阅读说明：本技术 一种高效抗菌聚四氟乙烯微孔膜及其制备方法 (High-efficiency antibacterial polytetrafluoroethylene microporous membrane and preparation method thereof ) 是由 田登攀 李俊泳 田世岩 于 2021-09-07 设计创作，主要内容包括：本发明涉及一种高效抗菌聚四氟乙烯微孔膜及其制备方法,制备方法包括原料制备工艺和成膜工艺；原料制备工艺包括：先将1～10重量份的锌离子抗菌剂加入到100重量份的无水乙醇中,混合搅拌得到混合物A；再将5～15重量份的混合物A加入100重量份的烃类添加剂中得到混合物B；将PTFE分散树脂粉加入混合物B,PTFE分散树脂粉与混合物B的重量份比例为100：15～25,搅拌均匀形成糊膏状的原料。直接将锌离子抗菌剂混合在聚四氟乙烯微孔膜的原料中,由本制备方法制得的聚四氟乙烯微孔膜内均匀分布有锌离子,大大的提高了聚四氟乙烯微孔膜的抗菌性能；锌无色无味,不改变产品原色,聚四氟乙烯微孔膜可以用在个人防护、空气过滤、医用材料等领域。(The invention relates to a high-efficiency antibacterial polytetrafluoroethylene microporous membrane and a preparation method thereof, wherein the preparation method comprises a raw material preparation process and a film forming process; the preparation process of the raw materials comprises the following steps: adding 1-10 parts by weight of zinc ion antibacterial agent into 100 parts by weight of absolute ethyl alcohol, and mixing and stirring to obtain a mixture A; adding 5-15 parts by weight of the mixture A into 100 parts by weight of a hydrocarbon additive to obtain a mixture B; adding PTFE dispersion resin powder into the mixture B, wherein the weight ratio of the PTFE dispersion resin powder to the mixture B is 100: 15-25, and uniformly stirring to form a paste raw material. The zinc ion antibacterial agent is directly mixed in the raw material of the polytetrafluoroethylene microporous membrane, and zinc ions are uniformly distributed in the polytetrafluoroethylene microporous membrane prepared by the preparation method, so that the antibacterial performance of the polytetrafluoroethylene microporous membrane is greatly improved; the zinc is colorless and tasteless, and does not change the primary color of the product, and the polytetrafluoroethylene microporous membrane can be used in the fields of personal protection, air filtration, medical materials and the like.)

1. A preparation method of a high-efficiency antibacterial polytetrafluoroethylene microporous membrane is characterized by comprising the following steps: comprises a raw material preparation process and a film forming process;

the preparation process of the raw materials comprises the following steps:

adding 1-10 parts by weight of zinc ion antibacterial agent into 100 parts by weight of absolute ethyl alcohol, and mixing and stirring to obtain a mixture A;

adding 5-15 parts by weight of the mixture A into 100 parts by weight of a hydrocarbon additive to obtain a mixture B;

adding PTFE dispersion resin powder into the mixture B, wherein the weight ratio of the PTFE dispersion resin powder to the mixture B is 100: 15-25, and uniformly stirring to form a paste raw material.

2. The method for preparing the high-efficiency antibacterial polytetrafluoroethylene microporous membrane according to claim 1, characterized by comprising the following steps: the hydrocarbon additive comprises one or more of isoparaffin, petroleum ether, solvent oil and paraffin oil.

3. The method for preparing the high-efficiency antibacterial polytetrafluoroethylene microporous membrane according to claim 1, characterized by comprising the following steps: in the preparation process of the raw materials, PTFE dispersed resin powder is screened by a 30-mesh sieve, and larger powder particles are filtered; and after stirring the PTFE dispersed resin powder and the mixture B, standing for 24 hours at 40-60 ℃ to fully mix the PTFE dispersed resin powder and the mixture B.

4. The method for preparing the high-efficiency antibacterial polytetrafluoroethylene microporous membrane according to claim 1, characterized by comprising the following steps: in the preparation process of the raw materials, 1-10 parts by weight of zinc ion antibacterial agent is added into 100 parts by weight of absolute ethyl alcohol, and the mixture A is obtained by mixing and stirring for 30-60 minutes at a stirring speed of 1000-1500 r/min; and adding 5-15 parts by weight of the mixture A into 100 parts by weight of a hydrocarbon additive to obtain a mixture B, and stirring for 5-20 minutes at a stirring speed of 500-1000 r/min.

5. The method for preparing the high-efficiency antibacterial polytetrafluoroethylene microporous membrane according to claim 1, characterized by comprising the following steps: the film forming process comprises

Blank preparation: adding the raw materials into a blank making machine to press a blank body;

and (3) push forming: processing the blank into round bars and keeping the round bars in water;

rolling: fishing out the round strips from the water tank, and pressing into a film-shaped coil stock with the thickness of 0.1-0.3 mm;

removing the hydrocarbon additive: placing the film coil stock in a closed oven to remove the hydrocarbon additive;

stretching to form a film: stretching the film-shaped coil stock from which the hydrocarbon additive is removed into a microporous film;

and (3) curing and sintering: sintering and curing the stretched microporous membrane.

6. The method for preparing the high-efficiency antibacterial polytetrafluoroethylene microporous membrane according to claim 5, characterized by comprising the following steps: the stretch film forming process comprises the following steps:

longitudinally stretching the material belt without the hydrocarbon additive at the temperature of 180-260 ℃ to obtain a base belt with the porosity of 25-96%;

then, under the temperature condition of 150-280 ℃, the longitudinal and transverse stretching is carried out simultaneously until the width of the film is 1.5-2.5 m and the thickness is 5-30 μm.

7. The method for preparing the high-efficiency antibacterial polytetrafluoroethylene microporous membrane according to claim 5, characterized by comprising the following steps: the process for removing the hydrocarbon additive comprises the following steps:

and (3) placing the rolled film-shaped coil stock in a closed oven, and placing for 30-60 min at 200-260 ℃.

8. The method for preparing the high-efficiency antibacterial polytetrafluoroethylene microporous membrane according to claim 5, characterized by comprising the following steps: the blank making process comprises the following steps:

and (3) filling the paste raw material into a blank barrel of a briquetting machine, controlling the descending speed of the plunger to be less than 75 mm/min and the pressure to be 2-5 MPa, and repeatedly pressing for 15-30 min at 40-60 ℃.

9. The method for preparing the high-efficiency antibacterial polytetrafluoroethylene microporous membrane according to claim 5, characterized by comprising the following steps: the push forming process comprises the following steps:

and (3) placing the blank body on a pushing press, pushing the blank body at 40-60 ℃ to form round bars with the diameter of 10-20 mm, and keeping the round bars in a water tank at 45-60 ℃.

10. A highly effective antibacterial polytetrafluoroethylene microporous membrane produced by the production method according to any one of claims 1 to 9.

Technical Field

The invention relates to a high-efficiency antibacterial polytetrafluoroethylene microporous membrane and a preparation method thereof.

Background

With the increasing importance of people on health, the requirements on antibacterial fibers in life are more and more, such as antibacterial masks, antibacterial filter elements, antibacterial clothes and the like, and after 2000 years, the nanometer fibers are applied to the antibacterial fibers and show the superiority of nanometer materials.

At present, the application of the antibacterial fiber is mainly divided into two types:

the first is to attach inorganic nanometer antibacterial agent such as nanometer silver, nanometer copper and the like on the non-woven fabric fibers by spraying, soaking, depositing and other modes, and the mode can play a certain antibacterial role, but because the non-woven fabric fibers are diluted and have larger pore diameters, bacteria and viruses which can be attached on the non-woven fabric fibers are less, and the corresponding sterilization effect is limited.

