Original Article:
High Temperature Sensing and Detection for Cementitious Materials Using Manganese Violet Pigment
Rajagopalan Sam Rajadurai et al.
Materials. 2020, 13(4), 993
10.3390/ma13040993
This study investigated the thermochromic properties of inorganic manganese violet (MV) with increasing temperature, including reversible and irreversible color change properties, and further investigated its application potential in high-temperature sensing and detection of cementitious materials. Manganese violet pigment is composed of manganese dioxide, ammonium dihydrogen phosphate and phosphoric acid, and has a dark violet color due to the presence of phosphate and ammonia. Between room temperature and 370°C, the color of the pigment reversibly changes from violet to blue due to the expulsion of water from the pigment particles. The violet starts to fade above 370 °C, but not enough to be precisely observed. At temperatures above 400 °C, the color of the pigment irreversibly changes from violet to grayish yellow due to the evaporation of water and the release of ammonia from the pigment particles. MV pigments were mixed with white cement in different proportions, and the RGB and Lab values of the mixed samples were determined at different temperatures, which are promising for identifying the magnitude and dispersion of critical temperatures in cementitious materials and structures using MV pigments. This identification strategy of color changes provides a new idea for the assessment of high temperature damaged structures.
Chemicals Related in the Paper:
| Catalog Number | Product Name | Structure | CAS Number | Price |
|---|---|---|---|---|
| ACM10101663 | Manganese violet |  |
10101-66-3 | Price |
