HG/T 2901-1997 Test method for particle size of polytetrafluoroethylene resin
Some standard content:
HG/T 2901--.1997
This standard is equivalent to 13.3~~13.5 in ASTMD1457:1992 "Standard Specification for Polytetrafluoroethylene Molding and Extrusion Materials". The main differences between this standard and ASTMD1457 are: (1) Reagents: Considering the high toxicity of perfluoroethylene, this standard recommends the use of 95% ethanol instead of perfluoroethylene as the spray liquid. (2) Sieve: Based on the sieve aperture proposed in ASTMD1457, this standard selects a domestic standard series of sieves with apertures that are similar or close.
(3) Drying time: Since this standard uses 95% ethanol instead of perfluoroethylene as the spray liquid, this standard appropriately extends the drying time of the resin in the wet sieving method and the sieve retention number. (4) Since the particle size of domestic resins similar to type 1 resin (particle size of about 375μm) in ASTMD1457 is about 180μm, considering the versatility of sieves and the influence of changing the aperture on the test results, this standard has revised the sieves recommended by ASTMD1457 and selected sieves with appropriate apertures.
(5) The instrument for placing the sample in the dry sieving method has been changed from "aluminum plate" to "plastic bottle". The previous version of this standard is GB7137-86 "Test method for particle size of polytetrafluoroethylene resin". Compared with the previous version, in addition to adding "Foreword" and "Scope" and introducing Appendix B into the main text of the standard, necessary revisions and supplements have been made to a few technical contents: 1) This standard has revised the scope of application of the wet sieving method, that is, the wet sieving method is applicable to suspended polytetrafluoroethylene resin 2) The weighing of sieves (including sieves filled with resin) in this standard adopts the method of weighing directly on the balance. 3) The "test report" of the wet screening method is no longer required to provide a "corresponding graph of cumulative percentage and sieve hole diameter". Appendix A of this standard is the appendix of the standard.
From the date of implementation of this standard, the original national standard GB7137--86 "Test method for particle size of polytetrafluoroethylene resin" shall be abolished. This standard is proposed by the Technical Supervision Department of the Ministry of Chemical Industry of the People's Republic of China. This standard is under the jurisdiction of the Plastic Tree Product Sub-Technical Committee (SC4) of the National Plastic Standardization Technical Committee. The responsible drafting unit of this standard: Shanghai San Ai Fu New Materials Co., Ltd. The main drafters of this standard: Ma Yujin and Zhou Xiabao. 913
1 Scope
Chemical Industry Standards of the People's Republic of China
Testing method for particle size ofpolytetrafluoroethylene resin
Testing method for particle size ofpolytetrafluoroethylene resinThis standard specifies the test method for particle size of polytetrafluoroethylene resin. HG/T 2901-1997
Replaces GB7137-86
This standard applies to the determination of particle size of polytetrafluoroethylene resin produced by dispersion or suspension polymerization, expressed as average particle size. 2 Definitions
This standard adopts the following definitions:
Average particle size (d) average particle diameter (a) For a certain mass of resin, after sieving, the diameter ds of the particles corresponding to the cumulative mass percentage on each sieve of 50% is called the average particle size (d) of the resin
3 Test method
The particle size of polytetrafluoroethylene resin polymerized by suspension or dispersion polymerization can be determined by wet sieving method and dry sieving method respectively. 3.1 Mixed sieving method
This method is applicable to the determination of particle size of polytetrafluoroethylene resin produced by suspension polymerization. For polytetrafluoroethylene resin with a particle size less than 100μm, it is recommended to measure according to Appendix A "Test method for retention number on 65μm sieve". 3.1.1 Principle of the method
The average particle size and agglomerate size of polytetrafluoroethylene resin are determined by classifying the material with a set of sieves. Before classification, spray and sieve with 95% ethanol to break up agglomerates and prevent clogging of the sieve holes. 3.1.2 Reagent 1
95% ethanol.
3.1.3 Instruments and apparatus
3.1.3.1 Sieve 2: 200 mm in diameter, with apertures of 1440, 1000, 710, 500, 355, 250, 180, 154, 125, 90.76, 65, 55, 45.38.5 μm
3.1.3.2 Balance: sensitivity 0.1 g.
3.1.3.3 Fume hood.
Instructions for use:
1) ASTM D 1457 stipulates perfluoroethylene, but other liquids can also be used. 2] ASTMD1457 stipulates the American standard series of sieves, that is, the diameter is 203mm, and the apertures are 1400, 1000.710, 500, 355, 250, 180, 125, 90, 75, 63, 53, 45.38μm.
Approved by the Ministry of Chemical Industry of the People's Republic of China on May 23, 1997 914
Implementation on October 1, 1997
HG/T2901-1997
3.1.3.4 Screening and spraying device: as shown in Figure 1. The screening and spraying device must be installed in a fume hood or a place with proper exhaust. The components of the device are as follows:
1 Receiver; 2 Sample separation screen group 3-Spray head; 4-Flow meter; 5-Pump; 6-Container Figure 1 Schematic diagram of the spray device
1) Receiver: As shown in Figure 2, the material is a hard polyvinyl chloride plate. $460
$10×346 holes are evenly distributed
Receiver
DY25 elbow
HG/T2901—1997
2) Spray head: As shown in Figure 3, the material is a hard polyvinyl chloride plate. $65
Figure 3 Spray head
3) Flow meter: flow rate 600L/h.
4) Centrifugal pump or other delivery pump.
5) Container: volume 25L.
3.1.3.5 Stopwatch
3.1.4 Operation steps
$×37 holes evenly distributed
3.1.4.1 According to the type of resin to be tested, select a set of matching recommended sieves from Table 1 and weigh them separately (accurate to 0.1g). Record the mass m of each sieve and arrange them from top to bottom in the order listed in Table 1. 916
Sieve aperture
Resin model
(mesh number)
1440(14)
1000(18)
710(26)
500(35)
355(50)
250(65)
180(85)
154(100)
125(1 20)
90(180)
76(200)
65(220)
55(280)
45(320)
38.5(400)
Sampling volume
HG/T 2901—1997
Recommended sieves for various types of polytetrafluoroethylene resinsTable 1
PTFEDE141
PTFESM031\
PTFE DE241
PTFE DE341
PTFE SM021
Select the sampling amount from Table 2, and place it on the top sieve after weighing. Table 2 Sampling amount of various types of polytetrafluoroethylene resinsResin model
PTFE SM031
PTFEDE141
PTFE DE241
PTFE DE341
PTFE SM021
PTFE SM042
PTFESM043
PTFE SM052
PTFE SM053
-PTFE SM042
PTFESM043
PTFESM052
PTFE SM053
PTFE SE041
PTFE SE042
PTFESE043
PTFE SE041
PTFE SE042
PTFE SE043
3.1.4.3 Spray with 95% ethanol at a flow rate of (6±0.5) L/min for 1min±0.2min (if overflow occurs, it can be completed in 2~3 times). The height of the nozzle should be flush with the top of the sieve, and the nozzle should be moved to spray in a circular shape, carefully breaking up all the lumps and washing the resin on the edge of the sieve. 3.1.4.4 Remove the top sieve and place it in a fume hood to dry. 3.1.4.5 Repeat 3.1.4.3 and 3.1.4.4 test steps until all sieves have been sprayed. Dry all sieves in a 90℃ oven for 30min, then take them out, cool them to room temperature and weigh them, accurate to ±0.1g. 3.1.4.6 Record the mass m2 of each sieve with resin. 3.1.4.7 Filter the circulating 95% ethanol with a sieve with a mesh of 38.5um to prevent the resin from entering the circulating liquid. Finally, put the 95% ethanol into a container for precipitation and take the clear liquid for use.