The second type is a polytetrafluoroethylene microporous membrane containing a nano-silver antibacterial agent, when the polytetrafluoroethylene microporous membrane is produced, the antibacterial agent is directly mixed in raw materials, such as CN 102527248B, and because the polytetrafluoroethylene microporous membrane has small gaps, bacteria and viruses can be intercepted on the surface of the polytetrafluoroethylene microporous membrane, silver ions can be effectively sterilized, the first type of problem of poor sterilization effect is solved, but the nano-silver is easy to discolor in actual use, so that the application field of the nano-silver is limited, for example, Yuanpeng and the like refer to the problem that the silver ions are not stable enough and are easy to discolor in the research progress of 'silver-series inorganic antibacterial agent' in chemical minerals and processing (10 th year 2002), and the application of the nano-silver is limited; in the material report of 'research progress of silver-based inorganic antibacterial materials' in 2013, 9 and 10 of Wangjing et al, it is mentioned that the silver-based inorganic antibacterial materials are active in chemical properties and are easy to be converted into brown silver oxide or black simple substance silver through ultraviolet reduction because of containing silver ions, so that the antibacterial property is reduced after the silver ions are discolored, and white or light-colored products cannot be applied.

Meanwhile, in view of the difficulty in metabolizing silver in human body and the unclear toxicity of nano silver, the application of nano silver to textiles has been limited in the united states and the european union.

Disclosure of Invention

The invention aims to solve the technical problem of providing a high-efficiency antibacterial polytetrafluoroethylene microporous membrane and a preparation method thereof.

In order to solve the technical problems, the technical scheme of the invention is as follows: a preparation method of a high-efficiency antibacterial polytetrafluoroethylene microporous membrane comprises a raw material preparation process and a film forming process;

the preparation process of the raw materials comprises the following steps:

adding 1-10 parts by weight of zinc ion antibacterial agent into 100 parts by weight of absolute ethyl alcohol, and mixing and stirring to obtain a mixture A;

adding 5-15 parts by weight of the mixture A into 100 parts by weight of a hydrocarbon additive to obtain a mixture B;

adding PTFE dispersion resin powder into the mixture B, wherein the weight ratio of the PTFE dispersion resin powder to the mixture B is 100: 15-25, and uniformly stirring to form a paste raw material.

As a preferred technical scheme, the hydrocarbon additive comprises one or more of isoparaffin, petroleum ether, solvent oil and paraffin oil.

As a preferred technical scheme, in the preparation process of the raw materials, PTFE dispersed resin powder is screened by a 30-mesh sieve, and larger powder particles are filtered; and after stirring the PTFE dispersed resin powder and the mixture B, standing for 24 hours at 40-60 ℃ to fully mix the PTFE dispersed resin powder and the mixture B.

According to the preferable technical scheme, in the raw material preparation process, 1-10 parts by weight of zinc ion antibacterial agent is added into 100 parts by weight of absolute ethyl alcohol, and the mixture A is obtained through mixing and stirring for 30-60 minutes at the stirring speed of 1000-1500 r/min; and adding 5-15 parts by weight of the mixture A into 100 parts by weight of a hydrocarbon additive to obtain a mixture B, and stirring for 5-20 minutes at a stirring speed of 500-1000 r/min.

As a preferred technical scheme, the film forming process comprises

Blank preparation: adding the raw materials into a blank making machine to press a blank body;

and (3) push forming: processing the blank into round bars and keeping the round bars in water;

rolling: fishing out the round strips from the water tank, and pressing into a film-shaped coil stock with the thickness of 0.1-0.3 mm;

removing the hydrocarbon additive: placing the film coil stock in a closed oven to remove the hydrocarbon additive;

stretching to form a film: stretching the film-shaped coil stock from which the hydrocarbon additive is removed into a microporous film;

and (3) curing and sintering: sintering and curing the stretched microporous membrane.

As a preferred technical solution, the stretch film forming process includes:

longitudinally stretching the material belt without the hydrocarbon additive at the temperature of 180-260 ℃ to obtain a base belt with the porosity of 25-96%;

then, under the temperature condition of 150-280 ℃, longitudinal and transverse stretching is carried out simultaneously until the width of the film is 1.5-2.5 m and the thickness is 5-30 μm.

As a preferred technical scheme, the process for removing the hydrocarbon additive comprises the following steps:

and (3) placing the rolled film-shaped coil stock in a closed oven, and placing for 30-60 min at 200-260 ℃.

As a preferred technical scheme, the blank making process comprises the following steps:

and (3) filling the paste raw material into a blank barrel of a briquetting machine, controlling the descending speed of the plunger to be less than 75 mm/min and the pressure to be 2-5 MPa, and repeatedly pressing for 15-30 min at 40-60 ℃.

