Simple identification method of cellulose ether for putty mortar

Cellulose ether is a commonly used building material additive, widely used in putty mortar. In order to ensure the quality and performance of putty mortar, it is very important to quickly and accurately identify the type and quality of cellulose ether.

1. Appearance identification method

Color observation: High-quality cellulose ether is usually white or light yellow. If the cellulose ether is dark yellow or has other colors, it may indicate that its purity is not high or there are impurities.

Particle condition: High-quality cellulose ether should be a fine and uniform powder without obvious granular substances. If more particles are found, it may be a manifestation of poor quality.

2. Solubility test

Water solubility: Take a small amount of cellulose ether (about 1 gram), put it in 100 ml of water, and stir evenly. High-quality cellulose ether should be able to dissolve quickly and evenly, and there should be no obvious agglomeration or precipitation.

Viscosity test: The quality of cellulose ether solution can be preliminarily judged by testing its viscosity. High-quality cellulose ether solution should have a high and stable viscosity, and should not have a low viscosity or unstable viscosity.

3. Heating test

Thermal stability: Take an appropriate amount of cellulose ether and put it into a test tube, and observe its changes during the heating process. High-quality cellulose ether will not change color or decompose when heated to 150°C. If there is obvious color change or decomposition, it means that its thermal stability is poor.

4. Chemical reaction test

Acid-base test: Take a small amount of cellulose ether and dissolve it in an acidic solution (such as dilute hydrochloric acid) and an alkaline solution (such as dilute sodium hydroxide) respectively, and observe its dissolution. High-quality cellulose ether should be able to maintain good stability in an acid-base environment, and there should be no obvious solubility change or precipitation.

Salting out experiment: Take a certain amount of cellulose ether solution and add saturated sodium chloride solution. High-quality cellulose ether should be completely dissolved and there should be no obvious precipitation.

5. Sensory test

Touch test: Gently twist the cellulose ether powder with your fingers. High-quality cellulose ether should feel smooth and delicate, and should not have obvious granularity or roughness.

Odor test: High-quality products made by professsional cellulose ether manufacturer should have no odor or only a slight characteristic odor. If you smell a clear pungent odor, it may indicate that it has impurities or quality problems.

6. Instrumental detection method

Infrared spectroscopy analysis (FTIR): The chemical structure and composition of cellulose ether can be determined by infrared spectroscopy analysis. High-quality cellulose ether should have specific infrared absorption peaks.

Thermogravimetric analysis (TGA): The mass change of cellulose ether at different temperatures can be understood by thermogravimetric analysis. High-quality cellulose ether should have a higher thermal decomposition temperature and a lower residue content.

Scanning electron microscope (SEM): The microstructure and morphology of cellulose ether can be observed by scanning electron microscope. High-quality cellulose ether should have a uniform and dense microstructure.

7. Practical application test

Performance test: Add cellulose ether to putty mortar in a certain proportion, and make samples for actual performance testing. Including but not limited to: construction performance, water retention, crack resistance and strength. High-quality cellulose ether should be able to significantly improve the various properties of putty mortar.

Weather resistance test: Expose the putty mortar sample with cellulose ether added to different environmental conditions, such as high temperature, high humidity, ultraviolet irradiation, etc., and observe its performance changes. High-quality cellulose ether should be able to effectively improve the weather resistance of putty mortar.

The above simple identification method can be used to preliminarily judge the quality and performance of cellulose ether and provide a reference for practical application. Of course, the most accurate identification results still require detailed analysis with the help of professional laboratory testing methods.