Instructions for use:
3) The recommended sieves for this type of resin in ASTMD1457 have apertures of 1400, 1000, 710, 500, 355, 250, and 180um respectively. 4) ASTMD1457 stipulates that the drying time is 15min. 917
3.1.5 Result Expression
HG/T 29011997
3.1.5.1 Calculate the mass percentage of resin on each sieve according to formula (1): (m2-m,)i
Wherein, Q*-mass percentage of resin on each sieve, %; m2
mass of sieve filled with resin,;
mass of sieve, g;
mass of sample, g.
3.1.5.2 Calculate the cumulative percentage of resin on each sieve according to formula (2): Ci-
Wherein-cumulative percentage of resin on each sieve, %, n
number of sieves.
$+++++++++ (2)
3.1.5.3 On the logarithmic probability coordinate paper, plot the corresponding points of the sieve diameter and the cumulative percentage, and draw a best straight line through these points (as shown in Figure 4). The particle size dso corresponding to the cumulative percentage of 50% is taken as the average particle size a of the resin: adso
3.1.6 Relative standard deviation
Percentage
Cumulative percentage
808590
Figure 4 Relationship between cumulative percentage and sieve diameter
Since the resin has various complex shapes and each sieve has a particle size distribution, the obtained particle size and its distribution are only relative values. The relative standard deviation of the average particle size is ±2.8%. 3.1.7 Test report
The test report shall include the following contents:
a) Sample model and batch number;
b) Sampling date;
c) Mass percentage and cumulative percentage of resin on each sieve;
d) Average particle size value;
e) Test date and test personnel.
3.2 Dry sieving method
HG/T 2901—1997
This method is applicable to the particle size determination of dispersed polytetrafluoroethylene resin. 3.2.1 Principle of the method
Use a group of sieves to grade and sieve to determine the particle size of dispersed polytetrafluoroethylene resin. Use mechanical sac movement to grade and sieve the resin in a predetermined time.
3.2.2 Instruments and devices
Balance: Sensitivity 0.1g.
3.2.2.2 Sieve s): diameter 200mm, aperture 1440, 1000, 710, 500, 355, 250, 180μm. 3.2.2.3 Electric vibrating sieve machine
Motor power: 90W.
Motor speed: 1400r/min;
Number of sieve layers: 7 layers.
3.2.2.4 Refrigerator: household refrigerator.
3.2.2.5 Plastic bottle), 500mL.
3.2.3 Test conditions
The dew point temperature in the test room is lower than the refrigerator temperature. 3.2.4 Operation steps
3.2.4.1 Place the sample in a plastic bottle and place it in a refrigerator below 10℃ for 24h. 3.2.4.2 According to the type of resin to be tested, select matching sieves from Table 1 and weigh them respectively (accurate to 0.1g). Record the mass ml of each sieve and arrange them from top to bottom in the order of Table 1. 3.2.4.3 Select the sample amount from Table 2 and weigh it (accurate to 0.1g). 3.2.4.4 Place the sample in the top sieve and vibrate for 10 minutes, weigh the mass of the sieves with resin left, and record the mass m2 of each sieve with resin left.
3.2.5 Expression of results and test report
The calculation method and test report are the same as those of the wet sieving method (see 3.1.5, 3.1.7). Instructions for use:
5] ASTMD1457 stipulates the American standard series of sieves, that is, the diameter is 203mm, and the apertures are 1400, 1000, 710, 500.335, 250, 180μm. 6】ASTMD1457 stipulates that it is an aluminum pan.
A1 Scope
HG/T2901—1997
Appendix A
(Standard Appendix)
65um sieve retention test method
This appendix is applicable to polytetrafluoroethylene resin with a particle size of less than 100μm. For the determination of particle size distribution, except for using only three sieves, the other methods are similar to the wet sieving method.
A2 Principle of the method
The resin is sieved with a 65μm\ sieve, and 95% ethanol 8 is sprayed during sieving to break up the material clumps and prevent the sieve holes from being blocked. A3 Reagents
95% ethanol 8.
A4 Instruments and devices
A4.1 Sieve 9)
The diameter is 200mm, and the apertures are 900, 65, and 45μm. A4.2 Balance
Sensitivity: 0.01g.
A4.3 Fume hood, sieving and spraying device
See 3.1.3.3 and 3.1.3.4.
A4.4 Stopwatch
A5 Operation steps
A5.1 Weighing
A5.1.1 Weigh the mass (m1) of the 65μm sieve on the balance (accurate to 0.01g). A5.1.2 Arrange the sieves from top to bottom in order of mesh size from large to small. A5.1.3 Weigh 10g of the sample (accurate to 0.01g) and place it in the top sieve. A5.2 Spraying
A5.2.1 Adjust the flow rate of 95% ethanol to (6±0.5)L/min. Aim at the 900μm sieve and spray for 1 minute, move the nozzle in a circular motion, carefully break up all the lumps, and rinse the resin on the side of the sieve. A5.2.2 Remove the 900μm sieve (replace the 45μm sieve with a clean sieve of the same aperture), and spray for 6 minutes on the 65um sieve.
A5.3 Drying and weighing
Dry the 65μm sieve in a fume hood for 15 minutes, then put it in an oven and dry it at 90℃ for 30 minutes1. Weigh the mass (m) of the sieve and the resin, and weigh it to 0.01g.
Instructions for use:
7) ASTMD1457 stipulates a 63um sieve.
8] ASTM D 1457 stipulates perchloroethylene, but other liquids can also be used. 9】ASTMD1457 stipulates the American standard series sieves, that is, the diameter is 203mm, and the apertures are 850, 63, and 45μm. 10］ASTMD1457 stipulates that the 63μm sieve is directly placed in an oven at 80℃～120℃ for more than 20 minutes". 920
A5.4 Filtration
HG/T 2901—1997
Filter the circulating 95% ethanol with a sieve with a mesh of 38.5μm to prevent the resin from entering the circulating liquid. Finally, put the 95% ethanol into a container for precipitation and take the clear liquid for use.
A6 Result display
A6.1 65μm sieve resin retention amount
Calculate the 65μm sieve resin retention amount m according to (A1): m=mz
65μm sieve resin retention amount, g;
Where: m-—
m2 --The mass of the 65um sieve with resin, g3ml---The mass of the 65μm sieve, g.
A6.2Retention percentage of resin on 65μm sieve
Calculate the retention percentage of resin on 65μm sieve according to formula (A2): R
Where: R—
Retention percentage of resin on 65um sieve, %,
Retention amount of resin on 65um sieve, gs
M——Mass of sample, g.
Test report
The test report should include the following contents:
a) Sample model and batch number;
b) Sampling date,
c) Retention amount of resin on 65μm sieve;
d) Retention percentage of resin on 65μm sieve; e) Test date and test personnel.Filter the circulating 95% ethanol with a 5um sieve to prevent the resin from entering the circulating liquid. Finally, put the 95% ethanol into a container for precipitation and take the clear liquid for use.
Instructions for use:
3) The recommended sieves for this type of resin in ASTMD1457 have apertures of 1400, 1000, 710, 500, 355, 250, and 180um respectively. 4) ASTMD1457 stipulates that the drying time is 15min. 917
3.1.5 Result Expression
HG/T 29011997
3.1.5.1 Calculate the mass percentage of resin on each sieve according to formula (1): (m2-m,)i
Wherein, Q*-mass percentage of resin on each sieve, %; m2
mass of sieve filled with resin,;
mass of sieve, g;
mass of sample, g.
3.1.5.2 Calculate the cumulative percentage of resin on each sieve according to formula (2): Ci-
Wherein-cumulative percentage of resin on each sieve, %, n
number of sieves.
$+++++++++ (2)
3.1.5.3 On the logarithmic probability coordinate paper, plot the corresponding points of the sieve diameter and the cumulative percentage, and draw a best straight line through these points (as shown in Figure 4). The particle size dso corresponding to the cumulative percentage of 50% is taken as the average particle size a of the resin: adso
3.1.6 Relative standard deviation
Percentage
Cumulative percentage
808590
Figure 4 Relationship between cumulative percentage and sieve diameter
Since the resin has various complex shapes and each sieve has a particle size distribution, the obtained particle size and its distribution are only relative values. The relative standard deviation of the average particle size is ±2.8%. 3.1.7 Test report
The test report shall include the following contents:
a) Sample model and batch number;
b) Sampling date;
c) Mass percentage and cumulative percentage of resin on each sieve;
d) Average particle size value;
e) Test date and test personnel.
3.2 Dry sieving method
HG/T 2901—1997
This method is applicable to the particle size determination of dispersed polytetrafluoroethylene resin. 3.2.1 Principle of the method
Use a group of sieves to grade and sieve to determine the particle size of dispersed polytetrafluoroethylene resin. Use mechanical sac movement to grade and sieve the resin in a predetermined time.
3.2.2 Instruments and devices
Balance: Sensitivity 0.1g.
3.2.2.2 Sieve s): diameter 200mm, aperture 1440, 1000, 710, 500, 355, 250, 180μm. 3.2.2.3 Electric vibrating sieve machine
Motor power: 90W.
Motor speed: 1400r/min;
Number of sieve layers: 7 layers.
3.2.2.4 Refrigerator: household refrigerator.
3.2.2.5 Plastic bottle), 500mL.
3.2.3 Test conditions
The dew point temperature in the test room is lower than the refrigerator temperature. 3.2.4 Operation steps
3.2.4.1 Place the sample in a plastic bottle and place it in a refrigerator below 10℃ for 24h. 3.2.4.2 According to the type of resin to be tested, select matching sieves from Table 1 and weigh them respectively (accurate to 0.1g). Record the mass ml of each sieve and arrange them from top to bottom according to the order of Table 1. 3.2.4.3 Select the sample amount from Table 2 and weigh it (accurate to 0.1g). 3.2.4.4 Place the sample in the top sieve and vibrate for 10 minutes, weigh the mass of the sieves with resin left, and record the mass m2 of each sieve with resin left.
3.2.5 Expression of results and test report
The calculation method and test report are the same as those of the wet sieving method (see 3.1.5, 3.1.7). Instructions for use:
5] ASTMD1457 stipulates the American standard series of sieves, that is, the diameter is 203mm, and the apertures are 1400, 1000, 710, 500.335, 250, 180μm. 6】ASTMD1457 stipulates that it is an aluminum pan.
A1 Scope
HG/T2901—1997
Appendix A
(Standard Appendix)
65um sieve retention test method
This appendix is applicable to polytetrafluoroethylene resin with a particle size of less than 100μm. For the determination of particle size distribution, except for using only three sieves, the other methods are similar to the wet sieving method.
A2 Principle of the method
The resin is sieved with a 65μm\ sieve, and 95% ethanol 8 is sprayed during sieving to break up the material clumps and prevent the sieve holes from being blocked. A3 Reagents
95% ethanol 8.
A4 Instruments and devices
A4.1 Sieve 9)
The diameter is 200mm, and the apertures are 900, 65, and 45μm. A4.2 Balance
Sensitivity: 0.01g.
A4.3 Fume hood, sieving and spraying device
See 3.1.3.3 and 3.1.3.4.
A4.4 Stopwatch
A5 Operation steps
A5.1 Weighing
A5.1.1 Weigh the mass (m1) of the 65μm sieve on the balance (accurate to 0.01g). A5.1.2 Arrange the sieves from top to bottom in order of mesh size from large to small. A5.1.3 Weigh 10g of the sample (accurate to 0.01g) and place it in the top sieve. A5.2 Spraying
A5.2.1 Adjust the flow rate of 95% ethanol to (6±0.5)L/min. Aim at the 900μm mesh and spray for 1 minute, move the nozzle in a circular motion, carefully break up all the lumps, and rinse the resin on the side of the mesh. A5.2.2 Remove the 900μm mesh (replace the 45μm mesh with a clean mesh of the same aperture), and spray for 6 minutes on the 65um mesh.
A5.3 Drying and weighing
Dry the 65μm mesh in a fume hood for 15 minutes, then put it in an oven and dry it at 90℃ for 30 minutes1. Weigh the mass (m) of the mesh and the resin, and weigh it to 0.01g.
Instructions for use:
7) ASTMD1457 stipulates a 63um mesh.
8] ASTM D 1457 stipulates perchloroethylene, but other liquids can also be used. 9】ASTMD1457 stipulates the American standard series sieves, that is, the diameter is 203mm, and the apertures are 850, 63, and 45μm. 10］ASTMD1457 stipulates that the 63μm sieve is directly placed in an oven at 80℃～120℃ for more than 20 minutes". 920
A5.4 Filtration
HG/T 2901—1997
Filter the circulating 95% ethanol with a sieve with a mesh of 38.5μm to prevent the resin from entering the circulating liquid. Finally, place the 95% ethanol in a container for precipitation and take the clear liquid for use.
A6 Result display
A6.1 65μm sieve resin retention amount
Calculate the 65μm sieve resin retention amount m according to (A1): m=mz
65μm sieve resin retention amount, g;
Where: m-—
m2 --The mass of the 65um sieve with resin, g3ml---The mass of the 65μm sieve, g.
A6.2Retention percentage of resin on 65μm sieve
Calculate the retention percentage of resin on 65μm sieve according to formula (A2): R
Where: R—
Retention percentage of resin on 65um sieve, %,
Retention amount of resin on 65um sieve, gs
M——Mass of sample, g.
Test report
The test report should include the following contents:
a) Sample model and batch number;
b) Sampling date,
c) Retention amount of resin on 65μm sieve;
d) Retention percentage of resin on 65μm sieve; e) Test date and test personnel.Filter the circulating 95% ethanol with a 5um sieve to prevent the resin from entering the circulating liquid. Finally, put the 95% ethanol into a container for precipitation and take the clear liquid for use.
Instructions for use:
3) The recommended sieves for this type of resin in ASTMD1457 have apertures of 1400, 1000, 710, 500, 355, 250, and 180um respectively. 4) ASTMD1457 stipulates that the drying time is 15min. 917
3.1.5 Result Expression
HG/T 29011997
3.1.5.1 Calculate the mass percentage of resin on each sieve according to formula (1): (m2-m,)i
Wherein, Q*-mass percentage of resin on each sieve, %; m2
mass of sieve filled with resin,;
mass of sieve, g;
mass of sample, g.
