Pelapis dan pernis merupakan bahan yang sangat diperlukan dalam berbagai aplikasi, and their density is one of the important parameters to evaluate their quality and performance. This article will explain how to measure the density of paints and varnishes using a pycnometer, including the scope of application, the required instruments and materials, and detailed measurement steps.

1. Ruang lingkup dan deskripsi

Density refers to the mass per unit volume of liquid at a specified temperature, usually expressed in g/ml. This method is suitable for determining the density of liquid coatings, varnishes and other products at specified temperatures. The principle is to use the density of distilled water to calibrate the volume of the specific gravity bottle, and then weigh the mass of the sample through the specific gravity bottle at a certain temperature, so as to calculate the density of the sample.

2. Instrumen dan bahan

Specific gravity bottles: usually available in different capacities, such as 37ml, 50ml and 100ml, made of stainless steel or aluminum alloy.

Termometer: Accuracy to 0.2 °C, biasanya 0.1 °C.

Constant temperature water bath or constant greenhouse: it is required to be able to maintain within ±0.5 ° C of the test temperature, or higher accuracy is required to be within the range of ±0.2 ° C.

Analytical balance: Accuracy to 0.2mg.

Cara mengukur massa jenis cat pernis dengan berat jenis botol

3. Metode penentuan

Calibration of pycnometer:

Use a clean, dry pycnometer and weigh it at room temperature.

The bottle is cleaned, dried and weighed continuously until the difference between the two successive weights does not exceed 0.5mg.

At the test temperature (usually 23±2 ° C, or 23±0.5 ° C for higher accuracy), fill the pyretic flask with distilled water to ensure that there are no bubbles.

Place the pycnometer in a constant temperature water bath or a constant greenhouse until the temperature is constant. During this process, make sure that there are no residual water droplets on the outside of the pycnometer.

Immediately weigh a pyretic flask filled with distilled water, akurat untuk 0.001%.

Cara mengukur massa jenis cat pernis dengan berat jenis botol

Calculation of the volume of the specific gravity bottle:

Use the following formula to calculate the volume of the pycnometer (expressed in ml) :

V = (m1 – m0)/V

Diantara mereka:

V is the volume (ml) of the pycnometer.

m1 is the mass (G) of a pycnometer filled with distilled water.

m0 is the mass (G) of the dry specific gravity bottle.

p is the density of distilled water (biasanya 1 g/ml).

Cara mengukur massa jenis cat pernis dengan berat jenis botol

Measurement of product density:

Repeat the procedure with the sample instead of the distilled water.

Selama operasi, wear analytical gloves to avoid direct contact with the pycnometer.

Perhatian harus diberikan untuk menghindari gelembung ketika menyuntikkan sampel ke dalam botol piretik dan untuk memastikan bahwa bagian luar botol piretik bersih untuk memastikan penimbangan yang akurat..

4. Presentasi hasil

Hitung massa jenis produk pada suhu uji T (biasanya 23 ° C atau suhu lain yang disepakati), dinyatakan dalam g/ml, sesuai dengan rumus berikut:

Massa jenis = massa sampel/volume sampel

Cara mengukur massa jenis cat pernis dengan berat jenis botol

5. Kesimpulan

Mengukur kepadatan cat dan pernis merupakan langkah penting dalam memastikan kualitas dan kinerjanya. Dengan menggunakan botol berat jenis dan instrumen yang sesuai, kepadatan produk dapat diukur secara akurat, sehingga membantu produsen dan pengguna untuk menilai kesesuaian dan kualitasnya. Data kepadatan sangat penting untuk pengendalian produksi dan pengendalian kualitas, jadi metode pengukuran dan pemilihan instrumen yang benar sangatlah penting. Melalui pengukuran kepadatan, sifat fisik cat dan pernis dapat lebih dipahami untuk mendukung pengaplikasiannya.