As a preferable aspect, the press molding process includes:

and (3) placing the blank body on a pushing press, pushing the blank body at 40-60 ℃ to form round bars with the diameter of 10-20 mm, and keeping the round bars in a water tank at 45-60 ℃.

An efficient antibacterial polytetrafluoroethylene microporous membrane is prepared by any one of the preparation methods.

The preparation method of the high-efficiency antibacterial polytetrafluoroethylene microporous membrane directly mixes the zinc ion antibacterial agent in the raw material of the polytetrafluoroethylene microporous membrane, so that zinc ions exist in the polytetrafluoroethylene microporous membrane instead of arranging the antibacterial coating, and the antibacterial performance of the polytetrafluoroethylene microporous membrane is greatly improved. The preparation method comprises the steps of adding the metal zinc ion antibacterial agent into the anhydrous ethanol auxiliary agent, uniformly mixing according to a certain proportion, adding into the alkane additive, uniformly mixing, and finally adding into the PTFE dispersion resin, so that the anhydrous ethanol is used as a grafting carrier of the metal zinc ion and the alkane additive, and the industrial problem that the metal zinc ion antibacterial agent and the hydrocarbon additive are difficult to effectively fuse is effectively solved.

The high-efficiency antibacterial polytetrafluoroethylene microporous membrane prepared by the preparation method contains zinc ions, and has high sterilization rate, broad-spectrum antibacterial property and excellent odor removing capability; the zinc is colorless and tasteless, and does not change the primary color of the product; the zinc is an essential element for human body, and is safe and free of side effect. The antibacterial polytetrafluoroethylene microporous membrane manufactured by the method can be used in the fields of personal protection, air filtration, medical materials and the like.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a 5000-fold electron micrograph of a microporous membrane;

FIG. 2 is a 30000 times electron micrograph of a microporous membrane.

Detailed Description

A preparation method of a high-efficiency antibacterial polytetrafluoroethylene microporous membrane comprises a raw material preparation process and a film forming process.

The preparation process of the raw materials comprises the following steps:

s11, adding 1-10 parts by weight of zinc ion antibacterial agent into 100 parts by weight of absolute ethyl alcohol, mixing and stirring to obtain a mixture A, wherein the stirring time is 30-60 minutes, and the stirring speed is 1000-1500 r/min.

S12, adding 5-15 parts by weight of the mixture A into 100 parts by weight of a hydrocarbon additive to obtain a mixture B; the stirring time is 5-20 minutes, and the stirring speed is 500-.

Wherein the hydrocarbon additive comprises one or more of isoparaffin, petroleum ether, solvent oil and paraffin oil.

If the zinc ion antibacterial agent is directly added into the hydrocarbon additive, the zinc ion antibacterial agent is directly precipitated and cannot be uniformly mixed with the hydrocarbon additive, and the mixture in the state is added into the PTFE resin, so that the metal zinc ion antibacterial agent is unevenly distributed. The zinc ion antibacterial agent and absolute ethyl alcohol are mixed in advance, and then the mixture is added into PTFE dispersion resin powder, so that the distribution uniformity is good.

S13, screening PTFE dispersion resin powder with a 30-mesh screen (pore size of about 590 μm), and filtering out larger particles;

adding the screened PTFE dispersion resin powder into the mixture B, wherein the weight ratio of the PTFE dispersion resin powder to the mixture B is 100: 15-25; stirring to obtain uniform paste material.

And after stirring the PTFE dispersed resin powder and the mixture B, standing for 24 hours at 40-60 ℃ to fully mix the PTFE dispersed resin powder and the mixture B, so that low crosslinking is formed between the PTFE dispersed resin powder and the mixture B, the resin viscosity is reduced, and the PTFE dispersed resin powder and the mixture B are easily extruded.

The film forming process comprises the following steps:

s21, blank making:

filling the paste raw materials into a blank barrel of a briquetting machine, controlling the descending speed of a plunger to be less than 75 mm/min and the pressure to be about 2-5 MPa, and repeatedly pressing for 15-30 min at 40-60 ℃; under the action of shearing force, the spherical material particles are stretched into a fibrous structure, and the air existing among PTFE dispersion resin particles during the mixing of the additive is removed, so that a blank is prepared.

