23827
The membranes could be easily detached from polystyrene or polypropylene substrate without any postprocessing step .
 Chemical: polystyrene; Chemical: polypropylene
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: polystyrene; Chemical: polypropylene