3.1.5.2 Calculate the cumulative percentage of resin on each sieve according to formula (2): Ci-
Wherein-cumulative percentage of resin on each sieve, %, n
number of sieves.
$+++++++++ (2)
3.1.5.3 On the logarithmic probability coordinate paper, plot the corresponding points of the sieve diameter and the cumulative percentage, and draw a best straight line through these points (as shown in Figure 4). The particle size dso corresponding to the cumulative percentage of 50% is taken as the average particle size a of the resin: adso
3.1.6 Relative standard deviation
Percentage
Cumulative percentage
808590
Figure 4 Relationship between cumulative percentage and sieve diameter
Since the resin has various complex shapes and each sieve has a particle size distribution, the obtained particle size and its distribution are only relative values. The relative standard deviation of the average particle size is ±2.8%. 3.1.7 Test report
The test report shall include the following contents:
a) Sample model and batch number;
b) Sampling date;
c) Mass percentage and cumulative percentage of resin on each sieve;
d) Average particle size value;
e) Test date and test personnel.
3.2 Dry sieving method
HG/T 2901—1997
This method is applicable to the particle size determination of dispersed polytetrafluoroethylene resin. 3.2.1 Principle of the method
Use a group of sieves to grade and sieve to determine the particle size of dispersed polytetrafluoroethylene resin. Use mechanical sac movement to grade and sieve the resin in a predetermined time.
3.2.2 Instruments and devices
Balance: Sensitivity 0.1g.
3.2.2.2 Sieve s): diameter 200mm, aperture 1440, 1000, 710, 500, 355, 250, 180μm. 3.2.2.3 Electric vibrating sieve machine
Motor power: 90W.
Motor speed: 1400r/min;
Number of sieve layers: 7 layers.
3.2.2.4 Refrigerator: household refrigerator.
3.2.2.5 Plastic bottle), 500mL.
3.2.3 Test conditions
The dew point temperature in the test room is lower than the refrigerator temperature. 3.2.4 Operation steps
3.2.4.1 Place the sample in a plastic bottle and place it in a refrigerator below 10℃ for 24h. 3.2.4.2 According to the type of resin to be tested, select matching sieves from Table 1 and weigh them respectively (accurate to 0.1g). Record the mass ml of each sieve and arrange them from top to bottom according to the order of Table 1. 3.2.4.3 Select the sample amount from Table 2 and weigh it (accurate to 0.1g). 3.2.4.4 Place the sample in the top sieve and vibrate for 10 minutes, weigh the mass of the sieves with resin left, and record the mass m2 of each sieve with resin left.
3.2.5 Expression of results and test report
The calculation method and test report are the same as those of the wet sieving method (see 3.1.5, 3.1.7). Instructions for use:
5] ASTMD1457 stipulates the American standard series of sieves, that is, the diameter is 203mm, and the apertures are 1400, 1000, 710, 500.335, 250, 180μm. 6】ASTMD1457 stipulates that it is an aluminum pan.
A1 Scope
HG/T2901—1997
Appendix A
(Standard Appendix)
65um sieve retention test method
This appendix is applicable to polytetrafluoroethylene resin with a particle size of less than 100μm. For the determination of particle size distribution, except for using only three sieves, the other methods are similar to the wet sieving method.
A2 Principle of the method
The resin is sieved with a 65μm\ sieve, and 95% ethanol 8 is sprayed during sieving to break up the material clumps and prevent the sieve holes from being blocked. A3 Reagents
95% ethanol 8.
A4 Instruments and devices
A4.1 Sieve 9)
The diameter is 200mm, and the apertures are 900, 65, and 45μm. A4.2 Balance
Sensitivity: 0.01g.
A4.3 Fume hood, sieving and spraying device
See 3.1.3.3 and 3.1.3.4.
A4.4 Stopwatch
A5 Operation steps
A5.1 Weighing
A5.1.1 Weigh the mass (m1) of the 65μm sieve on the balance (accurate to 0.01g). A5.1.2 Arrange the sieves from top to bottom in order of mesh size from large to small. A5.1.3 Weigh 10g of the sample (accurate to 0.01g) and place it in the top sieve. A5.2 Spraying
A5.2.1 Adjust the flow rate of 95% ethanol to (6±0.5)L/min. Aim at the 900μm mesh and spray for 1 minute, move the nozzle in a circular motion, carefully break up all the lumps, and rinse the resin on the side of the mesh. A5.2.2 Remove the 900μm mesh (replace the 45μm mesh with a clean mesh of the same aperture), and spray for 6 minutes on the 65um mesh.
A5.3 Drying and weighing
Dry the 65μm mesh in a fume hood for 15 minutes, then put it in an oven and dry it at 90℃ for 30 minutes1. Weigh the mass (m) of the mesh and the resin, and weigh it to 0.01g.
Instructions for use:
7) ASTMD1457 stipulates a 63um mesh.
8] ASTM D 1457 stipulates perchloroethylene, but other liquids can also be used. 9】ASTMD1457 stipulates the American standard series sieves, that is, the diameter is 203mm, and the apertures are 850, 63, and 45μm. 10］ASTMD1457 stipulates that the 63μm sieve is directly placed in an oven at 80℃～120℃ for more than 20 minutes". 920
A5.4 Filtration
HG/T 2901—1997
Filter the circulating 95% ethanol with a sieve with a mesh of 38.5μm to prevent the resin from entering the circulating liquid. Finally, place the 95% ethanol in a container for precipitation and take the clear liquid for use.
A6 Result display
A6.1 65μm sieve resin retention amount
Calculate the 65μm sieve resin retention amount m according to (A1): m=mz
65μm sieve resin retention amount, g;
Where: m-—
m2 --The mass of the 65um sieve with resin, g3ml---The mass of the 65μm sieve, g.
A6.2Retention percentage of resin on 65μm sieve
Calculate the retention percentage of resin on 65μm sieve according to formula (A2): R
Where: R—
Retention percentage of resin on 65um sieve, %,www.bzxz.net
Retention amount of resin on 65um sieve, gs
M——Mass of sample, g.
Test report
The test report should include the following contents:
a) Sample model and batch number;
b) Sampling date,
c) Retention amount of resin on 65μm sieve;
d) Retention percentage of resin on 65μm sieve; e) Test date and test personnel.)i
wherein Q*-mass percentage of resin on each sieve, %; m2
mass of sieve filled with resin,;
mass of sieve, g;
mass of sample, g.
3.1.5.2 Calculate the cumulative percentage of resin on each sieve according to formula (2): Ci-
wherein - cumulative percentage of resin on each sieve, %, n
number of sieves.
$+++++++++ (2)
3.1.5.3 On the logarithmic probability coordinate paper, plot the corresponding points of the sieve diameter and the cumulative percentage, and draw a best straight line through these points (as shown in Figure 4). The particle size dso corresponding to the cumulative percentage of 50% is taken as the average particle size a of the resin: adso
3.1.6 Relative standard deviation
Percentage
Cumulative percentage
808590
Figure 4 Relationship between cumulative percentage and sieve diameter
Since the resin has various complex shapes and each sieve has a particle size distribution, the obtained particle size and its distribution are only relative values. The relative standard deviation of the average particle size is ±2.8%. 3.1.7 Test report
The test report shall include the following contents:
a) Sample model and batch number;
b) Sampling date;
c) Mass percentage and cumulative percentage of resin on each sieve;
d) Average particle size value;
e) Test date and test personnel.
