CN109621737A - The preparation method of the PTFE/PFA composite membrane of high porosity - Google Patents
The preparation method of the PTFE/PFA composite membrane of high porosity Download PDFInfo
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- CN109621737A CN109621737A CN201910012517.5A CN201910012517A CN109621737A CN 109621737 A CN109621737 A CN 109621737A CN 201910012517 A CN201910012517 A CN 201910012517A CN 109621737 A CN109621737 A CN 109621737A
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- ptfe
- pfa
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
- B01D71/06—Organic material
- B01D71/30—Polyalkenyl halides
- B01D71/32—Polyalkenyl halides containing fluorine atoms
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
- B01D67/0002—Organic membrane manufacture
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
- B01D69/12—Composite membranes; Ultra-thin membranes
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- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
Abstract
The present invention discloses a kind of preparation method of the PTFE/PFA composite membrane of high porosity.After PTFE resin and PFA resin (mass fraction 0%-30%) and auxiliary agent oil homogeneous blend, through base, squeezes out, roll, dry, longitudinal stretching and cross directional stretch, sintering sizing.Preparation method of the invention is simple, and cost is relatively low, is suitable for mass production.The micropore average pore size of prepared PTFE/PFA composite membrane is 0.2-8 μm, porosity 80-92%, and under 5.3cm/s flow velocity, resistance is 30-120Pa, particle capture efficiency 90%-99.9% when gas containing 0.1-0.3 μm of particle penetrates, can apply in multiple fields such as industrial dedusting, air filtration, liquid filtrations.
Description
Technical field
The present invention relates to a kind of preparation methods of PTFE, PFA composite membrane, more particularly to the PTFE composite film of high porosity
Preparation method.
Background technique
Polytetrafluoroethylene (PTFE) (PTFE) is known as " kings of plastics ", has many excellent performances.And PTFE film surface light
Cunning, does not condense, easy-to-clean ash, does not change porosity after deashing, and its splendid high-low temperature resistant and chemical stability are in treating flour dust
It is widely used in field.
PFA is the copolymer of a small amount of perfluoro propyl perfluoroalkyl vinyl ether and tetrafluoroethene, and performance is quite similar with PTFE,
Also have excellent chemical stability, resistant of high or low temperature and moulding processability good, creep resistance and compressive strength compare PTFE
Good and tensile strength is high.
To guarantee that filtration resistance is maintained at higher water in lower horizontal and processing throughput always in dust removal device
Flat, this just needs to prepare the PTFE film of lower resistance high filtration rate, thin with high porosity but thickness, intensity is low, is unfavorable for
It is laminating with other materials.The present invention mainly by the way that PFA is added to the method in PTFE resin, prepares high porosity, low-resistance
Power and PTFE/PFA composite membrane compared with filtration efficiency.
Summary of the invention
High porosity is prepared technical problem to be solved by the invention is to provide one kind, lower resistance and compared with filtration efficiency
PTFE/PFA composite membrane method, reduce device operation energy consumption.
For the technical problem more than solving, the present invention provides the preparation method of the PTFE/PFA composite membrane of high porosity such as
It is lower described.
(1) it is blended: auxiliary agent oil is stirred at room temperature according to a certain percentage with PTFE resin and PFA resin and mix
It is even, it is cured 24 hours or more in 50 DEG C of constant temperature oven, forms PTFE/PFA mixed material；
(2) the PTFE/PFA mixed material of the curing base: is suppressed into pillared shape base on harder；
(3) squeeze out: the shape base is squeezed out through extruder at 50 °C club be placed in it is quiet in 45 DEG C of water-bath
It sets 5 minutes；
(4) roll: the club is rolled into PTFE/PFA base band, width 12- through calender at 50 DEG C
19cm, with a thickness of 70 μm -200 μm；
(5) dry: PTFE/PFA base band being dried in 180 DEG C of baking oven, removes auxiliary agent oil；
(6) longitudinal stretching and cross directional stretch: the longitudinal drawing of at a temperature of progress by the PTFE/PFA base band at 200-300 DEG C
It stretches, stretching ratio 4-15B, degreasing base band is prepared in processing, then degreasing base band is carried out to lateral expanding at a temperature of 170-220 DEG C
It stretches, stretching ratio 30-50B；
(7) sintering sizing: film after stretching horizontally is sintered to sizing 30-60 seconds at a temperature of 340-370 DEG C, obtains thickness
For 2-5 μm of PTFE/PFA composite membrane；
Preferably, the PFA resin is the MP102 of Japanese E.I.Du Pont Company's production.
