8878
We show that the plastic deformation is governed by yielding in the polystyrene sublayer , which renders the overall system soft for plastic deformation .
 Chemical: polystyrene
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: polystyrene 
Answer:
 Chemical: polystyrene