This standard specifies the technical requirements, test methods, inspection rules and marking, packaging, storage and transportation of organic bentonite for coatings. This standard applies to organic bentonite for coatings. The organic bentonite is made from sodium-based or calcium-based (or sodium-based and calcium-based mixed) bentonite by crushing, purification, modification and organic activation. It can be used in paints and primers to prevent pigments and body pigments from producing hard precipitation, and has the function of thickening and preventing paint from sagging. HG/T 2248-1991 Organic bentonite for coatings HG/T2248-1991 Standard download decompression password: www.bzxz.net

Chemical Industry Standard of the People's Republic of China
HG/T2248—91
Organobentonite for Coatings
Published on November 12, 1991
Ministry of Chemical Industry of the People's Republic of China
Implemented on July 1, 1992
Chemical Industry Standard of the People's Republic of China
Organobentonite for Coatings 10
1 Subject Content and Scope of Application
HG/T2248—91
This standard specifies the technical requirements, test methods, inspection rules and marking, packaging, storage and transportation of organic bentonite for coatings. This standard applies to organic bentonite for coatings. The organic bentonite is made from sodium-based (or calcium-based or sodium-based and calcium-based mixed) bentonite through crushing, purification, deformation and organic activation treatment. It can be used in paints and primers to prevent pigments and body pigments from producing hard precipitation, and has the function of thickening and preventing paint from sagging. Cited standards
Determination of pigment sieve residue
GB1715
Determination of volatile matter of pigment at 105C
3 Test sieve
GB6003
GB6682
Specification of laboratory water
GB9285
3 Product classification
Sampling of raw materials for paints and varnishes
According to the applicable scope of organic bentonite for coatings, it can be divided into the following two categories: Category I is suitable for low to medium polar coatings containing solvents such as xylene Category I is suitable for low polar coatings containing solvents such as No. 200 paint solvent oil 4 Technical requirements
The product should meet the technical requirements listed in the following table. Item
Viscosity, Pas
Volatile matter at 105℃, %
Fineness (through 76um sieve), %
Loss on ignition, %
5Test method
Not less than
Not more than
Not less than
Not more than
Off-white powder
Unless otherwise specified, analytically pure reagents and grade 3 water in accordance with GB6682 shall be used in the test. The following tests are all parallel determinations of duplicate samples. 5.1 Appearance determination
Approved by the Ministry of Chemical Industry of the People's Republic of China on November 12, 1991
Light yellow or off-white powder
Implementation on July 1, 1992
Determined by visual method
5.2 Viscosity determination
5.2.1 Reagents
5.2.1.1 Xylene.
5.2.1.2 200 paint solvent oil: industrial product. HG/T2248-91
5.2.1.3 95% methanol (mm) is prepared by adding appropriate amount of water to 99.5% methanol. 5.2.2 Instruments
5.2.2.1 High-speed mixer.
Note: GFJ-0.4A high-speed mixer is applicable, and its speed range is 0-8000r/min, which can be adjusted manually. 5.2.2.2 Container: A porcelain cylinder with an inner diameter of about 60 mm and a height of about 120 mm or a similar round container made of other non-breakable materials (stainless steel, polytetrafluoroethylene, etc.). This container can be adapted to the paddle of a high-speed mixer with a diameter of about 45 mm. 5.2.2.3 Rotational viscometer.
Note: ND-J79 type rotational viscometer is applicable. 5.2.2.4 Balance, with a sensitivity of 0.2 mg.
5.2.2.5 Stopwatch: with a graduation of 0.2 s.
5.2.3 Determination steps
Accurately weigh 3.60 g of the sample into a clean and dry container (5.2.2.2), add 54 mL of xylene (Class 1) or No. 200 paint solvent oil (Class 1), and place the container under the high-speed mixer so that the paddle is immersed below 1/3 of the liquid. Turn on the power supply, gradually adjust the speed to 2100~2300r/min, and stir at this speed for 5 minutes. After stopping the rotation, add 1.5mL of methanol. Make the leaves immerse 2/3 below the liquid surface, slowly adjust the speed to 3400~3600r/min, and stir at this speed for 5 minutes. During the last 2 minutes of stirring, you should move the container slightly up and down and left and right by hand to stir it evenly. After stopping the rotation, remove the container and immediately use a scraper to load the gel into a suitable viscosity tester (such as the second unit viscosity tester when using the NDJ-79 viscometer), vibrate the tester while loading to fill it and drive away the bubbles, and use a scraper to scrape it flat along the upper edge of the tester. Then put in the rotor and place the tester with the rotor under the viscometer. After adjusting the viscometer to zero, hang the rotor on the rotating hook, turn on the power supply for measurement, and record the reading value when the pointer is initially stable (about 5 to 15 seconds). If the pointer is still unstable within 15 seconds, record the highest and lowest values, and take the average value as the reading value. The reading value multiplied by the rotor factor (when the NDJ-79 viscometer uses the second unit viscosity tester and the No. 3 rotor (shear rate is 176s-1), the rotor factor is 0.1) is the viscosity value (Pa·s). During the measurement, the temperature is maintained at 23±1°C.