Preferably, the auxiliary agent oil is ISOPAR-M, the quality for the auxiliary agent oil that when blending is added is mixed for PTFE/PFA
Close the 20%-38% of quality of material.
Preferably, the quality of the PFA resin is the 0%-30% of PTFE resin quality.
The beneficial effects of the present invention are:
(1) in above-mentioned technical proposal of the invention, PFA resin is selected to be blended with PTFE resin and is doped modification, it can be with
The intensity for improving PTFE film, improves the glossiness of film surface.
(2) in above-mentioned technical proposal of the invention, select PFA resin to be powdered, performance is similar to PTFE resin, mixes
The stability of the film of miscellaneous modified preparation is good.
(3) the PTFE/PFA composite membrane of above-mentioned technical proposal of the invention preparation can be fitted with one-pass molding, simple process
Close serialization industrial production.
The micropore average pore size for the PTFE/PFA composite membrane that the present invention prepares is 0.2-8 μm, porosity 80-92%, and
Under 5.3cm/s flow velocity, resistance 30-120Pa, the particle capture efficiency when gas containing 0.1-0.3 μm of particle penetrates
90%-99.9%.
Performance test of the present invention: average pore size, porosity are tested according to ASTM-316-86 standard using mercury injection apparatus；Film thickness
HY/T053-2001 standard testing is pressed using calibrator；Resistance and filter efficiency are according to GB/T5453-1997 standard, using ZHF
Filtrate monitor station is tested；The surface of film is by field emission microscopy observation.
Detailed description of the invention
Fig. 1 is the scanning electron microscope (SEM) photograph that the present invention prepares PTFE/PFA composite membrane.
Specific embodiment
For a further understanding of the present invention, the preferred embodiment of the invention is described below with reference to embodiment, still
It should be appreciated that these descriptions are only further explanation the features and advantages of the present invention, rather than to the claims in the present invention
Limitation.
The preparation of PTFE/PFA composite membrane of the invention will be described in further detail below, it is therefore intended that make ability
The application is more clearly understood in the technical staff in domain.
Embodiment one
It is blended: by PTFE resin, PFA resin (for the 10% of PTFE resin quality) and auxiliary agent oil (for PTFE resin and PFA
The 28% of resin gross mass) it is uniformly mixed at room temperature, and cured 24 hours or more in 50 DEG C of constant temperature oven, it is formed
PTFE/PFA mixed material；
Base: the PTFE/PFA mixed material of the curing is suppressed into pillared shape base on harder；
It squeezes out: the shape base being squeezed out through extruder to club is at 50 °C placed in 45 DEG C of water-bath and stand 5
Minute；
Calendering: the club is rolled into PTFE/PFA base band, width 19cm, thickness through calender at 50 DEG C
It is 200 μm；
It is dry: PTFE/PFA base band being dried in 180 DEG C of baking oven, removes auxiliary agent oil；
Longitudinal stretching and cross directional stretch: by the PTFE/PFA base band 220 DEG C at a temperature of carry out longitudinal stretching, stretch
Degreasing base band is prepared in multiplying power 14B, processing, then degreasing base band is carried out lateral expanding at a temperature of 190 DEG C and is stretched, stretching ratio
For 45B；
Sintering sizing: film after stretching horizontally is sintered to sizing 40 seconds at a temperature of 340 DEG C, is obtained with a thickness of 5 μm
PTFE/PFA composite membrane；
By the above method prepare PTFE/PFA composite membrane average pore size be 0.2-8 μm, porosity 80-90% and
Under 5.3cm/s flow velocity, resistance 100-118Pa, the particle capture efficiency 98- when gas containing 0.1-0.3 μm of particle penetrates
99.9%.
