15505
This is achieved by a detailed investigation of a wide range of polystyrene - poly ( 4 - vinyl pyridine ) ( PS - P4VP ) block copolymers , in contrast to much more limited ranges in previous studies .
 Chemical: polystyrene - poly ( 4 - vinyl pyridine ); Chemical: PS - P4VP
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 - poly ( 4 - vinyl pyridine ), PS - P4VP 
Answer:
 Chemical: polystyrene - poly ( 4 - vinyl pyridine ); Chemical: PS - P4VP