3.2 Dry sieving method
HG/T 2901—1997
This method is applicable to the particle size determination of dispersed polytetrafluoroethylene resin. 3.2.1 Principle of the method
Use a group of sieves to grade and sieve to determine the particle size of dispersed polytetrafluoroethylene resin. Use mechanical sac movement to grade and sieve the resin in a predetermined time.
3.2.2 Instruments and devices
Balance: Sensitivity 0.1g.
3.2.2.2 Sieve s): diameter 200mm, aperture 1440, 1000, 710, 500, 355, 250, 180μm. 3.2.2.3 Electric vibrating sieve machine
Motor power: 90W.
Motor speed: 1400r/min;
Number of sieve layers: 7 layers.
3.2.2.4 Refrigerator: household refrigerator.
3.2.2.5 Plastic bottle), 500mL.
3.2.3 Test conditions
The dew point temperature in the test room is lower than the refrigerator temperature. 3.2.4 Operation steps
3.2.4.1 Place the sample in a plastic bottle and place it in a refrigerator below 10℃ for 24h. 3.2.4.2 According to the type of resin to be tested, select matching sieves from Table 1 and weigh them respectively (accurate to 0.1g). Record the mass ml of each sieve and arrange them from top to bottom according to the order of Table 1. 3.2.4.3 Select the sample amount from Table 2 and weigh it (accurate to 0.1g). 3.2.4.4 Place the sample in the top sieve and vibrate for 10 minutes, weigh the mass of the sieves with resin left, and record the mass m2 of each sieve with resin left.
3.2.5 Expression of results and test report
The calculation method and test report are the same as those of the wet sieving method (see 3.1.5, 3.1.7). Instructions for use:
5] ASTMD1457 stipulates the American standard series of sieves, that is, the diameter is 203mm, and the apertures are 1400, 1000, 710, 500.335, 250, 180μm. 6】ASTMD1457 stipulates that it is an aluminum pan.
A1 Scope
HG/T2901—1997
Appendix A
(Standard Appendix)
65um sieve retention test method
This appendix is applicable to polytetrafluoroethylene resin with a particle size of less than 100μm. For the determination of particle size distribution, except for using only three sieves, the other methods are similar to the wet sieving method.
A2 Principle of the method
The resin is sieved with a 65μm\ sieve, and 95% ethanol 8 is sprayed during sieving to break up the material clumps and prevent the sieve holes from being blocked. A3 Reagents
95% ethanol 8.
A4 Instruments and devices
A4.1 Sieve 9)
The diameter is 200mm, and the apertures are 900, 65, and 45μm. A4.2 Balance
Sensitivity: 0.01g.
A4.3 Fume hood, sieving and spraying device
See 3.1.3.3 and 3.1.3.4.
A4.4 Stopwatch
A5 Operation steps
A5.1 Weighing
A5.1.1 Weigh the mass (m1) of the 65μm sieve on the balance (accurate to 0.01g). A5.1.2 Arrange the sieves from top to bottom in order of mesh size from large to small. A5.1.3 Weigh 10g of the sample (accurate to 0.01g) and place it in the top sieve. A5.2 Spraying
A5.2.1 Adjust the flow rate of 95% ethanol to (6±0.5)L/min. Aim at the 900μm sieve and spray for 1 minute, move the nozzle in a circular motion, carefully break up all the lumps, and rinse the resin on the side of the sieve. A5.2.2 Remove the 900μm sieve (replace the 45μm sieve with a clean sieve of the same aperture), and spray for 6 minutes on the 65um sieve.
A5.3 Drying and weighing
Dry the 65μm sieve in a fume hood for 15 minutes, then put it in an oven and dry it at 90℃ for 30 minutes1. Weigh the mass (m) of the sieve and the resin, and weigh it to 0.01g.
Instructions for use:
7) ASTMD1457 stipulates a 63um sieve.
8] ASTM D 1457 stipulates perchloroethylene, but other liquids can also be used. 9】ASTMD1457 stipulates the American standard series sieves, that is, the diameter is 203mm, and the apertures are 850, 63, and 45μm. 10］ASTMD1457 stipulates that the 63μm sieve is directly placed in an oven at 80℃～120℃ for more than 20 minutes". 920
A5.4 Filtration
HG/T 2901—1997
Filter the circulating 95% ethanol with a sieve with a mesh of 38.5μm to prevent the resin from entering the circulating liquid. Finally, put the 95% ethanol into a container for precipitation and take the clear liquid for use.
A6 Result display
A6.1 65μm sieve resin retention amount
Calculate the 65μm sieve resin retention amount m according to (A1): m=mz
65μm sieve resin retention amount, g;
Where: m-—
m2 --The mass of the 65um sieve with resin, g3ml---The mass of the 65μm sieve, g.
A6.2Retention percentage of resin on 65μm sieve
Calculate the retention percentage of resin on 65μm sieve according to formula (A2): R
Where: R—
Retention percentage of resin on 65um sieve, %,
Retention amount of resin on 65um sieve, gs
M——Mass of sample, g.
Test report
The test report should include the following contents:
a) Sample model and batch number;
b) Sampling date,
c) Retention amount of resin on 65μm sieve;
d) Retention percentage of resin on 65μm sieve; e) Test date and test personnel.)i
wherein Q*-mass percentage of resin on each sieve, %; m2
mass of sieve filled with resin,;
mass of sieve, g;
mass of sample, g.
3.1.5.2 Calculate the cumulative percentage of resin on each sieve according to formula (2): Ci-
wherein - cumulative percentage of resin on each sieve, %, n
number of sieves.
$+++++++++ (2)
3.1.5.3 On the logarithmic probability coordinate paper, draw the corresponding points of the sieve diameter and the cumulative percentage, and draw a best straight line through these points (as shown in Figure 4). The particle size dso corresponding to the cumulative percentage of 50% is taken as the average particle size a of the resin: adso
3.1.6 Relative standard deviation
Percentage
Cumulative percentage
808590
Figure 4 Relationship between cumulative percentage and sieve diameter
Since the resin has various complex shapes and each sieve has a particle size distribution, the obtained particle size and its distribution are only relative values. The relative standard deviation of the average particle size is ±2.8%. 3.1.7 Test report
The test report shall include the following contents:
a) Sample model and batch number;
b) Sampling date;
c) Mass percentage and cumulative percentage of resin on each sieve;
d) Average particle size value;
e) Test date and test personnel.
3.2 Dry sieving method
HG/T 2901—1997
This method is applicable to the particle size determination of dispersed polytetrafluoroethylene resin. 3.2.1 Principle of the method
Use a group of sieves to grade and sieve to determine the particle size of dispersed polytetrafluoroethylene resin. Use mechanical sac movement to grade and sieve the resin in a predetermined time.
3.2.2 Instruments and devices
Balance: Sensitivity 0.1g.
3.2.2.2 Sieve s): diameter 200mm, aperture 1440, 1000, 710, 500, 355, 250, 180μm. 3.2.2.3 Electric vibrating sieve machine
Motor power: 90W.
Motor speed: 1400r/min;
Number of sieve layers: 7 layers.