Embodiment two
1. being blended: by PTFE resin, PFA resin (for the 20% of PTFE resin quality) and auxiliary agent oil (for PTFE resin and
The 28% of PFA resin gross mass) it is uniformly mixed at room temperature, and cured 24 hours or more in 50 DEG C of constant temperature oven,
Form PTFE/PFA mixed material；
2. base: the PTFE/PFA mixed material of the curing is suppressed pillared shape base on harder；
3. squeezing out: the shape base being squeezed out through extruder to club be at 50 °C placed in 45 DEG C of water-bath and stand
5 minutes；
4. calendering: the club being rolled into PTFE/PFA base band through calender at 50 DEG C, width 19cm is thick
Degree is 200 μm；
5. dry: PTFE/PFA base band being dried in 180 DEG C of baking oven, removes auxiliary agent oil；
6. longitudinal stretching and cross directional stretch: by the PTFE/PFA base band 220 DEG C at a temperature of carry out longitudinal stretching, draw
Multiplying power 14B is stretched, degreasing base band is prepared in processing, then degreasing base band is carried out lateral expanding at a temperature of 190 DEG C and is stretched, and is stretched again
Rate is 45B；
7. sintering sizing: film after stretching horizontally being sintered to sizing 40 seconds at a temperature of 340 DEG C, is obtained with a thickness of 4 μm
PTFE/PFA composite membrane；
By the above method prepare PTFE/PFA composite membrane average pore size be 0.2-8 μm, porosity 80-90% and
Under 5.3cm/s flow velocity, resistance 70-95Pa, the particle capture efficiency 96.2- when gas containing 0.1-0.3 μm of particle penetrates
98.7%.
Embodiment three
1. being blended: by PTFE resin, PFA resin (for the 30% of PTFE resin quality) and auxiliary agent oil (for PTFE resin and
The 28% of PFA resin gross mass) it is uniformly mixed at room temperature, and cured 24 hours or more in 50 DEG C of constant temperature oven,
Form PTFE/PFA mixed material；
2. base: the PTFE/PFA mixed material of the curing is suppressed pillared shape base on harder；
3. squeezing out: the shape base being squeezed out through extruder to club be at 50 °C placed in 45 DEG C of water-bath and stand
5 minutes；
4. calendering: the club being rolled into PTFE/PFA base band through calender at 50 DEG C, width 17cm is thick
Degree is 200 μm；
5. dry: PTFE/PFA base band being dried in 180 DEG C of baking oven, removes auxiliary agent oil；
6. longitudinal stretching and cross directional stretch: by the PTFE/PFA base band 220 DEG C at a temperature of carry out longitudinal stretching, draw
Multiplying power 14B is stretched, degreasing base band is prepared in processing, then degreasing base band is carried out lateral expanding at a temperature of 190 DEG C and is stretched, and is stretched again
Rate is 45B；
7. sintering sizing: film after stretching horizontally being sintered to sizing 35 seconds at a temperature of 340 DEG C, is obtained with a thickness of 4 μm
PTFE/PFA composite membrane；
By the above method prepare PTFE/PFA composite membrane average pore size be 0.2-8 μm, porosity 80-91% and
Under 5.3cm/s flow velocity, resistance 50-67Pa, the particle capture efficiency 94- when gas containing 0.1-0.3 μm of particle penetrates
97.4%.
Example IV
1. being blended: by PTFE resin, PFA resin (for the 30% of PTFE resin quality) and auxiliary agent oil (for PTFE resin and
The 30% of PFA resin gross mass) it is uniformly mixed at room temperature, and cured 24 hours or more in 50 DEG C of constant temperature oven,
Form PTFE/PFA mixed material；
2. base: the PTFE/PFA mixed material of the curing is suppressed pillared shape base on harder；
3. squeezing out: the shape base being squeezed out through extruder to club be at 50 °C placed in 45 DEG C of water-bath and stand
5 minutes；
4. calendering: the club is rolled into PTFE/PFA base band through calender at 50 DEG C, width 16.5cm,
With a thickness of 180 μm；
5. dry: PTFE/PFA base band being dried in 180 DEG C of baking oven, removes auxiliary agent oil；
6. longitudinal stretching and cross directional stretch: by the PTFE/PFA base band 220 DEG C at a temperature of carry out longitudinal stretching, draw
Multiplying power 14B is stretched, degreasing base band is prepared in processing, then degreasing base band is carried out lateral expanding at a temperature of 190 DEG C and is stretched, and is stretched again
Rate is 45B；
7. sintering sizing: film after stretching horizontally being sintered to sizing 30 seconds at a temperature of 340 DEG C, is obtained with a thickness of 3 μm
PTFE/PFA composite membrane；
By the above method prepare PTFE/PFA composite membrane average pore size be 0.2-8 μm, porosity 80-92% and
Under 5.3cm/s flow velocity, resistance 30-40Pa, the particle capture efficiency 92- when gas containing 0.1-0.3 μm of particle penetrates
94.5%.
