15297
The rate of ring - opening of the spiropyran - polymer brushes coatings has been determined in situ in the presence of different solvents , showing that the coloration rate is also influenced by the solvent polarity and therefore can be used as an additional parameter for solvent sensing .
 spiropyran
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 spiropyran