3.2.2.4 Refrigerator: household refrigerator.
3.2.2.5 Plastic bottle), 500mL.
3.2.3 Test conditions
The dew point temperature in the test room is lower than the refrigerator temperature. 3.2.4 Operation steps
3.2.4.1 Place the sample in a plastic bottle and place it in a refrigerator below 10℃ for 24h. 3.2.4.2 According to the type of resin to be tested, select matching sieves from Table 1 and weigh them respectively (accurate to 0.1g). Record the mass ml of each sieve and arrange them from top to bottom in the order of Table 1. 3.2.4.3 Select the sample amount from Table 2 and weigh it (accurate to 0.1g). 3.2.4.4 Place the sample in the top sieve and vibrate for 10 minutes, weigh the mass of the sieves with resin left, and record the mass m2 of each sieve with resin left.
3.2.5 Expression of results and test report
The calculation method and test report are the same as those of the wet sieving method (see 3.1.5, 3.1.7). Instructions for use:
5] ASTMD1457 stipulates the American standard series of sieves, that is, the diameter is 203mm, and the apertures are 1400, 1000, 710, 500.335, 250, 180μm. 6】ASTMD1457 stipulates that it is an aluminum pan.
A1 Scope
HG/T2901—1997
Appendix A
(Standard Appendix)
65um sieve retention test method
This appendix is applicable to polytetrafluoroethylene resin with a particle size of less than 100μm. For the determination of particle size distribution, except for using only three sieves, the other methods are similar to the wet sieving method.
A2 Principle of the method
The resin is sieved with a 65μm\ sieve, and 95% ethanol 8 is sprayed during sieving to break up the material clumps and prevent the sieve holes from being blocked. A3 Reagents
95% ethanol 8.
A4 Instruments and devices
A4.1 Sieve 9)
The diameter is 200mm, and the apertures are 900, 65, and 45μm. A4.2 Balance
Sensitivity: 0.01g.
A4.3 Fume hood, sieving and spraying device
See 3.1.3.3 and 3.1.3.4.
A4.4 Stopwatch
A5 Operation steps
A5.1 Weighing
A5.1.1 Weigh the mass (m1) of the 65μm sieve on the balance (accurate to 0.01g). A5.1.2 Arrange the sieves from top to bottom in order of mesh size from large to small. A5.1.3 Weigh 10g of the sample (accurate to 0.01g) and place it in the top sieve. A5.2 Spraying
A5.2.1 Adjust the flow rate of 95% ethanol to (6±0.5)L/min. Aim at the 900μm sieve and spray for 1 minute, move the nozzle in a circular motion, carefully break up all the lumps, and rinse the resin on the side of the sieve. A5.2.2 Remove the 900μm sieve (replace the 45μm sieve with a clean sieve of the same aperture), and spray for 6 minutes on the 65um sieve.
A5.3 Drying and weighing
Dry the 65μm sieve in a fume hood for 15 minutes, then put it in an oven and dry it at 90℃ for 30 minutes1. Weigh the mass (m) of the sieve and the resin, and weigh it to 0.01g.
Instructions for use:
7) ASTMD1457 stipulates a 63um sieve.
8] ASTM D 1457 stipulates perchloroethylene, but other liquids can also be used. 9】ASTMD1457 stipulates the American standard series sieves, that is, the diameter is 203mm, and the apertures are 850, 63, and 45μm. 10］ASTMD1457 stipulates that the 63μm sieve is directly placed in an oven at 80℃～120℃ for more than 20 minutes". 920
A5.4 Filtration
HG/T 2901—1997
Filter the circulating 95% ethanol with a sieve with a mesh of 38.5μm to prevent the resin from entering the circulating liquid. Finally, put the 95% ethanol into a container for precipitation and take the clear liquid for use.
A6 Result display
A6.1 65μm sieve resin retention amount
Calculate the 65μm sieve resin retention amount m according to (A1): m=mz
65μm sieve resin retention amount, g;
Where: m-—
m2 --The mass of the 65um sieve with resin, g3ml---The mass of the 65μm sieve, g.
A6.2Retention percentage of resin on 65μm sieve
Calculate the retention percentage of resin on 65μm sieve according to formula (A2): R
Where: R—
Retention percentage of resin on 65um sieve, %,
Retention amount of resin on 65um sieve, gs
M——Mass of sample, g.
Test report
The test report should include the following contents:
a) Sample model and batch number;
b) Sampling date,
c) Retention amount of resin on 65μm sieve;
d) Retention percentage of resin on 65μm sieve; e) Test date and test personnel.7 Test report
The test report shall include the following contents:
a) Sample model and batch number;
b) Sampling date;
c) Mass percentage and cumulative percentage of resin on each sieve; d) Average particle size value;
e) Test date and test personnel.
3.2 Dry sieving method
HG/T 2901—1997
This method is applicable to the particle size determination of dispersed polytetrafluoroethylene resin. 3.2.1 Principle of the method
Use a group of sieves to grade and sieve to determine the particle size of dispersed polytetrafluoroethylene resin. Use mechanical sac movement to grade and sieve the resin in a predetermined time.
3.2.2 Instruments and devices
Balance: Sensitivity 0.1g.
3.2.2.2 Sieve s): diameter 200mm, aperture 1440, 1000, 710, 500, 355, 250, 180μm. 3.2.2.3 Electric vibrating sieve machine
Motor power: 90W.
Motor speed: 1400r/min;
Number of sieve layers: 7 layers.
3.2.2.4 Refrigerator: household refrigerator.
3.2.2.5 Plastic bottle), 500mL.
3.2.3 Test conditions
The dew point temperature in the test room is lower than the refrigerator temperature. 3.2.4 Operation steps
3.2.4.1 Place the sample in a plastic bottle and place it in a refrigerator below 10℃ for 24h. 3.2.4.2 According to the type of resin to be tested, select matching sieves from Table 1 and weigh them respectively (accurate to 0.1g). Record the mass ml of each sieve and arrange them from top to bottom according to the order of Table 1. 3.2.4.3 Select the sample amount from Table 2 and weigh it (accurate to 0.1g). 3.2.4.4 Place the sample in the top sieve and vibrate for 10 minutes, weigh the mass of the sieves with resin left, and record the mass m2 of each sieve with resin left.
3.2.5 Expression of results and test report
The calculation method and test report are the same as those of the wet sieving method (see 3.1.5, 3.1.7). Instructions for use:
5] ASTMD1457 stipulates the American standard series of sieves, that is, the diameter is 203mm, and the apertures are 1400, 1000, 710, 500.335, 250, 180μm. 6】ASTMD1457 stipulates that it is an aluminum pan.
A1 Scope
HG/T2901—1997
Appendix A
(Standard Appendix)
65um sieve retention test method
This appendix is applicable to polytetrafluoroethylene resin with a particle size of less than 100μm. For the determination of particle size distribution, except for using only three sieves, the other methods are similar to the wet sieving method.
A2 Principle of the method
The resin is sieved with a 65μm\ sieve, and 95% ethanol 8 is sprayed during sieving to break up the material clumps and prevent the sieve holes from being blocked. A3 Reagents
95% ethanol 8.
A4 Instruments and devices
A4.1 Sieve 9)
The diameter is 200mm, and the apertures are 900, 65, and 45μm. A4.2 Balance
Sensitivity: 0.01g.
A4.3 Fume hood, sieving and spraying device
See 3.1.3.3 and 3.1.3.4.