The above description of the embodiment is only used to help understand the method for the present invention and its core ideas.It should be pointed out that pair
For those skilled in the art, without departing from the principle of the present invention, the present invention can also be carried out
Some improvements and modifications, these improvements and modifications also fall within the scope of protection of the claims of the present invention.
Claims (4)
1. a kind of preparation method of the PTFE/PFA composite membrane of high porosity, it is characterised in that: the PTFE/PFA composite membrane
Preparation the following steps are included:
(1) it is blended: auxiliary agent oil is stirred and is uniformly mixed at room temperature according to a certain percentage with PTFE resin and PFA resin,
It is cured 24 hours or more in 50 DEG C of constant temperature oven, forms PTFE/PFA mixed material；
(2) the PTFE/PFA mixed material of the curing base: is suppressed into pillared shape base on harder；
(3) it squeezes out: the shape base being squeezed out through extruder to club is at 50 °C placed in 45 DEG C of water-bath and stand 5 points
Clock；
(4) roll: the club being rolled into PTFE/PFA base band through calender at 50 DEG C, width 12-19cm is thick
Degree is 70 μm -200 μm；
(5) dry: PTFE/PFA base band being dried in 180 DEG C of baking oven, removes auxiliary agent oil；
(6) longitudinal stretching and cross directional stretch: by the PTFE/PFA base band 200-300 DEG C at a temperature of carry out longitudinal stretching,
Degreasing base band is prepared in stretching ratio 4-15B, processing, then degreasing base band is carried out lateral expanding at a temperature of 170-220 DEG C and is drawn
It stretches, stretching ratio 30-50B；
(7) sintering sizing: film after stretching horizontally is sintered to sizing 30-60 seconds at a temperature of 340-370 DEG C, is obtained with a thickness of 2-
5 μm of PTFE/PFA composite membrane.
2. the preparation method of the PTFE/PFA composite membrane of high porosity according to claim 1, it is characterised in that: described to help
The mass fraction of PTFE/PFA mixed material shared by agent oil is 20%-38%.
3. the preparation method of the PTFE/PFA composite membrane of high porosity according to claim 1, it is characterised in that: described
The quality of PFA resin is the 0%-30% of PTFE resin quality.
4. the preparation method of the PTFE/PFA composite membrane of high porosity according to claim 1, it is characterised in that: PTFE/
The micropore average pore size of PFA composite membrane is 0.2-8 μm, porosity 80-92%, and under 5.3cm/s flow velocity, resistance 30-
120Pa, the particle capture efficiency 90%-99.9% when gas containing 0.1-0.3 μm of particle penetrates.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111408284A (en) * | 2020-04-14 | 2020-07-14 | 自然资源部天津海水淡化与综合利用研究所 | A kind of polytetrafluoroethylene microporous membrane and preparation method thereof |
| CN111627606A (en) * | 2020-05-25 | 2020-09-04 | 浙江德通科技有限公司 | High-flame-retardancy coaxial radio frequency cable and preparation method thereof |
| CN112844073A (en) * | 2020-12-31 | 2021-05-28 | 南京玻璃纤维研究设计院有限公司 | Polytetrafluoroethylene composite membrane with three-dimensional supporting structure |
| CN115008780A (en) * | 2022-06-16 | 2022-09-06 | 安徽元琛环保科技股份有限公司 | A kind of preparation method of high-adhesion PTFE rubber strip |
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