S22, press molding:

the cylindrical blank is placed on a pushing press, and pushed at 40-60 ℃ to form a round bar with the diameter of 10-20 mm, and the round bar is kept in a water tank at 45-60 ℃.

S23, rolling:

fishing out the round strip from the water tank, placing the round strip on a calender, and applying pressure of 5-9 MPa at 50-60 ℃ to prepare a film-shaped coil material with the thickness of 0.1-0.3 mm, so that the subsequent stretching is facilitated; the aperture of the calendered film is small, and the porosity is 25% -30%.

S24, removing hydrocarbon additives:

and (3) placing the rolled film coil material in a closed oven, and placing for 30-60 min at 200-260 ℃ to remove the hydrocarbon additives.

S25, stretching to form a film:

firstly, longitudinal stretching:

and (3) longitudinally stretching the film-shaped coil material without the hydrocarbon additives for the first time at the temperature of 180-260 ℃, namely stretching the film-shaped coil material along the direction parallel to the rolling direction of the film-shaped coil material to obtain a base band, wherein PTFE in the base band exists in a microfibril structure to form a plurality of tiny pores, and the porosity reaches 25-96%.

And (3) secondary biaxial stretching:

and (3) placing the base band on a biaxial stretching machine, and simultaneously carrying out longitudinal stretching and transverse stretching at the temperature of 150-280 ℃ to form the microporous membrane with the width of 1.5-2.5 m and the thickness of 5-30 mu m.

S26, solidifying and sintering:

sintering and curing the stretched microporous membrane at 300-380 ℃ to reduce the crystallinity of the polytetrafluoroethylene membrane and increase the amorphous area, thereby completing amorphous chain cross;

and then rolling to obtain the high-efficiency antibacterial polytetrafluoroethylene microporous membrane containing zinc ions.

An efficient antibacterial polytetrafluoroethylene microporous membrane is prepared by the method.

The high-efficiency antibacterial polytetrafluoroethylene microporous membrane containing zinc ions has the remarkable advantages of uniform distribution of the zinc ions in the microporous membrane and high sterilization rate.

As can be seen from the fig. 1 and 2, the zinc ions on the fiber are not accumulated and are uniformly distributed, and the gaps of the microporous membrane are uniform, so that the bacterial virus can be effectively intercepted.

The antibacterial experiment of the high-efficiency antibacterial polytetrafluoroethylene microporous membrane comprises the following steps:

the test method comprises the following steps: GB/T21510-; the contact time was 24H.

Table one is test data of the antibacterial rate of the wide detection group;

test report number: GTTC 210124086.

Watch 1

Test result analysis shows that the polytetrafluoroethylene microporous membrane obtained by the preparation method has an antibacterial rate of more than 99% on gram-positive bacteria representative staphylococcus aureus and an antibacterial rate of more than 99% on gram-negative bacteria representative escherichia coli.

Ultraviolet aging test of the high-efficiency antibacterial polytetrafluoroethylene microporous membrane:

the test method comprises the following steps: according to the high requirement test condition 4 of GB/T31899 ultraviolet light exposure for textile weather resistance test: the ultraviolet light with irradiance of 0.71W/square meter at 310nm is used for exposure for 4h under the condition that the temperature of a blackboard is 60 ℃, and then the ultraviolet light is condensed for 4h under the condition that the temperature of the blackboard is 50 ℃, so that the cycle is one cycle, and the test is carried out for 5 cycles in total.

Test samples:

sample 1 is a commercially available polytetrafluoroethylene microporous membrane of 0.01mm white nanosilver antimicrobial;

sample 2 is a 0.01mm white nano zinc antimicrobial ptfe microporous membrane made according to the method described above.

Watch two

And the second table is ultraviolet aging test comparison.

The comparison test result analysis shows that the polytetrafluoroethylene microporous membrane prepared by the preparation method has no obvious change in visual color after the experiment, and has excellent ultraviolet aging resistance.

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.