A4.4 Stopwatch
A5 Operation steps
A5.1 Weighing
A5.1.1 Weigh the mass (m1) of the 65μm sieve on the balance (accurate to 0.01g). A5.1.2 Arrange the sieves from top to bottom in order of mesh size from large to small. A5.1.3 Weigh 10g of the sample (accurate to 0.01g) and place it in the top sieve. A5.2 Spraying
A5.2.1 Adjust the flow rate of 95% ethanol to (6±0.5)L/min. Aim at the 900μm sieve and spray for 1 minute, move the nozzle in a circular motion, carefully break up all the lumps, and rinse the resin on the side of the sieve. A5.2.2 Remove the 900μm sieve (replace the 45μm sieve with a clean sieve of the same aperture), and spray for 6 minutes on the 65um sieve.
A5.3 Drying and weighing
Dry the 65μm sieve in a fume hood for 15 minutes, then put it in an oven and dry it at 90℃ for 30 minutes1. Weigh the mass (m) of the sieve and the resin, and weigh it to 0.01g.
Instructions for use:
7) ASTMD1457 stipulates a 63um sieve.
8] ASTM D 1457 stipulates perchloroethylene, but other liquids can also be used. 9】ASTMD1457 stipulates the American standard series sieves, that is, the diameter is 203mm, and the apertures are 850, 63, and 45μm. 10］ASTMD1457 stipulates that the 63μm sieve is directly placed in an oven at 80℃～120℃ for more than 20 minutes". 920
A5.4 Filtration
HG/T 2901—1997
Filter the circulating 95% ethanol with a sieve with a mesh of 38.5μm to prevent the resin from entering the circulating liquid. Finally, put the 95% ethanol into a container for precipitation and take the clear liquid for use.
A6 Result display
A6.1 65μm sieve resin retention amount
Calculate the 65μm sieve resin retention amount m according to (A1): m=mz
65μm sieve resin retention amount, g;
Where: m-—
m2 --The mass of the 65um sieve with resin, g3ml---The mass of the 65μm sieve, g.
A6.2Retention percentage of resin on 65μm sieve
Calculate the retention percentage of resin on 65μm sieve according to formula (A2): R
Where: R—
Retention percentage of resin on 65um sieve, %,
Retention amount of resin on 65um sieve, gs
M——Mass of sample, g.
Test report
The test report should include the following contents:
a) Sample model and batch number;
b) Sampling date,
c) Retention amount of resin on 65μm sieve;
d) Retention percentage of resin on 65μm sieve; e) Test date and test personnel.7 Test report
The test report shall include the following contents:
a) Sample model and batch number;
b) Sampling date;
c) Mass percentage and cumulative percentage of resin on each sieve; d) Average particle size value;
e) Test date and test personnel.
3.2 Dry sieving method
HG/T 2901—1997
This method is applicable to the particle size determination of dispersed polytetrafluoroethylene resin. 3.2.1 Principle of the method
Use a group of sieves to grade and sieve to determine the particle size of dispersed polytetrafluoroethylene resin. Use mechanical sac movement to grade and sieve the resin in a predetermined time.
3.2.2 Instruments and devices
Balance: Sensitivity 0.1g.
3.2.2.2 Sieve s): diameter 200mm, aperture 1440, 1000, 710, 500, 355, 250, 180μm. 3.2.2.3 Electric vibrating sieve machine
Motor power: 90W.
Motor speed: 1400r/min;
Number of sieve layers: 7 layers.
3.2.2.4 Refrigerator: household refrigerator.
3.2.2.5 Plastic bottle), 500mL.
3.2.3 Test conditions
The dew point temperature in the test room is lower than the refrigerator temperature. 3.2.4 Operation steps
3.2.4.1 Place the sample in a plastic bottle and place it in a refrigerator below 10℃ for 24h. 3.2.4.2 According to the type of resin to be tested, select matching sieves from Table 1 and weigh them respectively (accurate to 0.1g). Record the mass ml of each sieve and arrange them from top to bottom according to the order of Table 1. 3.2.4.3 Select the sample amount from Table 2 and weigh it (accurate to 0.1g). 3.2.4.4 Place the sample in the top sieve and vibrate for 10 minutes, weigh the mass of the sieves with resin left, and record the mass m2 of each sieve with resin left.
3.2.5 Expression of results and test report
The calculation method and test report are the same as those of the wet sieving method (see 3.1.5, 3.1.7). Instructions for use:
5] ASTMD1457 stipulates the American standard series of sieves, that is, the diameter is 203mm, and the apertures are 1400, 1000, 710, 500.335, 250, 180μm. 6】ASTMD1457 stipulates that it is an aluminum pan.
A1 Scope
HG/T2901—1997
Appendix A
(Standard Appendix)
65um sieve retention test method
This appendix is applicable to polytetrafluoroethylene resin with a particle size of less than 100μm. For the determination of particle size distribution, except for using only three sieves, the other methods are similar to the wet sieving method.
A2 Principle of the method
The resin is sieved with a 65μm\ sieve, and 95% ethanol 8 is sprayed during sieving to break up the material clumps and prevent the sieve holes from being blocked. A3 Reagents
95% ethanol 8.
A4 Instruments and devices
A4.1 Sieve 9)
The diameter is 200mm, and the apertures are 900, 65, and 45μm. A4.2 Balance
Sensitivity: 0.01g.
A4.3 Fume hood, sieving and spraying device
See 3.1.3.3 and 3.1.3.4.
A4.4 Stopwatch
A5 Operation steps
A5.1 Weighing
A5.1.1 Weigh the mass (m1) of the 65μm sieve on the balance (accurate to 0.01g). A5.1.2 Arrange the sieves from top to bottom in order of mesh size from large to small. A5.1.3 Weigh 10g of the sample (accurate to 0.01g) and place it in the top sieve. A5.2 Spraying
A5.2.1 Adjust the flow rate of 95% ethanol to (6±0.5)L/min. Aim at the 900μm sieve and spray for 1 minute, move the nozzle in a circular motion, carefully break up all the lumps, and rinse the resin on the side of the sieve. A5.2.2 Remove the 900μm sieve (replace the 45μm sieve with a clean sieve of the same aperture), and spray for 6 minutes on the 65um sieve.
A5.3 Drying and weighing
Dry the 65μm sieve in a fume hood for 15 minutes, then put it in an oven and dry it at 90℃ for 30 minutes1. Weigh the mass (m) of the sieve and the resin, and weigh it to 0.01g.
Instructions for use:
7) ASTMD1457 stipulates a 63um sieve.
8] ASTM D 1457 stipulates perchloroethylene, but other liquids can also be used. 9】ASTMD1457 stipulates the American standard series sieves, that is, the diameter is 203mm, and the apertures are 850, 63, and 45μm. 10］ASTMD1457 stipulates that the 63μm sieve is directly placed in an oven at 80℃～120℃ for more than 20 minutes". 920
A5.4 Filtration
HG/T 2901—1997
Filter the circulating 95% ethanol with a sieve with a mesh of 38.5μm to prevent the resin from entering the circulating liquid. Finally, put the 95% ethanol into a container for precipitation and take the clear liquid for use.
A6 Result display
A6.1 65μm sieve resin retention amount
Calculate the 65μm sieve resin retention amount m according to (A1): m=mz
65μm sieve resin retention amount, g;
Where: m-—
m2 --The mass of the 65um sieve with resin, g3ml---The mass of the 65μm sieve, g.
