13mm no need to demold infrared compression mold

13mm no need to demold infrared compression moldUsage tips:

The temperature in the laboratory should be between 15-30 ℃, the relative humidity should be below 65%, and the power supply used should be equipped with a voltage regulator and grounding wire. Due to strict control of indoor relative humidity, the area of the infrared laboratory should not be too large to accommodate necessary instruments and equipment, but there must be a dehumidification device indoors.

To prevent the instrument from being affected by moisture and affecting its service life, the infrared laboratory should be kept dry regularly. Even if the instrument is not in use, it should be turned on at least twice a week for half a day each time, and the dehumidifier should be turned off for dehumidification. Especially during the rainy season, the dehumidifier can be shut down every day.

03. If a single beam Fourier transform infrared spectrophotometer (currently widely used) is used, the CO2 content in the laboratory should not be too high. Therefore, the number of people in the laboratory should be minimized, and unrelated personnel should not enter. Proper ventilation should also be taken into account.

The commonly used sample preparation method for infrared spectroscopy is the (KBr) pellet method. Therefore, in order to reduce the impact on the measurement, the KBr used should be of optical reagent grade or at least analytical grade. Before use, it should be finely ground (below 200 mesh) and dried at 120 ℃ for more than 4 hours before being stored in a dryer for later use. If lumps are found, they should be dried again. The prepared empty KBr sheet should be transparent, with a light transmittance of at least 75% compared to air.

05. If the test substance is hydrochloride salt, considering the possible ion exchange phenomenon during the tablet pressing process, the standard stipulates that Kcl (also used after pretreatment like KBr) should be used instead of KBr for tablet pressing. However, the spectra measured after Kcl tablet pressing and KBr tablet pressing can also be compared. If there is no difference between the two, KBr can be used for tablet pressing.

The amount of test sample used in the tablet pressing method is generally 1-2mg. As it is not possible to weigh it with a balance and add it, and the absorption degree of infrared light varies for each sample, it is often taken based on experience. Generally, it is required that the majority of absorption peaks in the obtained spectrum are within the range of 10% to 80% transmittance. If the transmittance of the strong absorption peak is too high (such as greater than 30%), it indicates that the sampling amount is too small; On the contrary, if the strong absorption peak is close to a transmittance of 0% and is a flat peak, it indicates that the sampling amount is too large. In this case, the sampling amount should be adjusted and re measured.

07. The amount of KBr used for tablet pressing is generally around 200mg. The amount of KBr should be controlled according to the thickness of the tablet after production. Generally, the thickness of the tablet should be below 0.5mm. When the thickness is greater than 0.5mm, interference fringes can often be observed in the spectrum, which can interfere with the spectrum of the test sample.

When pressing tablets, the test sample should be taken and finely ground before adding KBr to grind it again, which makes it easier to mix. The agate mortar should be used for grinding, as the inner surface of the glass mortar is relatively rough and easy to adhere to the sample. When grinding, uniform force should be applied in the same direction (clockwise or counterclockwise). If the grinding is not done in the same direction, it may cause the test sample to undergo crystal transformation during the grinding process, thereby affecting the measurement results. The grinding force does not need to be too strong, as there are no visible small particles in the sample after grinding. After the sample is well prepared, it should be poured into the tablet mold through a small funnel and spread evenly as much as possible. Otherwise, the transparency of the areas with fewer samples after tablet pressing will be lower than that of the areas with more samples, which will affect the measurement. In addition, if opaque white spots appear on the pressed sample, it indicates that there are small particles that have not been finely ground in the sample and should be re pressed.

09. The sample used for measurement should be dried, otherwise it should be dried for a few minutes under an infrared lamp after grinding. After the sample is prepared and installed in the mold, it should be connected to a vacuum pump and vacuumed for at least 2 minutes to further remove the moisture in the sample. Then, it should be pressurized to 0.8-1GPa (8-10T/cm2) and maintained for 2-5 minutes. Not vacuuming will affect the transparency of the film.

10. After using the compression mold, all parts should be wiped clean immediately, and if necessary, wiped clean with anhydrous ethanol cotton balls and stored in a dryer to prevent contamination and corrosion.

13mm no need to demold infrared compression moldProduct Parameters: