N, N' -piperazine tetraphenoxy phosphoramidate, decabromodiphenylethane fiber, glass fiber, polyacrylonitrile fiber and polyaryl oxadiazole fiber;

(2) after the pulping is finished, adjusting the pH value by using dilute sulfuric acid, adding talcum powder, a wet strength agent and a dry strength agent, and fully and uniformly stirring to prepare mixed slurry;

(3) adding water to adjust the solid content of the mixed pulp to be 0.5-2%, molding the mixed pulp by a standard paper sheet former, and then pumping and dehydrating the molded wet paper sheet under the condition of 0.1Mpa vacuum degree;

(4) compounding and mixing phenolic resin, acrylic emulsion and styrene-acrylic emulsion to prepare impregnation liquid, and impregnating the paper sheet prepared in the step (3) in the impregnation liquid for 25 s;

(5) and (4) drying and finishing the impregnated paper sheet obtained in the step (4) at 140 ℃ to obtain the aramid flame-retardant air filter paper.

Example 5 versus example 4, the main difference is that no aramid fiber was used as determined in example 5.

The air permeability, maximum pore size, average pore size, elongation, burst strength, tensile strength, filtration accuracy, impurity removal rate and flame retardancy of the flame-retardant air filter papers prepared in examples 1 to 5 were measured, and the results are shown in table 1.

TABLE 1 Performance index of flame-retardant paper

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.