A6.2Retention percentage of resin on 65μm sieve
Calculate the retention percentage of resin on 65μm sieve according to formula (A2): R
Where: R—
Retention percentage of resin on 65um sieve, %,
Retention amount of resin on 65um sieve, gs
M——Mass of sample, g.
Test report
The test report should include the following contents:
a) Sample model and batch number;
b) Sampling date,
c) Retention amount of resin on 65μm sieve;
d) Retention percentage of resin on 65μm sieve; e) Test date and test personnel.335, 250, 180μm. 6】ASTMD1457 stipulates that it is an aluminum pan.
A1 Scope
HG/T2901—1997
Appendix A
(Standard Appendix)
65um sieve retention test method
This appendix is applicable to polytetrafluoroethylene resin with a particle size of less than 100μm. For the determination of particle size distribution, except for using only three sieves, the other methods are similar to the wet sieving method.
A2 Principle of the method
The resin is sieved with a 65μm\ sieve, and 95% ethanol 8 is sprayed during sieving to break up the material clumps and prevent the sieve holes from being blocked. A3 Reagent
95% ethanol 8.
A4 Instruments and devices
A4.1 Sieve 9)
Diameter: 200 mm, apertures: 900, 65, 45 μm. A4.2 Balance
Sensitivity: 0.01 g.
A4.3 Fume hood, sieving and spraying device
See 3.1.3.3 and 3.1.3.4.
A4.4 Stopwatch
A5 Operating steps
A5.1 Weighing
A5.1.1 Weigh the mass (m1) of the 65 μm sieve on the balance (accurate to 0.01 g). A5.1.2 Arrange the sieves from top to bottom in descending order according to the size of the sieve holes. A5.1.3 Weigh 10 g of the sample (accurate to 0.01 g) and place it in the top sieve. A5.2 Spraying
A5.2.1 Adjust the flow rate of 95% ethanol to (6±0.5) L/min. Spray the 900μm sieve for 1 minute, move the nozzle in a circular motion, carefully break up all the lumps, and rinse the resin on the side of the sieve. A5.2.2 Remove the 900μm sieve (and replace the 45μm sieve with a clean sieve of the same aperture), and spray the 65um sieve for 6 minutes.
A5.3 Drying and weighing
Dry the 65μm sieve in a fume hood for 15 minutes, then put it in an oven and dry it at 90℃ for 30 minutes1. Weigh the mass (m) of the sieve and the resin, and weigh it to 0.01g.
Instructions for use:
7) ASTMD1457 stipulates a 63um sieve.
8] ASTM D 1457 specifies perchloroethylene, but other liquids can also be used. 9] ASTM D1457 specifies the American standard series sieve, which is 203mm in diameter and 850, 63, and 45μm in aperture. 10］ASTMD1457 stipulates that the 63μm sieve is directly placed in an oven at 80℃～120℃ for more than 20 minutes". 920
A5.4 Filtration
HG/T 2901—1997
Filter the circulating 95% ethanol with a sieve with a mesh of 38.5μm to prevent the resin from entering the circulating liquid. Finally, place the 95% ethanol in a container for precipitation and take the clear liquid for use.
A6 Result display
A6.1 65μm sieve resin retention amount
Calculate the 65μm sieve resin retention amount m according to (A1): m=mz
65μm sieve resin retention amount, g;
Where: m-—
m2 --The mass of the 65um sieve with resin, g3ml---The mass of the 65μm sieve, g.
A6.2Retention percentage of resin on 65μm sieve
Calculate the retention percentage of resin on 65μm sieve according to formula (A2): R
Where: R—
Retention percentage of resin on 65um sieve, %,
Retention amount of resin on 65um sieve, gs
M——Mass of sample, g.
Test report
The test report should include the following contents:
a) Sample model and batch number;
b) Sampling date,
c) Retention amount of resin on 65μm sieve;
d) Retention percentage of resin on 65μm sieve; e) Test date and test personnel.335, 250, 180μm. 6】ASTMD1457 stipulates that it is an aluminum pan.
A1 Scope
HG/T2901—1997
Appendix A
(Standard Appendix)
65um sieve retention test method
This appendix is applicable to polytetrafluoroethylene resin with a particle size of less than 100μm. For the determination of particle size distribution, except for using only three sieves, the other methods are similar to the wet sieving method.
A2 Principle of the method
The resin is sieved with a 65μm\ sieve, and 95% ethanol 8 is sprayed during sieving to break up the material clumps and prevent the sieve holes from being blocked. A3 Reagent
95% ethanol 8.
A4 Instruments and devices
A4.1 Sieve 9)
Diameter: 200 mm, apertures: 900, 65, 45 μm. A4.2 Balance
Sensitivity: 0.01 g.
A4.3 Fume hood, sieving and spraying device
See 3.1.3.3 and 3.1.3.4.
A4.4 Stopwatch
A5 Operating steps
A5.1 Weighing
A5.1.1 Weigh the mass (m1) of the 65 μm sieve on the balance (accurate to 0.01 g). A5.1.2 Arrange the sieves from top to bottom in descending order according to the size of the sieve holes. A5.1.3 Weigh 10 g of the sample (accurate to 0.01 g) and place it in the top sieve. A5.2 Spraying
A5.2.1 Adjust the flow rate of 95% ethanol to (6±0.5) L/min. Spray the 900μm sieve for 1 minute, move the nozzle in a circular motion, carefully break up all the lumps, and rinse the resin on the side of the sieve. A5.2.2 Remove the 900μm sieve (and replace the 45μm sieve with a clean sieve of the same aperture), and spray the 65um sieve for 6 minutes.
A5.3 Drying and weighing
Dry the 65μm sieve in a fume hood for 15 minutes, then put it in an oven and dry it at 90℃ for 30 minutes1. Weigh the mass (m) of the sieve and the resin, and weigh it to 0.01g.
Instructions for use:
7) ASTMD1457 stipulates a 63um sieve.
8] ASTM D 1457 specifies perchloroethylene, but other liquids can also be used. 9] ASTM D1457 specifies the American standard series sieve, which is 203mm in diameter and 850, 63, and 45μm in aperture. 10］ASTMD1457 stipulates that the 63μm sieve is directly placed in an oven at 80℃～120℃ for more than 20 minutes". 920
A5.4 Filtration
HG/T 2901—1997
Filter the circulating 95% ethanol with a sieve with a mesh of 38.5μm to prevent the resin from entering the circulating liquid. Finally, place the 95% ethanol in a container for precipitation and take the clear liquid for use.
A6 Result display
A6.1 65μm sieve resin retention amount
Calculate the 65μm sieve resin retention amount m according to (A1): m=mz
65μm sieve resin retention amount, g;
Where: m-—
m2 --The mass of the 65um sieve with resin, g3ml---The mass of the 65μm sieve, g.
A6.2Retention percentage of resin on 65μm sieve
Calculate the retention percentage of resin on 65μm sieve according to formula (A2): R
Where: R—
Retention percentage of resin on 65um sieve, %,
Retention amount of resin on 65um sieve, gs
M——Mass of sample, g.
Test report
The test report should include the following contents:
a) Sample model and batch number;
b) Sampling date,
c) Retention amount of resin on 65μm sieve;
d) Retention percentage of resin on 65μm sieve; e) Test date and test personnel.
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