The average value of the two average measurements is taken as the result. The difference between the two measured values ​​should not be greater than 15% of the larger value, otherwise the measurement should be repeated. 5.3105°C volatile matter determination
Perform according to GB5211.3. www.bzxz.net
5.4 Fineness determination
According to the provisions of GB1715 B method, the test sieve should comply with the provisions of GB6003, the aperture is 76um, and the fineness X (%) is calculated according to formula (1): ml-m2×100
Where: m1——sample mass, 8;
m2—screen residue mass g;
Take the average of two parallel determinations as the result. The difference between the two determinations should not be greater than 2% of the larger value, otherwise the determination should be repeated. 5.5 Determination of loss on ignition
5.5.1 Instrument
5.5.1.1 High temperature furnace: capable of controlling the temperature within the range of 850~900℃. 5.5.1.2 The sensitivity of the balance is 0.2mg.
5.5.2 Determination steps
Place a clean crucible in a high-temperature furnace at a temperature of 850~900℃ and burn it to constant weight (the difference between two consecutive weighings is not greater than 0.5mg). 2
HG/T2248-—91
Weigh about 2g of the sample (accurate to 0.2mg) in a constant weight crucible, place it in a 300℃ high-temperature furnace, slowly heat it to 850~900℃ and burn it to constant weight, take out the crucible and place it in a desiccator to cool to room temperature, and weigh it. 5.5.3 Expression of results
Ignition loss X2 (%) is calculated according to formula (2):
X2-ml=m2×100
Where: m1——mass of sample added to the crucible, g; m2——mass of residue added to the crucible after ignition, g: m3——mass of added crucible, g.
（2）
Take the average of two parallel measurements as the result (round to one decimal place). The difference between the two measured values ​​should not be greater than 2% of the larger value, otherwise the measurement should be repeated.
6 Acceptance Rules
6.1 All technical requirements listed in this standard are type inspection items, among which appearance, viscosity, volatile matter at 105℃ and fineness are listed as factory inspection items. Under normal production conditions, type inspection is carried out once a quarter. 6.2 Products are inspected by the inspection department of the manufacturer in accordance with the provisions of this standard. The manufacturer shall ensure that all products leaving the factory meet the technical requirements of this standard. The product shall have a certificate of conformity and, if necessary, instructions for use and precautions. 6.3 The receiving department has the right to accept the product in accordance with the provisions of this standard. If it is found that the quality does not meet the technical requirements of this standard, the supply and demand parties shall jointly re-sample and re-test in accordance with GB9285. If it still does not meet the technical requirements of this standard, the product is unqualified and the receiving department has the right to return it.
6.4 The product shall be sampled in accordance with the provisions of GB9285. After the sample is mixed, it shall be shrunk to about 200g and packed into two clean and dry brown wide-mouth bottles with stoppers. Labels shall be affixed to the bottles, indicating: manufacturer name, batch number, sampling date, sampler and sample name. One bottle shall be sent to the inspection department for inspection, and the other bottle shall be sealed with paraffin and stored for future reference.
6.5 Both the supplier and the buyer shall inspect and verify the product packaging, quantity and markings. If the packaging is damaged or leaking, the quantity is inconsistent, or the markings do not meet the requirements, the relevant departments shall be notified in time for handling. 6.6 When disputes arise between the supplier and the buyer over product quality, arbitration inspection shall be conducted by the product quality supervision and inspection agency. 6.7 The inspection results shall be determined by the rounded value comparison method. 7 Packaging, marking, purchase, storage and transportation
7.1 The product is packed in a plastic woven bag lined with plastic film (it is best to have a double layer of kraft paper bag between the plastic bag and the woven bag), the plastic bag mouth is tied tightly with a plastic belt, and the woven bag mouth is sealed with a bag sewing machine. The net weight of each bag is 20kg or 25kg. 7.2 The woven bag should be printed with obvious and firm marks, indicating the product name, trademark, batch number, net weight, gross weight, manufacturer name and production date, etc.
7.3 The product should be stored in a dry and ventilated place and avoid direct sunlight and heat. 7.4 The product should be loaded and unloaded gently during transportation to prevent damage to the packaging and rain, and comply with the relevant regulations of the transportation department. 7.5 The product has an effective storage period of one year from the date of production under the prescribed packaging, storage and transportation conditions. After the storage period, it can be inspected according to the items specified in this standard. If the results meet the requirements, it can still be used. Additional notes:
This standard was proposed by the Science and Technology Department of the Ministry of Chemical Industry of the People's Republic of China. This standard is under the jurisdiction of the National Technical Committee on Standardization of Paints and Pigments. This standard was drafted by the Paint Industry Research Institute of the Ministry of Chemical Industry and Lin'an Chemical Plant of Zhejiang Province. The main drafters of this standard: Wu Liangjun, Xiang Guantao, and Ye Jianchun. 3
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